Chemistry Reference
In-Depth Information
8C
ASYMMETRIC CARBOMETALLATION
AND CARBOCYCLIZATIONS
IWAO OJIMA , JOSEPH J. KALOKO , STEPHEN J. CHATERPAUL ,
YU - HAN GARY TENG , AND CHI - FENG LIN
Department of Chemistry, Stony Brook University, Stony Brook, NY
8C.1. INTRODUCTION
Organometallics add to carbon-carbon multiple bonds forming a new organometallic
species (Eq. 8C.1), where the new carbon-metal bond can be further modifi ed affording
new carbon-carbon bonds (Eq. 8C.2) [1]. These reactions are classifi ed as “ carbometal-
lation reactions.”
R
Mm
RMLn
R
(8C.1)
Mm
E
+
R
2
R
2
R
1
MLn
R
2
R
1
MLn
R
1
E
(8C.2)
A
B
C
D
The term carbometallation refers primarily to a relationship between reactants and
products and has no necessary mechanistic implications about the reaction system. Many
of the so-called carbometallation reactions are in fact mechanistically independent of
