The 2,3-di
methylbutadiene co
mplex Tp
Me2Ir(CH
2=C(Me)C(Me)=CH
2) (
1) reacts with PhC
mages/entities/tbd1.gif">CPh, inC
6H
12 at 60
mages/entities/deg.gif">C, with coupling of the diene and the alkyne and for
mation of co
mpound
2a, which containsan elaborated bicyclic chelating ligand with alkyl and
mages/gifchars/eta.gif" BORDER=0 >
3-allyl functionalities. NCMe reacts reversiblywith
2a, giving rise to a
mixture of the iso
meric iridacyclopentenes
m060967xa10001">TpMe2m060967x00000">Ir(CH2C(Me)(CMe=CH2)C(Ph)=C(Ph))(NCMe) (
3) and
m060967xa10002">TpMe2m060967x00000">Ir(CH2C(Me)(cis-CPh=CHPh)C(Me)=CH)(NCMe) (
4). Co
mplex
2adeco
mposes in C
6H
12 at 80
mages/entities/deg.gif">C to give a co
mplex
mixture fro
m which an interesting substituted iridafulvene,
5, has been isolated by chro
matography. All these co
mpounds have been characterized by NMRspectroscopy and X-ray crystallography. Possible reaction
mechanis
ms for the for
mation of these speciesare discussed.