Complexation of alkali metal cations by conformationally rigid, stereoisomeric calix [4] arene crown ethers: a quantitative evaluation of preorganization E Ghidini, F Ugozzoli, R Ungaro, S Harkema, A Abu El-Fadl, ...
Journal of the American Chemical Society 112 (19), 6979-6985, 1990
473 1990 Selective functionalization of calix [4] arenes at the upper rim JD Van Loon, A Arduini, L Coppi, W Verboom, A Pochini, R Ungaro, ...
The Journal of Organic Chemistry 55 (21), 5639-5646, 1990
427 1990 Kinetically stable complexes of alkali cations with rigidified calix [4] arenes: synthesis, X-ray structures, and complexation of calixcrowns and calixspherands PJ Dijkstra, JAJ Brunink, KE Bugge, DN Reinhoudt, S Harkema, R Ungaro, ...
Journal of the American Chemical Society 111 (19), 7567-7575, 1989
280 1989 The 1, 2-alternate conformation of calix [4] arenes: a rare conformation? Dynamic 1H NMR studies of flexible tetraalkylated calix [4] arenes LC Groenen, JD Van Loon, W Verboom, S Harkema, A Casnati, R Ungaro, ...
Journal of the American Chemical Society 113 (7), 2385-2392, 1991
234 1991 Angle-resolved phase-sensitive determination of the in-plane gap symmetry in YBa2 Cu3 O7−δ JR Kirtley, CC Tsuei, CJM Verwijs, S Harkema, H Hilgenkamp
Nature Physics 2 (3), 190, 2006
208 2006 Cocomplexation of neutral guests and electrophilic metal cations in synthetic macrocyclic hosts CJ Van Staveren, J Van Eerden, FCJM Van Veggel, S Harkema, ...
Journal of the American Chemical Society 110 (15), 4994-5008, 1988
205 1988 Functionalized UO2 salenes: neutral receptors for anions DM Rudkevich, W Verboom, Z Brzozka, MJ Palys, WPRV Stauthamer, ...
Journal of the American Chemical Society 116 (10), 4341-4351, 1994
203 1994 " Tert-Amino effect" in heterocyclic synthesis. Formation of N heterocycles by ring-closure reactions of substituted 2-vinyl-N, N-dialkylanilines W Verboom, DN Reinhoudt, R Visser, S Harkema
The Journal of Organic Chemistry 49 (2), 269-276, 1984
178 1984 syn-1, 2-dialkylated calix [4] arenes: general intermediates in the NaH/DMF tetraalkylation of calix [4] arenes LC Groenen, BHM Ruel, A Casnati, P Timmerman, W Verboom, ...
Tetrahedron letters 32 (23), 2675-2678, 1991
162 1991 Molecular-dynamics simulation of crystalline 18-crown-6: thermal shortening of covalent bonds J Van Eerden, S Harkema, D Feil
Acta Crystallographica Section B: Structural Science 46 (2), 222-229, 1990
162 1990 Thermodynamic constants of complexes of crown ethers and uncharged molecules and x-ray structure of the 18-crown-6.(MeNO2) 2 complex JAA De Boer, DN Reinhoudt, S Harkema, GJ Van Hummel, F De Jong
Journal of the American Chemical Society 104 (15), 4073-4076, 1982
158 1982 Tetra-O-alkylated calix [4] arenes in the 1, 3-alternate conformation W Verboom, S Datta, Z Asfari, S Harkema, DN Reinhoudt
The Journal of Organic Chemistry 57 (20), 5394-5398, 1992
152 1992 Uranyl UO2-salenes: neutral receptors for anions with a high selectivity for dihydrogen phosphate DM Rudkevich, WPRV Stauthamer, W Verboom, JFJ Engbersen, ...
Journal of the American Chemical Society 114 (24), 9671-9673, 1992
132 1992 Admixtures to HJH Smilde, AA Golubov, G Rijnders, JM Dekkers, S Harkema, ...
Physical review letters 95 (25), 257001, 2005
130 2005 Self-reproduction of chirality in carbon-carbon bond formation via dipolar intermediates generated in situ by [1, 5] hydrogen transfer WHN Nijhuis, W Verboom, DN Reinhoudt, S Harkema
Journal of the American Chemical Society 109 (10), 3136-3138, 1987
115 1987 Co-complexation of urea and UO22+ in a Schiff base macrocycle: a mimic of an enzyme binding site CJ Van Staveren, DE Fenton, DN Reinhoudt, J Van Eerden, S Harkema
Journal of the American Chemical Society 109 (11), 3456-3458, 1987
102 1987 International union of crystallography commission on charge, spin and momentum densities: project on comparison of structural parameters and electron density maps of oxalic … P Coppens, J Dam, S Harkema, D Feil, R Feld, MS Lehmann, R Goddard, ...
Acta crystallographica. Section A, Crystal physics, diffraction, theoretical …, 1984
102 1984 Stereochemical aspects of the" tert-amino effect". 1. Regioselectivity in the synthesis of pyrrolo [1, 2-a] quinolines and benzo [c] quinolizines WHN Nijhuis, W Verboom, A Abu El-Fadl, S Harkema, DN Reinhoudt
The Journal of Organic Chemistry 54 (1), 199-209, 1989
101 1989 Molecular dynamics of 18-crown-6 complexes with alkali-metal cations: calculation of relative free energies of complexation J Van Eerden, S Harkema, D Feil
The Journal of Physical Chemistry 92 (18), 5076-5079, 1988
95 1988 Macrocyclic trinucleating ligands for the cocomplexation of two" soft"(Cu2+, Ni2+, or Zn2+) metal centers and one" hard"(Ba2+ or Cs+) metal center FCJM Van Veggel, M Bos, S Harkema, H Van de Bovenkamp, ...
The Journal of Organic Chemistry 56 (1), 225-235, 1991
93 1991 