The complexes [
WCl(CO)
2(
3-CH
2C(COX)C=CH
2)L
2] (X = Cl; L
2 = 2,2'-bipyridyl, 1,10-phenanthroline) (
1) containing a 2-substituted butadienyl lig
and were isolated from reactionsof Ph
4P[WCl(CO)
3L
2]
and excess 1,4-dichlorobut-2-yne in chlorinated solvents. Spectroscopicevidence supports analogous reactions for the chromium analogue. Addition of
1 to alcohol,amine, or thiol (HX) gave good yields of the related ester (X = OMe), amide (X = NEt
2), orthiolate (X = SBu
n) complexes, respectively. Mechanisms
and supporting evidence for theformation of
1 and the ester complex are proposed
and discussed. Some differences inreactivity of Ph
4P[MCl(CO)
3L
2]
with 1,4-dichlorobut-2-yne in methanol are reported for M= Mo
and M = W. The structure of [WCl(CO)
2(
3-CH
2C(COSBu
n)C=CH
2)(1,10-phenanthroline)]
was confirmed by single-crystal X-ray diffraction analysis.