Diphenylsilyldiethylene- (DPSide-) group: A new primary amine protection
作者:B. Moon Kim、Jong Hyun Cho
DOI:10.1016/s0040-4039(99)00970-3
日期:1999.7
Diphenylsilydiethylene- (DPSide-) group has been developed as a new primary amine protecting group. The new protecting group exhibits novel orthogonality against other commonly used amine-protecting groups and excellent chemoselectivity for unbranched a-amino acid esters. Removal of this protecting group was effected under mild fluoride-based cleavage conditions. (C) 1999 Elsevier Science Ltd. All rights reserved.
Enantioselective Synthesis of α-Fluoro-β<sup>3</sup>-amino Esters: Synthesis of Enantiopure, Orthogonally Protected α-Fluoro-β<sup>3</sup>-lysine
作者:Peter J. Duggan、Martin Johnston、Taryn L. March
DOI:10.1021/jo101600c
日期:2010.11.5
The scope of a tandem conjugate addition fluorination sequence performed on alpha,beta-unsaturated esters using the enantiopure lithium amide derived from (S)-N-benzyl-N-(alpha-methylbenzyl)amine, and the electrophilic fluorinating agent N-fluorobenzenesulfonimide has been investigated. Using this method, a-fluoro-beta(3)-amino esters can be obtained in up to quantitative yield and 80:20 to >99:1 dr. This simple methodology does not rely on the use of alpha-amino acids from the chiral pool and thus provides the potential for the preparation of enantiopure alpha-fluoro-beta(3)-amino acids with a wide variety of side chains. Its utility was demonstrated through the synthesis of orthogonally protected (2S,3S)-alpha-fluoro-beta(3)-lysine.