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Palladium‐Catalyzed Regioselective 5‐ exo ‐ O ‐Cyclization/Oxidative Heck Cascades from o ‐Alkynylbenzamides and Electron‐Deficient Alkenes
Author(s) -
Madich Youssef,
Álvarez Rosana,
Aurrecoechea José M.
Publication year - 2014
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.201402709
Subject(s) - regioselectivity , chemistry , palladium , heck reaction , catalysis , oxidative coupling of methane , oxidative phosphorylation , oxidative addition , medicinal chemistry , organic chemistry , biochemistry
A Pd‐catalyzed 5‐ exo ‐selective oxycyclization/oxidative Heck coupling cascade is described, starting from readily available ortho ‐alkynylbenzamides and functionalized olefins. The key to a high regioselectivity in the cyclization step is the choice of catalyst and/or additives. Thus, Pd(OAc) 2 provides the desired 5‐ exo products predominantly, whereas with PdCl 2 or Pd(TFA) 2 , the corresponding 6‐ endo products prevail. The subsequent oxidative Heck‐type coupling takes place stereoselectively with the very predominant formation of E isomers, leading to an effective preparation of structurally diverse carbonyl‐substituted allylideneisobenzofuranimines.