Benzene migration in an osmium cluster: the formation of Os 3 (CO) 7 (η 6 -C 6 H 6 )(µ 3 : η 1 : η 2 : η 1 -C 2 Me 2 ) from Os 3 (CO) 9 (µ 3 : η 2 : η 2 : η 2 -C 6 H 6 ). The crystal structure of Os 3 (CO) 7 (η 6 -C 6 H 6 )(µ 3 : η 1 : η 2 : η 1 -C 2 Me 2 )

The activated cluster [Os3(CO)7(C2H4)(µ3 : η2 : η2 : η2-C6H6)(MeCN)] reacts with alkynes RC2R′(R = R′= H, Ph or Me; R = H, R′= Ph; R = ME, R′= Et), to produce the new clusters [OS3(CO)7(η6-C6H6)(µ3 : η1 : η2 : η1-RC2R′)] in which the benzene is bonded to a single metal atom as shown by a single crystal X-ray structure determination of the C2Me2 derivative.