Premium
Cobalt‐Catalyzed Intermolecular [2+2] Cycloaddition between Alkynes and Allenes
Author(s) -
Ding Wei,
Yoshikai Naohiko
Publication year - 2019
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201813283
Subject(s) - allene , alkyne , regioselectivity , chemistry , cycloaddition , catalysis , yield (engineering) , intermolecular force , cobalt , derivative (finance) , medicinal chemistry , photochemistry , organic chemistry , molecule , economics , financial economics , metallurgy , materials science
Abstract An intermolecular [2+2] cycloaddition reaction between an alkyne and an allene is reported. In the presence of a cobalt(I)/diphosphine catalyst, a near equimolar mixture of the alkyne and allene is converted into a 3‐alkylidenecyclobutene derivative in good yield with high regioselectivity. The reaction tolerates a variety of internal alkynes and mono‐ or disubstituted allenes bearing various functional groups. The reaction is proposed to involve regioselective oxidative cyclization of the alkyne and allene to form a 4‐alkylidenecobaltacyclopentene intermediate, with subsequent C−C reductive elimination.