Efficient one-pot synthesis of 2-azetidinones from acetic acid derivatives and imines using methoxymethylene-N,N-dimethyliminium salt
摘要:
A cheap, versatile and convenient method for synthesis of beta-lactams using methoxymethylene-N,N-dimethyliminium salt as an acid activator in Staudinger reaction is reported. This method is used for the preparation of monocyclic, spirocyclic, N-alkyl and three-electron-withdrawing group beta-lactams. The products are obtained in good to excellent yields. (C) 2010 Elsevier Ltd. All rights reserved.
Cu-catalyzed three-component reaction of alkyne, azides (sulfonyl or phosphoryl azides), and N,N-dialkyloxyformamide dialkyl acetal via electrophilic addition of immonium ion to copper ketenimine is reported. This new protocol for the preparation of α,β-unsaturated amidine derivatives appears to offer high yield, mild conditions, and wide substrate scope. The reaction might involve the processes of
highly efficient and practical synthetic method for the preparation of pyrone diesters was established. The pyrone diester 3c can be prepared from readily available starting materials on a multihundred gram scale. The pyrone diester 3c can easily be converted to dolutegravir sodium (1). The synthetic route demonstrated herein provides an efficient and atom-economical synthetic method for preparing this
A Bench-Stable Vilsmeier Reagent for in situ Alcohol Activation: Synthetic Application in the Synthesis of 2-Amino-2-Thiazolines
作者:Michael Corbett、Seb Caille
DOI:10.1055/s-0036-1589086
日期:2017.12
A robust, chemoselective direct condensation/cyclization of thioureas and amino alcohols is described. Employing a bench-stable Vilsmeier reagent, methoxymethylene- N , N -dimethyliminium methyl sulfate, the selective in situ activation of alcohols is achieved with high efficiency and broad functional-group tolerance. The reversible interaction of the Vilsmeier reagent with substrate was key to the