Scalable Synthesis of N-Acylaziridines from N-Tosylaziridines
摘要:
N-Acylaziridines are important starting materials for the synthesis of chiral amine derivatives. The traditional methods for producing these activated aziridines have significant drawbacks. The gram scale synthesis of N-acylaziridines by deprotection of N-tosylaztridines and reprotection with N-hydroxysuccinimide derivatives is described. Mono- and disubstituted aziridines perform well, with complete retention of stereochemical purity. The consistently moderate yields are linked to the N-tosylaziridine deprotection step, while acylation with N-hydroxysuccinimide derivatives is highly efficient.
Several synthetic strategies to diamines 1-3 are described. The optimum approach via opening of aziridine afforded 1 3 in 29-60% yield over 3-5 steps. A study on formation of the benzylic stereocenter using Toste's rhenium-catalyzed asymmetric reduction of phosphinyl ketimines was also evaluated and afforded 15 in 92% de. (c) 2007 Elsevier Ltd. All rights reserved.
Stereoselective synthesis of 2,5-disubstituted morpholines using a palladium-catalyzed hydroamination reaction
作者:Alicia McGhee、Brian M. Cochran、Torrey A. Stenmark、Forrest E. Michael
DOI:10.1039/c3cc44117b
日期:——
A palladium-catalyzed hydroamination reaction is the key step in a stereoselectivesynthesis of 2,5-disubstituted and 2,3,5-trisubsituted morpholines from carbamate-protected aziridines. Aziridines are selectively attacked at the more substituted position by unsaturated alcohol nucleophiles using Lewis acid catalysts. Palladium-catalyzed hydroamination of the resulting aminoalkenes gives morpholines
METHOD FOR PREPARING DIPEPTIDYL PEPTIDASE-IV INHIBITOR AND INTERMEDIATE
申请人:Kwak Woo Young
公开号:US20120016125A1
公开(公告)日:2012-01-19
The present invention relates to an improved method for preparing dipeptidyl peptidase-IV inhibitor and intermediate. The present invention is able to reduce preparation costs by using low cost reagents on reaction and is able to be used in mass production by improving yield.
Synthesis of novel N-protected β3-amino nitriles: study of their hydrolysis involving a nitrilase-catalyzed step
作者:Maité Sylla-Iyarreta Veitía、Pierre Louis Brun、Pierre Jorda、Annie Falguières、Clotilde Ferroud
DOI:10.1016/j.tetasy.2009.07.045
日期:2009.9
Several commercially available nitrilases were investigated with regard to their potential to hydrolyze N-protected beta(3)-amino nitriles into their corresponding N-protected beta(3)-amino acids.The biotransformations were obtained in different proportions depending oil the nitrilase involved The best hydrolysis results were achieved for the N-Cbz-beta(3)-amino nitrile from i-alanine using the NIT-107, in a phosphate buffer at 0 05 M However, no biotransformation into the corresponding acids was observed for the N-sulfonylamide beta(3)-amino nitriles. Two simple and efficient procedures to prepare the beta(3)-amino nitriles from their analogous alpha-amino acids are described Thirty four new substances were synthesized and characterized over the course of this work. (C) 2009 Elsevier Ltd All rights reserved