The structure determination of the title complex, [Ir(C5H7OS)(CH3)(I)(
C8H12)], revealed that the oxidative addition of iodomethane to (eta(4
) 1,5-cyclooctadiene)(thioacetylacetonato)iridium(I) results in the fo
rmation of the trans isomer. The deviation of the I-Ir-CH3 angle [156.
1(3)degrees] from linearity is attributed to steric repulsion between
the CH3 group or I atom and the olefinic H atoms.