Carbon–Carbon Bond Cleavage in Fluorescent Pyronin Analogues Induced by Yellow Light
摘要:
A novel class of pyronin analogues, which undergoes a photochemically induced cleavage of the C-C bond in the presence of water in both solution and on a silica gel surface upon direct irradiation with visible fight, is reported. The reaction course can be monitored by characteristic fluorescence of both the starting compound and the final product. This system could find useful applications in the field of photoremovable protecting groups or caged fluorophores.
A wide range of prochiral 1,3-diamines were first efficiently synthesized and subsequently desymmetrized by using lipase from Pseudomonas cepacia as catalyst and diallyl carbonate as alkoxycarbonylating agent. In all cases, the amino carbamates of R-configuration were recovered. Final selective cleavage of the N-allyloxycarbonyl moiety was carried out under mild reaction conditions, which demonstrates
Use of hexamethylphosphoramide chmpa in the alkylation of aromatic amines: synthesis of azetidines, pyrrolidines, piperidines and hexahydroazepines
作者:Eusebio Juaristi、Domingo Madrigal
DOI:10.1016/0040-4020(89)80091-2
日期:1989.1
The direct alkylation of -toluidine, as a model of aromatic amines, with 1,3-, 1,4-, 1,5- and 1,6-ditosylates, -dibromides or -dimesylates in HMPA as solvent affords the corresponding cyclic amines. The convenience of this reaction and some observed limitations are discussed.