Protection of a protecting group: Preparation of stable N-silylated t-butyl carbamates
作者:Johanne Roby、Normand Voyer
DOI:10.1016/s0040-4039(96)02271-x
日期:1997.1
The practical preparation of N-silylated carbamates (typified by 1) is reported. These compounds are synthesized in high yields by treating N-t-Boc-protected primary amines with silyl triflate reagents in dichloromethane in the presence of triethylamine. Copyright (C) 1996 Elsevier Science Ltd
Rapid access to N -Boc phenylglycine derivatives via benzylic lithiation reactions
novel and efficient method for the enantioselective synthesis of N-Boc protected phenylglycines. Yields and enantiomeric ratios vary widely depending on the nature of the solvent, the substrate and on the method of forming the chiral complex. Results show that the major reaction pathway is an enantioselective deprotonation/substitution process. The enantioselectivity appears to be limited by the chiral
Preparation of enantioenriched α-silyl-benzylcarbamates
作者:Claude Barberis、Normand Voyer
DOI:10.1016/s0040-4039(98)01463-4
日期:1998.9
enantioselective [1,2] silicon rearrangement are reported. This novel synthetic method lead to the formation of chiral α-substituted benzylamines with an α-silyl group. In the procedure, N-Silyl-protectedN-Boc benzylamines are subjected to enantioselective deprotonation using the chiral complex (−) sparteine. s-BuLi to generate chiral benzyllithium intermediates that undergo a [1,2] silicon shift.