Enantiospecific synthesis of N-benzyl-2-alkyl pyrrolidines and piperidines mediated by chiral organoborane reagents
摘要:
A new general method for synthesizing N-benzyl-2-alkylpyrrolidines and N-benzyl-2-alkylpiperidines, having very high enantiomeric excess, has been achieved starting from aldehydes and organoborane reagents.
(S,S)-N,N-Bis(-α-methylbenzyl)formamide is the first example of chiral formamides that function as Lewis base catalysis to effectively serve catalytic asymmetricsynthesis. The chiral formamide in combination with an additive, HMPA, catalyzes allylations of aliphatic aldehydes with allyl- and crotyltrichlorosilanes with high enantioselectivity (up to 98% ee). In the crotylations with (E)-crotyltrichlorosilane
A new general method for synthesizing N-benzyl-2-alkylpyrrolidines and N-benzyl-2-alkylpiperidines, having very high enantiomeric excess, has been achieved starting from aldehydes and organoborane reagents.
Tietze, Lutz F.; Schiemann, Kai; Wegner, Christoph, Chemistry - A European Journal, 1996, vol. 2, # 9, p. 1164 - 1172
作者:Tietze, Lutz F.、Schiemann, Kai、Wegner, Christoph、Wulff, Christian