Premium
Diastereoselective Noncovalent Synthesis of Hydrogen‐Bonded Double‐Rosette Assemblies
Author(s) -
Prins Leonard J.,
Hulst Ron,
Timmerman Peter,
Reinhoudt David N.
Publication year - 2002
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/1521-3765(20020517)8:10<2288::aid-chem2288>3.0.co;2-3
Subject(s) - chirality (physics) , stereochemistry , chemistry , non covalent interactions , hydrogen bond , crystallography , materials science , chiral symmetry , molecule , physics , organic chemistry , quantum mechanics , nambu–jona lasinio model , quark
Chiral centers present either in the dimelamine components of calix[4]arene 1 or in the cyanurate components CA quantitatively induce one handedness ( P or M ) in the corresponding hydrogen‐bonded assemblies 1 3 ⋅ (CA) 6 ( de >98 %). The high degree of chiral induction results from the presence of six chiral centers in close proximity (C α ) to the core of the assembly. A much lower level of chiral induction is observed for assemblies with chiral centers that are more remote (C β ). All diastereomerically pure assemblies 1 3 ⋅ (CA) 6 exhibit very high CD activities (|Δ ε max |∼100 L mol −1 cm −1 ), in sharp contrast to the low CD activities (|Δ ε max |≤8 L mol −1 cm −1 ) shown by the free components. The assemblies display spontaneous resolution under thermodynamically controlled conditions (i.e., heteromeric assemblies containing both peripheral R and S centers are not observed. Remarkable assembly behavior is observed if both components 1 and CA are chiral. In general, formation of well‐defined assemblies is only observed when both components contain unidirectional information for the induction of either M or P chirality.