TRIMETHYLENEMETHANE COMPLEXES OF RUTHENIUM, OSMIUM AND RHODIUM VIA THE COMPOUND CH2=C(CH2SNME3)2

The compound CH2=C(CH2SnMe3)2 1 was readily made (61% yield) from K2(t mm) (tmm = trimethylenemethane) and SnMe3Cl. It serves as a new and ef ficient entry to tmm metal complexes. The arene complexes [{MCl2(arene )}2] (M = Ru or Os) reacted with 1 to give allylmetal complexes [MCI(C H2C(CH2SnMe3)CH2)(arene)] 2a-2e and sandwich-like compounds [M(tmm)(ar ene)] 3a-3e (M = Ru, arene = C6H6 a, C6Me6 b, or p-MeC6H4CHMe2 c; M = Os, arene = C6H6 d orp-MeC6H4CHMe2 e). The cymene complexes 3c and 39 can also be made using the combination CH2=C(CH2Cl)2-Mg-tetrahydrofura n as tmm source. Treatment of [{Rhl2(C5Me5)}2] with 1 produced [Rh(tmm )(C5Me5)] in high yield, and the carbonyl compounds [{MCl2(CO)3)2] (M = Ru or Os) afforded the tricarbonyl complexes [M(CO)3(tmm)] (M = Ru o r Os) in good yields. X-Ray crystal structure determinations have been made for 2a, 3a and [Ru(CO)3(tmm)]. The data for the last two show th e tmm ligand to be more firmly bonded in the arene complex.