Wide Rim Urethanes Derived from Calix[4]arenes: Synthesis and Self-Assembly
作者:Yudong Cao、Myroslav O. Vysotsky、Volker Böhmer
DOI:10.1021/jo0524369
日期:2006.4.1
Calix[4]arenes4, substituted at the wide rim by four N-tolyl-urethane groups, were synthesized, as well as derivatives 10a,b bearing two or three tolyl-urea groups beside of one or two urethane group(s). In contrast to tetra-tolyl urea 11, the urethane derivatives do not form hydrogen-bonded, dimeric capsules in CDCl3 or benzene-d6, but the dimerization can be induced for the triurea 10b by tetraethylammonium