Studies towards C-3 functionalization of β-lactams using substituted allylsilanes
作者:RENU THAPAR、RESHMA、S S BARI
DOI:10.1007/s12039-016-1161-6
日期:2016.11
An effective and stereoselective synthesis of 3-(1′-methyl/phenylallyl)-3-phenylthio-β-lactams (3/4) using substituted allylsilane and Lewis acid is described. The reaction leads to the formation of a mixture of C-3substituted allyl β-Lactams. However, these compounds on desulphurisation using tri-n-butyltinhydride and Raney Ni provide two separable diastereomers of the reduced product. In the presence
A new synthetic approach for spiro-β-lactams by cyclization of cis-3-allyl-3-benzylthio-β-lactams is presented. The reaction involves step-wise electrophilic addition-dealkylation sequence giving stereospecific synthesis of C-3-spiro-β-lactams.
A facile Lewis acid-promoted allylation of azetidin-2-ones
作者:S.S. Bari、P. Venugopalan、Renu Arora
DOI:10.1016/s0040-4039(02)02775-2
日期:2003.1
Exposure of 3alpha-chloro-3-phenylthioazetidin-2-ones and allyl trimethyl si lane to a Lewis acid promotes a remarkably facile and stereoselective C-3 allylation to give 3alpha-allyl-3-phenylthioazetidin-2-ones 4 in excellent yield. These allylated azetidin-2-ones undergo smooth desulphurization with tri-n-butyltin hydride or Raney-nickel producing cis-3-allyl- and cis-3-propylazetidin-2-ones. (C) 2003 Elsevier Science Ltd. All rights reserved.