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Ofer Reany, Associate Professor

Contact Info

The Open University of Israel Department of Natural Sciences 1 University Road P.O.B. 808 Ra’anana 43107, Israel
Office:+972-9-7780980 Fax:+972-9-7780980 Email:oferre@openu.ac.il

Additional Information

 Prof. Ofer Reany, Dean of Research

 

 Available vacancy:

 Research description:  

We are seeking a highly motivated postdoctoral scholar to join our research team, that are interested to be involved in the field of supramolecular and polymer chemistries, catalysis and advanced chemical transformations.

Fellowship:
 Candidates will be offered a competitive funding commensurate with their experience.
 
To apply:
 Individuals interested in applying should send their curriculum vitae (CV), a description of their research experience, a statement of research interests, and a list of three references via email to: oferre@openu.ac.il

 

 

 

Ofer Reany, an Associate Professor of Chemistry, shares his research activities between two hosting academic institutions in collaboration with Prof. E. Keinan (Technion) and collaboration with Prof. N. G. Lemcoff (Ben-Gurion University of the Negev).
At the Technion, his studies are focused on Supramolecular Chemistry – the chemistry beyond the molecules. In this field, his research interests are focused on developing macrocyclic cavitands, their host-guest chemistry, and their applications in the design of artificial machines, switches, and cargo delivery devices.
His research at Ben-Gurion University focuses on developing new chemical transformation methodologies, organocatalysis, and photochemistry in olefin metathesis. Also, his research interests are focused on studying thermomechanical properties of polymers derived from either [3]catenane-based monomers or dicyclopentadiene (DCPD) derivatives for ring-opening metathesis polymerization (ROMP). Poly[3]catenane chains are expected to exhibit a high degree of mobility, highlighting their potential applications in polymeric devices where enhanced elasticity or thermal relaxation are required. In contrast, DCPD-based polymers enjoy high impact strength, high chemical corrosion resistance and offer control over thermomechanical properties of the resulting crosslinked polymers, depending on initiator type and loading, the curing method, and the monomer's chemical structure.

In October 2020, Prof. Ofer Reany was appointed Dean of Research

 Short Resume

Ofer Reany was born in Tel-Aviv in 1967. He finished his undergraduate studies at Tel-Aviv University, where he also received his Ph.D. degree in chemistry in 1998 on studies of novel aminal supramolecular systems under Prof. Benzion Fuchs' supervision. He then worked with Prof. David Parker in the Chemistry Department of Durham University (UK) on chemical sensors for diagnostic applications. At the end of 2000, he joined the Research and Development Division of Israel Chemicals Ltd., and in 2002 he became the head of the Analytical Division at Aromor Ltd.
In 2006 he joined Prof. Ehud Keinan's group at the Technion as a senior researcher and lab manager, and in 2011 he moved to the Open University of Israel, where he is currently an Associate Professor at the Natural Sciences Department.

 

1998
Ph.D. in Chemistry, Tel-Aviv University
1993
M.Sc. (Cum Laude) in Chemistry, Tel-Aviv University
1991
B.Sc. in Chemistry, Tel-Aviv University
2018 -
Research Visitor at Prof. Hagen Bayley Research Group, Department of Chemistry, Oxford University, UK
2017 -
Associate Professor, Natural Sciences Department, The Open University of Israel
2015 -
Guest Researcher in the Chemistry Department at the Ben-Gurion University of the Negev
2013 - 2017
Senior Lecturer, Natural Sciences Department, The Open University of Israel
2013 - 2019
Guest Researcher in the Chemistry Faculty at the Technion
2011 - 2013
Guest Lecturer, Natural Sciences Department, The Open University of Israel
2000
EPSRC postdoctoral fellowship - A funding agency of the Engineering & Physical Sciences Research Council, University of Durham, UK
1999
BBSRC postdoctoral fellowship – A governmental funding agency part of UK Research and Innovation, University of Durham, UK
1998
David and Lina Trotzky Scholarship, Tel-Aviv University
1996
The Chemist's Federation scholarship, Tel-Aviv University

 

2020 –                       Dean of Research
2020 –                       Chair, Steering Committee of Research
2020 –                       Chair, Research Institutes Committee
2020 –                       Chair, Standard Grants Committee
2020 –                       Chair, Institutional Committee for the Use and Care of Animal Shelters
2019 –                       Chair, Ad-hock committee of academic promotion from Senior Lecturer to Associate Professor.
2014 –                       Member of the Open University Senate
2014 – 2020             Chair, Natural Sciences Academic Subcommittee

 

 

H-index: 15, total number of citations of all articles: 878, total number of citations without self-citations – 808 (Web of Science/November 2020).

 

Codes:
PI: Principal Investigator; S: Student; PD: Post-doc; C: Co-researcher; T: Technician or Laboratory assistant; *: Corresponding author.
 
40. Phatake S. R.PD, Vidavsky Y.C, Lemcoff N. G.PI and Reany O.PI,* Oil additives demonstrate dual effects on thermal and mechanical properties of cross-linked hydroxy-DCPD thermosets.
European Polymer Journal, 2021, online: DOI: https://doi.org/10.1016/j.eurpolymj.2021.110364
 
39. Solel, E.*,PD Pappo, D.C, Reany, O.C, Mejuch, T.S, Gershoni-Poranne, R.S, Botoshansky, M.T, Stanger, A.PI, and Keinan E.PI,* Flat corannulene: when a transition state becomes a stable molecule. Chemical  Science 2020, 11, 13015-13025.  https://doi.org/10.1039/D0SC04566G
 
38. Mohite A. R.PD, Phatake, R.PD, Dubey P., Agbaria M.S, Shames I. A.T, Lemcoff, N. G.PI,*and Reany, O.PI,* Thiourea-mediated halogenation of alcohols. Journal of Organic Chemistry, 2020, 85, 12901-12911. http://dx.doi.org/10.1021/acs.joc.0c01431
 
37. Mohite A. R.PD and Reany, O.PI,* Inherently chiral Bambus[4]urils. Journal of Organic Chemistry 2020, 85, 9190-9200.https://doi.org/10.1021/acs.joc.0c01174
 
36. Phatake S. R.PD, Masarwa A.T, Lemcoff N. G.PI and Reany O.PI,* Tuning thermal properties of cross-linked dcpd polymers by functionalization, initiator type and curing methods. Polymer Chemistry, 2020, 11, 1742-1751.https://doi.org/10.1039/C9PY01178A
 
35. Kunturu, P. P. Kap O. Sotthewes, K. Cazade, P. Zandvlient, H. J. W.PI,*, Thompson, D.PI,*, Reany, O.PI,* and Huskens, J.PI,* Anchoring and packing of self-assembled monolayers of semithio-Bambusurils on Au(111). Molecular Systems Design and. Engineering, 2020, 5, 511-520. https://doi.org/10.1039/C9ME00149B
 
34. Mondal P.PD, Solel E.PD Mitra S.PD, Keinan E.PI* and Reany O.PI,* Equatorial sulfur atoms in Bambusurils spawn cavity collapse. Organic Letters, 2020, 22, 204-208.
 
33. Mondal P.,PS Solel, E.,PD Fridman, N.,T Keinan E. PI.* and Reany, O. PI,* "Intramolecular vdW interactions challenge anion binding in perthio-Bambusurils" Chemistry - A European Journal 2019, 25, 13336-13343. Cover feature: Chemistry - A European Journal 2019-25/58. https://doi.org/10.1002/chem.201901822
 
32. Swamy P. C. A.PD, Solel, E.PD, Reany, O.PI,*, Keinan, E. PI,* Synthetic evolution of the multifarene cavity from planar predecessors. Chemistry – A European Journal, 2018, 24, 15319-15328. https://doi.org/10.1002/chem.201803189
 
31. Sutar, R. L.PD, Danielle, B.S, Lemcoff, N. G.PI, Reany, O.PI,* New latent metathesis catalysts equipped with exchangeable boronic ester groups on the NHC. Journal of Coordination Chemistry 2018, 71, 1715-1727. (Invited article on the occasion of Prof. Dan Meyerstein’s 80th birthday). https://doi.org/10.1080/00958972.2018.1481211.
 
30. Pinhasi van-Oss, R.S, Gopher, A.PI, Kerem, Z.C, Peleg, Z, Lev-Yadun, S., Sherman, A., Zhang, H.B.PD, Vandemark,PD G., Coyne, G, C. J.PD, Reany, O.C, Abbo. S.PI* Independent selection for seed free tryptophan content and vernalization response in chickpea domestication. Plant Breeding, 2018, 137, 290–300. https://doi.org/10.1111/pbr.12598.
 
29. Reany, O.,PI,* Sindelar, V.,PI,* Urbach, A. R.PI,* Special Issue: Cucurbiturils and related cavitands. Israel Journal of Chemistry, 2018, 58, 187.
 
28. Reany, O.,PI,* Mohite, A.PD, Keinan E.PI,*; hetero-Bambusurils. Israel Journal of Chemistry, 2018, 58, 449-460. https://doi.org/10.1002/ijch.201700138.
 
27. Sutar, R. L.PD, Sen, S.PD, Eivgi, O.S, Segalovich, G.S, Schapiro, I.PI, Reany, O.PI, Lemcoff, N. G.PI,*; Guiding a divergent reaction by photochemical control: Bichromatic selective access to levulinates and butenolides. Chemical Science, 2018, 9, 1368 – 1374. https://doi.org/10.1039/C7SC05094A.
 
26. Lang, C.C, Mohite, A.PD, Deng, X.S, Dong, Z.S, Xu, J.S, Liu, J.,PI,* Keinan, E.,PI,* Reany, O.PI,*; semithio-Bambus[6]uril is a transmembrane anion transporter. Chemical Communication, 2017, 53, 7557-7560. https://doi.org/10.1039/C7CC04026A
 
25. Reany, O.,PI,* Li, A.S, Yefet, M.S, Gilson, M. K.PI,*, Keinan, E.PI,*; Attractive interactions between heteroallenes and the cucurbituril portal. Journal of the American Chemical Society, 2017, 139, 8138-8145. https://doi.org/10.1021/jacs.6b13005
 
24. Eivgi O.S, Sutar, R. L.PD, Reany, O.PI, Lemcoff, N. G.PI,*; Bichromatic photosynthesis of coumarins by uv filter enabled olefin metathesis. Advanced Synthesis and Catalysis, 2017, 359, 2352-2357. https://doi.org/10.1002/adsc.201700316
 
23. Reany, O.,PI,* Lemcoff, N. G.PI; Light guided chemoselective olefin metathesis reactions. Pure and Applied Chemistry, 2017, 89(6), 829-840.
 
22. Singh, M.PD, Solel, E.S, Keinan, E.PI,*; Reany, O.PI,*; Aza-Bambusurils en route to anion transporters. Chem.-Eur. J., 2016, 22, 8848-8854. Cover picture: Chemistry - A European Journal, 2016-22/26, June 20th. https://doi.org/10.1002/chem.201600343
 
21. Solel, E.S, Singh M.PD, Reany, O.,PI,* Keinan, E.PI,*; Heteroatom replacement in Bambusurils creates stronger anion binders. Physical Chemistry Chemical Physics (PCCP), 2016, 18, 1318013185. Cover picture PCCP, 2016-18/19, May 21st.
 
20 Sutar, R. L.PD, Levin, E.S, Butilkov, D.S, Goldberg, I.C, Reany, O.PI, Lemcoff, N. G.PI,* A light activated olefin metathesis catalyst equipped with a chromatic orthogonal self-destruct function. Angewandte Chemie International Edition, 2016, 55, 764-767.
 
19. Bibi, H.C, Reany, O.PI, Waisman, D.T, Keinan, E.PI,*; Prophylactic treatment of asthma by an ozone scavenger in a mouse model. Bioorganic and. Medicinal Chemistry Letters, 2015, 25, 342-346. https://doi.org/10.1016/j.bmcl.2014.11.035
 
18. Singh, M.PD, Solel, E.S, Keinan, E.,PI,* Reany, O.PI,*; Dual-functional semithio-bambusurils. Chemistry - A European Journal, 2015, 21, 536-540.
 
17. Singh, M.PD, Parvari, G.S, Botoshansky, M.T, Keinan, E.,PI,* Reany, O.PI,*; The synthetic challenge of thioglycolurils. European Journal of Organic Chemistry, 2014, 5, 933-940. Cover picture: European Journal of Organic Chemistry, 5/2014, 2nd February.
 
16. Bulatov, V.C, Reany, O.PI,*, Grinko, R.T, Schechter, I.C, Keinan, E.PI,*; Time-resolved, laser initiated detonation of TATP supports previously predicted non-redox mechanism. Physical Chemistry Chemical Physics (PCCP), 2013, 15, 6041-6048. https://doi.org/10.1039/C3CP44662J
 
15. Reany, O.PI,*, Fuchs, B.PI; Lateral cis-1,3,5,7-tetraazadecalin podands and their complexes: synthesis, structure, and strong binding with Pb(II) and other heavy metal ions. Inorganic Chemistry, 2013, 52, 1976-1990. https://doi.org/10.1021/ic3023166
 
14. Sinha, M. K.C, Reany, O.PI,* Yefet, M.S, Botoshansky, M.T, Keinan, E.PI,* Bistable cucurbituril rotaxanes without stoppers. Chemistry - A European Journal, 2012, 18, 5589-5605. https://doi.org/10.1002/chem.201103434
 
13. Botoshanski, M.T, Reany, O.C, Keinan, E.PI; Crystal structures of novel CB[6] complexes with p-xylylenediammine derivatives. Acta Crystallographica A - Foundation and Advances, 2011, 67, C612-C613. https://doi.org/10.1107/S0108767311084522
 
12. Parvari, G.S, Reany, O.C, Keinan, E.PI Applicable properties of cucurbiturils. Israel Journal of Chemistry, 2011, 51, 646-663. https://doi.org/10.1002/ijch.201100048
 
11. Sinha, M. K.S, Reany, O.C, Parvari, G.S, Karmakar, A.PD, Keinan, E.PI; Switchable cucurbituril-bipyridine beacons. Chemistry - A European Journal, 2010, 16, 9056-9067. https://doi.org/10.1002/chem.200903067https://doi.org/10.1021/cg900390y
 
10. Reany, O.C, Kapon, M.T, Botoshansky, M.T, Keinan, E.PI; Rich polymorphism in triacetone triperoxide. Crystal Growth and Design, 2009, 9, 3661-3670.
 
9. Ratner, T.S, Reany, O.C, Keinan, E.PI; Encoding and processing of alphanumeric information by chemical mixtures. ChemPhysChem, 2009, 10, 3303-3309. https://doi.org/10.1002/cphc.200900520
 
8. Pappo, D.PD, Mejuch, T.C, Reany, O.C, Solel, O.C, Mahender, G.PD, Keinan, E.PI; Diverse functionalization of corannulene: easy access to pentagonal superstructures. Organic Letters, 2009, 11, 1063-1065. https://doi.org/10.1021/ol8028127
 
7. Low, M. P.PD, Parker, D.PI, Reany, O.PD, Aime, S.PI, Botta M.C, Castellano G.C, Gianolio E.C, Pagliarin, R.C; pH-Dependent modulation of relaxivity and luminescence in macrocyclic Gd and Eu complexes based on reversible intramolecular sulfonamide ligation. Journal of the American Chemical Society, 2001, 123 (31), 7601-7609. https://doi.org/10.1021/ja0103647
 

6. Reany, O.PD, Gunnlaugson, T.C, Parker D.PI; A model system exhibiting modulation of Ln luminescence to signal Zn+2 ions in competitive aqueous media. Journal of the Chemical Society Perkin Transaction 2, 2000, 9, 1819-1832. https://doi.org/10.1039/B003963Mhttps://doi.org/10.1039/A909906I

 
5. Reany, O.PD, Blair, S.C, Kataky, R.PI, Parker D.PI; Solution complexation behaviour of 1,3,5-trioxacyclohexane based ligands and their evaluations as ionophores for group Ia/IIa metal ions. Journal of the Chemical Society Perkin Transaction 2, 2000, 4, 623-630. https://doi.org/10.1039/A909906I
 

4. Reany, O.PD, Gunnlaugson, T.C, Parker D.PI; Selective signaling of zinc ions by modulation of terbium luminescence. Chemical Communication, 2000, 473-474.  https://doi.org/10.1039/B000283F

 
3. Galasso, V.S, Jones, D.PI, Reany, O.S, Ganguly, B.PD, Abramson, S.C, Fuchs B.PI; Theoretical study of the molecular structure and spectroscopic properties of 1,7:3,5-dimethylene-cis-1,3,5,7tetraazadecalin. Journal of Molecular Structure. THEOCHEM, 1999, 491,187-191. https://doi.org/10.1016/S0166-1280(99)00109-8
 
2. Reany, O.S, Goldberg, I.C, Abramson, S.C, Golender, L.C, Ganguly, B.PD, Fuchs B.PI; The 1,3,5,7-tetraazadecalins: structure, conformation, and stereoeelectronics. Theory vs. experiment. Journal of Organic Chemistry, 1998, 63, 8850-8859. https://doi.org/10.1021/jo9809884
 

1. Reany, O.S, Grabarnik, M.C, Goldberg, I.C, Abramson, S.C, Star, A.S, Fuchs B.PI; trans and cis1,3,5,7-Tetraazadecalin (TAD): a new & strong binding mode in cis-tad chelates of heavy metal ions. Tetrahedron Letters, 1997, 38, 8073-8076. https://doi.org/10.1016/S0040-403997)10111-3

 

 

1. Reany O.PI,* and Keinan E. PI "Machines, switches and delivery devices based on cucurbit[6]uril and bambus[6]uril" in Cucurbiturils and Related Macrocycles: Monographs in Supramolecular Chemistry Series, Kim K. (Ed), RSC, Chap. 11, 2020 pp. 283-323.

1. Dolitzky, B., Reany, O., Wizel, S., Shammai, J.; Crystalline Solid Famciclovir Forms I, II, III and Preparation thereof; US Patent 2004/0097528 A1, Published date: May 20, 2004.


2. Dolitzky, B., Reany, O., Shammai, J.; Novel Process for Preparing & Isolating rac-Bicalutamide & Its Intermediates; US Patent 2004/0044249 A1, Published date: March 4, 2004.

 

 The exchange of anions between the living cell and its environment represents one of the most fundamental life-sustaining phenomena, and many diseases are associated with defected chloride anion transport. Hence, the design of synthetic anion transporters and channels is essential not only for gaining insight on how natural ion carriers and channels work, but also for practical applications such as treatment of channelopathies, supramolecular architecture, anion sensing, catalysis and therapeutics.

A. hetero-Bambusurils
 
 
Scheme. 1. hetero-BU[n]s that we prepare by heteroatom displacement approach
 
B. Studying the unique structure of hetero-Bambusurils
 
The fused bicyclic structure of glycoluril is a valuable structural motif for a wide variety of cyclic host molecules. The bambusurils (BUs) are comprised of N,N-disubstituted glycoluril units, which are interconnected by only one hoop of single bonds ("single-stranded"). Although being single-stranded, the BUs are relatively rigid molecules due to their subunits high steric demands, which are locked in an alternate arrangement. In the BUs, the glycoluril units present their convex face towards the interior, forming a bamboo-like object. This structure explains why the BUs are anion-binders.
 
 
BUs are known to be rigid cavitands that feature an extended, jigger-like conformation, and the BU[6]s strongly bind anions within their hydrophobic cavity. The family of perthio-BUs, does not necessarily share these features. This study reveals that the latter assumes a compact conformation and perthio-BU[6]s are poor anion-binders, crystallizing as anion-free species from solutions containing halide salts. Computational studies show that the equatorial sulfur atoms compete against guest anions for binding with the glycoluril methine groups via strong vdW attractive interactions. These competitive contacts account for the diminished anion-binding of perthio-BUs, account for the diminished anion-binding of perthio-BUs, account for the diminished anion-binding of perthio-BUsaccount for the diminished anion-binding of perthio-BUs and explain their compact conformation.
 
 
 
 
Scheme 2. Solid-state structures of BU[6] (left) and BU[6] (right) heteroisomers. A. all-oxygen; B. ax-semithio-; C. ax-semiaza-; D. perthio-; E. computed structure of eq-semithio- and F. ax-semiaza-eq-semithio-. All molecules are characterized by a Capped Sticks model whereas all heteroatoms are represented by a Spacefill model (oxygen, red; sulfur, yellow; nitrogen, blue).
 
C. Unique reactivity and binding properties of sulfur-containing BU[4]s
 
The semithio- and perthio-BU[4]s form linear coordination polymers with Hg(II) in the solid-state regardless of their intrinsic molecular conformation. The strong involvement of sulfur atoms in intramolecular interactions differentiates the equatorial from the axial (peripheral) heteroatoms, thus offering chemoselective and regioselective transformations.
 
  
 
Fig. 1 Comparison between the crystal structures of the linear chains of Hg(II) complexes with semithio- (left) and perthio-BU[4] (right) in the solid state. 
 
D. From a single anion receptor into a potential anion channel
 
We show that by converting a semithio-bambus[6]uril into the corresponding semiaza-bambusuril, a single anion receptor is transformed into a potential anion channel. Hence, semiaza-BUs were found to simultaneously accommodate three anions, which were linearly positioned within the cavity along the cavitand's central symmetry axis (Fig. 2).
 
 
 
Fig. 2 Left: Solid-state structure of semithio-BU[6], 43 hosting a bromide anion. Middle and Right: Solid-state structure of two semiaza-bambusurils, 44 (R = H, top) and 44 (R = picolyl; bottom), hosting one bromide (top) or iodide (bottom) and two triflate anions. 
 
The solid state structure of semithio-BU[6] highlighted the bromide-binding site's immediate environment, indicating very close interactions between the anion and the twelve methine hydrogens, which were arranged in two circles above and below the bromide ion. The structures of semiaza-BU[6] are much more interesting in ion transport because the latter can accommodate several anions simultaneously. These complexes demonstrate a remarkable capacity of overcoming the strong electrostatic repulsion among three anions held together at a significantly small distance, as short as 4 Å. It is noteworthy that precisley the same inter-anionic distance of 4 Å was reported for adjacent chloride binding sites in the crystal structures of two mutant E. coli ClC chloride channels.
 
 
E. semithio-BU[6]: a transmembrane anion transporter.
 
Ion transport across the cell membrane is essential for maintaining the cell ion homeostasis and regulating critical processes of life, such as proliferation, differentiation and apoptosis. Generally, nature achieves these tasks using membrane proteins and large macromolecular assemblies. Synthetic small molecules, which function as ion transporters, offer exciting opportunities in biology and medicine. Such molecules could be used as therapeutic agents for treating anion channelopathies. Anion transporters can also induce apoptosis in cancer cells with potential applications in anticancer therapy. In a collaborative study with Prof. Junqiu Liu from Jilin University in China, we demonstrate the transporting ability of semithio-BU[6] as anion carriers through bilayer lipid membrane (POPC) with high selectivity to chlorides over various different anions (Fig. 3).
 
 

                                                                                                                                                                                                                                                                                                                                

Fig. 3 (A) Schematic view of the Clˉ influx and NO3ˉ efflux across POPC vesicles, monitored by lucigenin fluorescence; (B) chloride transport mediated by various BUs; (C) chloride transport of semithio-BU[6] (10 ml in DMSO solution, 2.7 mol%) using the potential-sensitive dye safranin O (Ex. 480 nm, Em. 520 nm) with various anions (DMSO was used as blank). 

 

 semithio-BU[6] is a significantly more efficient chloride transporter through bilayer lipid membranes than all other analogs due to their significant lipophilic variability. The transport efficiency was independent of the cation identity, indicating that the observed phenomena reflect anion-anion antiport rather than a symport mechanism. Moreover, semithio-BU[6] operates as a uniport transporter of chloride anions in the presence of phosphate and bicarbonate anions. These remarkable findings reflect this carrier's ability  to act as a valinomycin-like transporter, which could be exploited in biomedical applications..

 
F. Anchoring and packing of self-assembled monolayers (SAMs) of semithio-BUs on gold surface
 
Much attention has been received to thiolated SAMs because of their electrochemical sensing behavior and molecular electronic properties. Opposed to thiols, thiocarbonyl binding to gold surface results in forming a new bond rather than the replacement of an existing one (i.e., from RS-H to RS-Au). Surprisingly, SAMs based on macrocycles with docking thiocarbonyl groups have rarely studied. However, small closed-shell molecules with thiocarbonyl docking groups have shown induced radical character upon binding to the gold surface leading to higher conductance than thiolate analog.
In a collaborative study with Prof. Jurriaan Huskens from the University of Twente, Netherlands, a range of physicochemical characterization techniques combined with STM and MD simulations showed that semithio-BU[4] and semithio-BU[6] undergo significant conformational rearrangements upon attachment to a gold surface (Fig. 4). The molecules attach using most of the S atoms, with the energetic benefit of Au-S binding compensating for any steric strain. Accordingly, the molecule is forced to adopt a more confined/pinned conformation on the surface.
 
 
 
 
Fig. 4 STM images of a SAM of semithio-BU[4] (Left) and semithio-BU[6] (Right) on Au(111). Left: (a) Large scale topographic image (100 x 100 nm2, scale bar is 20 nm), taken at 250 pA and 700 mV. (b) STM image of a rectangular ordered domain (5.2 x 5.2 nm2, scale bar 2 nm). (c) The corresponding FFT of (b) showing rectangular symmetry. (d-e) STM height profile of the white and blue line in (b). (f) Proposed 4x2√3 unit cell (red rectangle, 1.15 x 1 nm2) of semithio-BU[4] on the unreconstructed Au(111) surface. Right: (a) Large scale topographic image (100 x 100 nm2, scale bar is 20 nm), 190 pA and 600 mV. (b) STM image of a hexagonal ordered domain (9.2 x 9.2 nm2, scale bar 3 nm). (c) The corresponding FFT of (b) showing the same hexagonal symmetry with a 0.86 nm periodicity (red) and hexagonal symmetry with a periodicity of approximately 1.5 nm (green). (d) STM height profile of the white line in (b) confirming a 0.86 nm distance between the sulfur atoms. (e) Proposed (3√3x3√3)R30o unit cell (green hexagon) of semithio-BU[6] on Au(111) with the (3x3) sulfur hexagon marked in red (0.86 x 0.86 nm2).
 
 G. Inherently chiral bambusurils
 
Chirality in macrocycles with large cavities has attracted significant attention due to their extensive use in chiral recognition, especially in their role in resolving racemates and in selectively transporting chiral guests through bulk liquid membrane technologies. Bambusurils (BUs) are rigid achiral macrocycles, exhibiting Sn point group of symmetry. A general criterion for chirality is the absence of any improper symmetry elements, i.e. Sn, including mirror image s, or a center of inversion, i. As such, these cavitands can be made chiral by either appending an intrinsically chiral functionality to the macrocyclic backbone or by using a non-symmetric subunit to produce stereogenic cavitands (Scheme 2). Therefore, designing inherently chiral hetero-BUs would be appealing for developing applications in the field of chiral sensing technologies. Recently, we introduced a new class of bambus[4]urils (BU[4]s) composed of asymmetric N,N’-disubstituted glycoluril subunits with different alkyl groups were prepared. Accordingly, four macrocyclic diastereoisomers are possible: two Sn symmetric achiral macrocycles and two macrocycles that are “inherently” chiral (Scheme 3). Indeed, if one of the methyl groups in glycoluril is substituted by a different group, then a mixture of two enantiomers is obtained. The cyclotetramerization of the glycoluril racemate with paraformaldehyde generates four possible stereoisomers of R'4Me4BU[4] (R'¹Me).
 
 
 
 
Scheme 3. BU[4] exhibiting four possible diastereoisomers: two of which are symmetric achiral (S4 and S2 symmetry), and two "inherently" chiral macrocycles (C1 and C2 symmetry).
 
The relative "head-to-tail" arrangement of the N-substituents in Bn4Me4BU[4] with S4 symmetry was fully confirmed by X-ray spectroscopy analysis. Chiral HPLC resolved the chiral Pr4Me4BU[4] (C1 symmetry into its enantiomers. All four inherently chiral bambusuril pairs of Pr4Me4BU[4] and Bn4Me4BU[4] stereoisomers were resolved by 1H NMR spectroscopy with the aid of (R)-BINOL as a chiral solvating agent. This latter methodology provides a rapid and robust approach for investigating inherently chiral cavitands' enantiopurity, which complements conventional chromatographic techniques.
 
H. Cucurbiturils
 
We have also focused on the binding properties of cucurbit[6]uril (CB[6]). This cavitand has attracted our attention for several years because it features a highly symmetric structure with high electron density at the carbonyl oxygen atoms on the cavitand rims and clearly illustrates its cation-receptor functionality. The cavitand's entry also leads to an entirley hydrophobic interior, which resulted in threading of neutral, highly hydrophobic alkyl chains. In this context, we prepared five homologous bis-α,ω-azidoethylammonium alkanes, where the number of methylene groups between the ammonium groups ranges from 4 to 8 (Fig. 5 top: complexes of 2-6@CB[6]). While the distance between the portal plane and most atoms at the guest end-groups increases progressively with the molecular size, the β-nitrogen atoms of the azide groups maintain a constant distance from the portal plane in all homologues, pointing at a strong attractive interaction between the azide group and the portal (Fig. 5 bottom).
In collaboration  with the research group of Prof. Michael K. Gilson (UCSD), we were able to show by quantum computational analyses that strong electrostatic interactions in the form of orthogonal dipole−dipole interaction are the main driver for this attraction. In contrast, the alternative mechanism of n → π* orbital delocalization did not seem to play a significant role in this interaction. The computational studies also indicate that the interaction is not limited to azides, but generalizes to other isoelectronic heteroallene functions, such as isocyanate and isothiocyanate.
 
 
  
  
Fig. 5. Top: X-ray crystal structures of (a) 2@CB[6], (b) 3@CB[6], (c) 4@CB[6], (d) 5@CB[6], and (e) 6@ CB[6]. CB[6] is presented in a cross-sectional, space-filling format. Atom doubling and missing bonds indicate disordered structures; Left bottom: Scatter plot correlation between θ (deg) and dN···O (Å), extracted from the X-ray structural data. The red circles refer to the interactions with the azide β-nitrogen atom, and blue circles refer to the γ-nitrogen; Right bottom: Scatter plot correlation between θ and dN···O (all referring to the azide β-nitrogen) extracted from the CSD database. The red circles refer to intramolecular interactions, whereas the red circles with a dark margin describe intermolecular interactions.
 
I. Multifarenes
 
The most common cavitands, are all homo-cyclooligomers of a single building block. Consequently, their binding properties, substitution patterns, functionalization, and solubility reflect the monomeric unit's characteristics.  In contrast, the hetero-cyclooligomeric cavitands multifarenes (MFs), which comprise multiple building blocks, are much more versatile in shape, size, rigidity and solubility and binding properties (Scheme 4).
 
 
 
 
 Scheme 4. Top: General design elements of MF[2,2] and Bottom: Gradual evolution of curved multifarenes by stepwise synthetic modifications
 
Recently, we reported the stepwise evolution of curved multifarene structures from planar precursors and increasing the extent of curvature in a controlled manner. These synthetic steps highlight three architectural design elements: a) employment of different aromatic units and changing their relative orientation, b) changing the hybridization of the linking atoms from sp2 to sp3, and c) rigidification of the non-planar system by 5-membered rings. These design elements are reminiscent of those used to transform flat graphene sheets into curved carbon structures, such as fullerenes and carbon nanotubes.
 

 

 

 
 In collaboration with the research group of Prof. N. Gabriel Lemcoff we utilize olefin metathesis as a synthetic tool for directing and controlling photochemical orthogonality and applications such as functional 3D-printing by developing new dicyclopentadiene (DCPD) based thermosets. We also investigate systematically new crosslinked polymers using α-substituted DCPD derivatives as monomers and studying their thermal and mechanical properties. In this context we also anticipated that employing flexible catenane linkages within the polymer chain might result in dynamic assembly and in substantial alteration of their mechanical and physical properties compared to the ubiquitous linear polymeric analogs. Our group is strongly involved in synthesizing of [3]catenanes and their incorporation within a linear chain of polymers. Finally, we also focus on the development of sustainable chemical transformations.
 
A. Metathesis reactions using photo-switchable catalysts
 
A1. Bichromatic selective access to levulinates and butenolides
We offer a new methodology to control a divergent tandem photochemical reaction's selectivity using light-absorbing organic molecules ("sunscreen" effect). Allylic and acrylic substrates were efficiently transformed by a sequential bichromatic photochemical process into derivatives of levulinates or butenolides with high selectivity when phenanthrene is used as a regulator (scheme. 5).

 

 

 

 Scheme. 5 Bichromatic selective divergent reaction

 

Delaying the double bond migration by employing phenanthrene as UV-C filter or hindering cyclization by using bulky substituents results in a highly selective tandem divergent all-photochemical pathway for the synthesis of fundamental structural motifs of widely occurring classes of natural products (Scheme. 6).

 

 
 
 
Scheme 6. Application of a divergent photochemical sequence in total synthesis.
 
A2. Light guided olefin metathesis reactions
 
The insertion of supersilyl protecting groups on the N-heterocyclic carbene (NHC) ligand in a light activated S-chelated ruthenium catalyst provides a synthetic way to act as an irreversible chromatic kill switch, thus decomposing the catalyst when it is irradiated with 254 nm UV light. The possibility to induce and impede catalysis just by using light of different frequencies was also tested for stereolithographic applications (Scheme. 7).
 
 
 
Scheme. 7 Dual chromatic control of precatalyst activation/deactivation in PROMP reactions. Polynorbornene as obtained from the metallic molds: 6 M monomer solution in DCM and 0.05%-mol of precatalyst.
 
The approach of using light to guide reactions is also demonstrated on a two-step bichromatic synthesis of coumarins. The first step was a UV-A-photoinduced ruthenium-catalyzed cross-metathesis (CM) reaction of 2-nitrobenzyl-protected 2-hydroxystyrenes with acrylates, using an external solution of 1-pyrenecarboxaldehyde as a UV filter. Irradiation in the absence of the filter permanently inhibited the light-activated catalyst due to photocleavage of the photolabile protecting group (PPG) and ensuing phenolate chelation to the ruthenium. The simple removal of the external filter after CM allowed further photochemical reactions with UV-C light to achieve more complex coumarins architectures (Scheme. 8).
 
 

 

 
Sceme 8. op: UV filter-assisted light-induced CM reactions of 2-nitrobenzyl protected 2-hydroxystyrenes. Bottom: UV-filter-assisted, two-step photochemical synthesis of coumarins.
 
B. Tuning thermomechanical properties of crosslinked polymers
 
In this project we examine the implementation and application of ring-opening metathesis polymerization (ROMP) using dicyclopentadiene (DCPD) derivatives (Scheme 9) that will be incorporated into commercial ink formulations and can be applied in 3D-printing techniques to produce printed circuit boards or printed 3D structures for medical applications. The innovation compared with what has been done in the field relies on the crosslinked type polymers with several significant advantages over other existing polymers in the development and commercialization of ink formulations. These advantages include the high mechanical strength and thermal stability over a broader range of temperature and pressure; prevention from unpleasant odors that characterize other polymers such as lactic poly-acid or polyacrylate-styrene mixture; no use of additives or impact modifiers, and the fastest polymerization among non-radical processes.
The mechanical properties of the produced polymers are examined by changing several parameters, such as initiator type and loading, monomer/s chemical structure, and the use of heat or light-based curing methods is of great interest. Consequently, the project involves synthesis and DMA analyses of a library of homo- and co-polymers based on four different DCPD monomers, which various ruthenium initiators obtain. The trends observed in this study may be used to control the crosslinking (curing) process for industrial applications and other end-user products that contain integrated polymeric devices.

 

 

 
 

  Scheme 9. Ruthenium catalyzed polymerization of DCPD derivatives.

 

 C. [3]catenane-based polymers with unprecedented relaxation modes 
The polymers we know are mostly made by covalent chemical bonds between their monomers. In this research, we aim at using monomers based on mechanically bonded [3]catenanes as an alternative and new way for the construction of polymers. It is anticipated that employing flexible catenane linkages within the polymer chain might result in dynamic assembly and in significant alteration of their mechanical and physical properties in comparison to the ubiquitous linear polymeric analogs.
 
 
 
 
This project includes:
1) Synthetic paths to the primary [3]catenane monomeric units, which are essential for the preparation of main-chain poly-[3]catenane.
2) Synthesis of polymers that contain the [3]catenane unit (Fig. 6, left).

3) Probing free rotation of the internal macrocycle in [3]catenane by AFM (Fig 6, right).

 
 

 

 

  

 

 Fig. 6 Force-extension traces of the [3]catenane based polymer carried out with a Cypher-ES AFM (Asylum research/Oxford Instruments). Simple force- curves were realized using silicon nitride cantilevers with a nominal spring constant of 0.07 N m-1. Red trace showed the approach of the tip towards the substrate surface (approach curve). Blue trace demonstrates the PEO tether is caught by the AFM tip and stretched by moving the tip away from the surface (retraction curve). The black arrows indicate the peaks suggested for changes in the positioning of one mechanically interlocked component with another.

  D. Highly sustainable halogenation of alcohols
 
We have developed a new synthetic methodology to afford halogenation of alcohols under mild conditions and accelerated by the presence of sub-stoichiometric amounts of thiourea (Scheme 10). The amount of thiourea added dictates the reaction's pathway, which may diverge from the desired halogenation reaction towards oxidation of the alcohol, in the absence of thiourea, or towards starting material recovery when excess thiourea is used.
 
Both brominations and chlorinations were highly efficient for primary, secondary, tertiary and benzyl alcohols and tolerated a broad range of functional groups. Detailed EPR studies, isotopic labeling and other control experiments suggest a radical-based mechanism. The fact that the reaction is carried out at ambient conditions, uses ubiquitous and inexpensive reagents, boasts a broad scope, and can be made highly atom-economy, making this new methodology a very appealing option archetypical organic reaction
 
 
  
Scheme 10. How to make organic chlorides and bromides.
 

Nebal Alassad


M.Sc. student
2020 –

nebala@post.bgu.ac.il

  
   Habib Assy


M.Sc. student
2020 –

assyh@post.bgu.ac.il

Dr. Satheesh Vanaparthi


Post-doctoral researcher
2020 –

vanaparthi.satheesh@gmail.com

  
   Dr. Raman Khurana


Post-doctoral researcher
2020 –

raman.khurana90@gmail.com

Dr. Pooja Dubey


Post-doctoral researcher
2019 – 2020

poojaddayal.75@gmail.com

  
   Dr. Amar Mohite


Post-doctoral researcher
2015 – 2020

armohitept@gmail.com

  
   Dr. Pravat Monda

l
Post-doctoral researcher
2017 – 2019

pravat122@gmail.com

   Dr. Revannath Sutar


Post-doctoral researcher
2014 – 2018

revannath.sutar@gmail.com

  
   Dr. Mandeep Singh


Post-doctoral researcher
2012 – 2015

mandeepchemical@gmail.com



Gallery

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    Invited speakers and chairs were celebrating 70th Prof. Ehud Keinan's birthday, Technion, 2017. From left to right: Dr. Sigal Saphier, Dr. Noam Greenspoon, Prof. Ilam Marek, Prof. Yitzhak Apeloig, Prof. Doron Shabat, Prof. Norman Metanis, Prof. Ashraf Brik, Prof. Ehud Keinan, Prof. Ofer Reany, Dr. Doron Eren, Prof. Subhash Sinha, Prof. Flavio Grynszpan, Dr. Ephrath Solel, Prof. Ron Piran, Prof. Doron Pappo, Prof. Mark Gandelman and Prof. Timor Baasov.

     

     

    During lunch break with Prof. Ehud Keinan and Prof. Ashraf Brik

     

     

     

    Program of "Chemistry and Beyond" conference.

     

     

    Celebrating Prof. Keinan's birthday: dinner at Hakeves Restaurant (Osafia). Left to right: Liraz, Ofer Ehud, Doron P., Doron S., Ilan, Ilan's son, and Yitzhak.

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    Israel delegation, The 5th International Conference in Cucurbiturils (ICCB-5), Berno, 2015. From left to right: Dr. Amar Mohite, Ms. Delana Mikolasova (Czech representative), Dr. Chinna Swamy, Prof. Vladimir Sindelar, Prof. Rafal Klajn, Czech representative, Prof. Amnon Bar-Shir, Dr. Liat Avram, Prof. Yoram Cohen, Prof. Ofer Reany, and Prof. Ehud Keinan

     

     

    Explaining the science to Czech representative, Ms. Delana Mikolasova, during Poster Session

     

     

     

    Invited lecture on "identification of new binding mechanism accessible to cucurbiturils: attractive interactions between heteroallens and the CB portal."

     

     

     During poster session together with (from left to right) Dr. Amar Mohite (postdoc), Ms. Delana Mikolasova (Czech representative), and Dr. Chinna Swamy (postdoc).

     

     

     

    A meeting with Prof. Jinqui Liu (Jilin University) at the the 23rd international conference on physical organic chemistry (ICPOC-23), Sydney, Australia, July, 2016.

     

     

    ETH Zurich (Zentrum) hosting the 22nd international symposium on olefin metathesis and related chemistry (ISOM22), July 2017.

     

     

     

    Together with (from left to right) Gal Segalovich, Victoria Kobernik, Alexander Frenklah, Or Eivgi, and Illya Rosenberg (Prof. Lemcoff's research lab students).

     

     

    With Prof. Gabriel Lemcoff (Gabi).

     

     

    An afternoon break in Zurich city center with Gabi.

     

     

    Excursion to Lagos and Sagres with (left to right): Prof. Sebastian Kozuch (BGU), Dr. Renana Poran (ETH, postdoc) and Dr. Ephrath Solel (BGU, postdoc) during the 24th international conference on physical organic chemistry (ICPOC-24), Faro, Portugal, July 2018.

     

     

     

    With Dr. Pravat Mondal (postdoc) in excursion during the 24th international conference on physical organic chemistry (ICPOC-24), Faro, Portugal, July 2018.

     

     

     

    A conference banquet during the 6th international conference on cucurbiturils (ICCB-6) in Ohio University, July, 2019. Around the table from left to right: Prof. Yieng-Wei Yang (Jilin Uni.), Prof. Werner Nau (Jacobs Uni.), Prof. Lyle Isaacs (Maryland Uni), Prof. Eric Masson, (Ohio Uni.), Prof. Michael Pittelkow (Copenhagen Uni.), Prof. Kimoon Kim (POSTECH, ahead of the table), then Prof. Riina Aav (Tallin Uni.), Prof. Ofer Reany (OUI), and Prof. Ehud Keinan (Technion).

     
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    Together with Prof. Ehud Keinan and postdocs in "Organic Synthesis in the Negev" (Adama-BGU day symposium, 2016). From left to right: Dr. Srinivas Samala, Dr. Revannath Sutar, Dr. Amar Mohite, Dr. Pravat Mondal, and Dr. Chinna Swamy.

     

     

     

    The lab in Technion…

     

     

    Dr. Satheesh Vanaparthi explains to Neta, a project student, how to prepare semithio-banbusuril.

     

     

    Farewell dinner to Dr. Mandeep Singh (right), the first postdoc in the group and PBC fellowship winner, Haifa 2016.