Premium
A Straightforward Procedure for the [2+2+2] Cycloaddition of Enediynes
Author(s) -
Geny Anaïs,
Gaudrel Sophie,
Slowinski Franck,
Amatore Muriel,
Chouraqui Gaëlle,
Malacria Max,
Aubert Corinne,
Gandon Vincent
Publication year - 2009
Publication title -
advanced synthesis and catalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.541
H-Index - 155
eISSN - 1615-4169
pISSN - 1615-4150
DOI - 10.1002/adsc.200800646
Subject(s) - chemistry , cycloaddition , carbene , intramolecular force , phosphine , iodide , catalysis , cobalt , salt (chemistry) , combinatorial chemistry , manganese , ligand (biochemistry) , medicinal chemistry , stereochemistry , organic chemistry , biochemistry , receptor
Enediynes undergo intramolecular [2+2+2] cycloaddition in the presence of cobalt(II) iodide (CoI 2 ), manganese and an N‐heterocyclic carbene (IPr) generated in situ from the corresponding imidazolium salt and butyllithium (BuLi). Polycyclic cyclohexadienes are obtained selectively. This new method represents an interesting alternative to those employing air‐sensitive cyclopentadienylcobalt [CpCoL 2 (L=CO, C 2 H 4 )] catalysts. Moreover, the N‐heterocyclic carbene can be used catalytically, which is a significant improvement compared to the corresponding phosphine‐based system which requires an excess of ligand.