The preparation and alkylation of β-sultam mono- and dianions
作者:Michael J. Szymonifka、James V. Heck
DOI:10.1016/s0040-4039(00)99146-9
日期:1989.1
The reaction of 2-unsubstituted 1,2-thiazetidine-1,1-dioxides with n-butyllithium affords dianions which react with a variety of electrophiles. Selective mono- and dialkylation is readily accomplished.
MULLER, MARTIN;OTTO, HANS-HARTWIG, ARCH. PHARM., 324,(1991) N, C. 15-17
作者:MULLER, MARTIN、OTTO, HANS-HARTWIG
DOI:——
日期:——
Properties and Reactions of Substituted 1,2-Thiazetidine 1,1-Dioxides: Methylation of β-Sultams
作者:Martin Müller、Hans-Hartwig Otto
DOI:10.1002/ardp.19913240106
日期:——
Methylation of N‐substituted 1,2‐thiazetidine 1,1‐dioxides in the presence of lithium diisopropylamide (LDA) yields 4,4‐dimethyl derivatives. Monomethylation only occurs when one position at C‐4 is blocked by a silyl group, which, afterwards, can be removed by treatment with tetrabutylammonium fluoride (TBAF). A silyl protecting group at the nitrogen is easily removed by cleavage with TBAF on silica