Gold-Catalyzed Highly Diastereoselective Synthesis of Functionalized 3,4-Disubstituted Butyrolactams<i>via</i>Phosphatyloxy or Carbonate Double Migrations
作者:Weibo Yang、Yang Yu、Tuo Zhang、Max M. Hansmann、Daniel Pflästerer、A. Stephen K. Hashmi
DOI:10.1002/adsc.201300158
日期:2013.7.8
A gold‐catalyzed highlydiastereoselectivesynthesis of functionalised 3,4‐disubstituted butyrolactams via phosphatyloxy or carbonatedoublemigrations is reported, which is proposed to proceed by a tandem 1,3‐phosphatyloxy or carbonatemigration and a “long‐range” 1,5‐phosphatyloxy or carbonatemigration, which overall corresponds to a formal 1,6‐migration.
joined by amides to olefines were prepared in situ from the related aldehydes with N-methylhydroxylamine. The nitrones added intramolecularly to the olefin, and the cycloadditions gave fused γ-lactams 6 stereoselectively. A stereocentre located in position α to the nitronic functionality 13 completely controls the stereochemical course of the intramolecular cycloadditions, which exclusively affords compound