1.
Chemistry
; 25(41): 9624-9628, 2019 Jul 22.
Article
in English
| MEDLINE
| ID: mdl-31094025
ABSTRACT
A gold(I)-catalyzed cascade cyclization-alkynylation of allenoates using alkynyl bromide to generate ß-alkynyl-γ-butenolides was investigated. Whereas alkynyl iodides afforded significant amounts of the homo-coupling of two lactone units, alkynyl bromides led to a selective reaction, and a broad functional group tolerance was observed. Under the optimized reaction conditions, it was possible to directly synthesize a large range of ß-alkynyl-γ-butenolides in moderate to good yields without the need for any external oxidant.