The reaction of cis-Cp*W(CO)(2)(MeCN)Me with (CNBu)-Bu-t gave a mixture of
the acetonitrile substitution products cis- and trans-Cp*W(CO)(2)((CNBu)-Bu
-t)Me and the CO insertion products cis- and trans-Cp*W(CO)((CNBu)-Bu-t)(2)
(COMe). The substitution was favored at room temperature, white the inserti
on was favored at low temperature.