The reaction of Cr(CO)(6) with arylhimachalene yields the title aryl organo
metallic compound, tricarbonyl[(1,2,3,4,4a,9a-eta)-(7S)-3,5,5,9-tetramethyl
-6,7,8,9-tetrahydro-5H-benzocycloheptene]chromium(0), [Cr(C15H22)(CO)(3)],
with the hydrocarbon linked to a Cr(CO)(3) tripod group. The crystal struct
ure of one of the stereoisomeric products, i.e. that with the tripod anti t
o the methyl group on the asymmetric carbon, is presented here.