The first example of the generation of azomethine ylides from a fluorocarbene: 1,3-cyclization and 1,3-dipolar cycloaddition
作者:Alexander S. Konev、Mikhail S. Novikov、Alexander F. Khlebnikov
DOI:10.1016/j.tetlet.2005.09.165
日期:2005.11
or dimethyl acetylenedicarboxylate, the products of dehydrofluorination of the primary adducts of the 1,3-dipolarcycloaddition of fluoro-substituted azomethine ylides to multiple bonds of dipolarophiles were obtained. In the case of the reaction of N-alkylimines of benzaldehyde the cycloaddition of ylides to dimethyl maleate completely suppressed the cyclization to aziridines.
A simple route to side-chain fluorinated β-lactams from ring-fluorinated aziridines
作者:Alexander S. Konev、Mikhail S. Novikov、Alexander F. Khlebnikov、Kourosch Abbaspour Tehrani
DOI:10.1016/j.jfluchem.2006.10.013
日期:2007.2
beta-Lactams bearing a Ph2CF substituent at the C(4)-atorn were synthesized from N-alkyl-2-fluoro-3,3-diphenylaziridines. The transformation was realized using SbF3-mediated isomerization of the monofluoroaziridines to fluorinated aldimines, followed by Staudinger reaction with ketenes. It was shown that this reaction sequence can be performed as a one-pot procedure. (c) 2006 Elsevier B.V. All rights reserved.
Monofluoro-substituted azomethine ylides in fluorocarbene reactions with imines. Synthesis and transformations of monofluoroaziridines
作者:A. S. Konev、M. S. Novikov、A. F. Khlebnikov
DOI:10.1134/s1070428007020224
日期:2007.2
N-Arylmethylene and N-benzhydrylideneamines react with fluorocarbene yielding fluoro-substituted azomethine ylides that undergo 1,3-pi-cyclization into aziridines. Generation of fluoroylides in the presence of dipolarophiles (dimethyl maleate or dirnethyl acetylenedicarboxylate) led to the reaction of 1,3-dipolar cycloaddition resulting in substituted 2-pyrrolines or pyrroles. 2-Fluoroaziridines, products of N-alkyl-N-benzhydrylideneamines 1,3-pi-cyclization, in the presence of acid catalysts suffer isomerization into alpha-fluoroimines and 1,3-disubstituted indoles.
Fluoroaziridines as novel substrates in the modified Petasis reaction: synthesis of monofluorinated propargyl amines
作者:Alexander S. Konev、Sara Stas、Mikhail S. Novikov、Alexander F. Khlebnikov、Kourosch Abbaspour Tehrani
DOI:10.1016/j.tet.2007.10.067
日期:2008.1
Reaction of 2-fluoroaziridines with potassium alkynyltrifluoroborates in the presence of BF3·OEt2 leads to fluorinated propargyl amines in moderate to good yields. The reaction proceeds as an in situ isomerization of 2-fluoroaziridines to α-fluorinated imines, followed by the reaction of the imine with alkynyldifluoroborane, which is generated in situ from the potassium alkynyltrifluoroborates and