Stabilisation of alkynyl dithiocarboxylates at a ruthenium centre: X-ray crystal structures of [Ru(H)(CO)(S2CCCPh)(PPh3)2], [Ru(CO)(CPhCHPh)(S2CCCPh)(PPh3)2] and [Ru(CO)(CCMes)(S2CCCPh)(PPh3)2]

Solutions of the alkynyldithiocarboxylate anions RCC–CS2− (R=Mes, Ph, But), generated by treatment of the acetylides LiCCR with carbon disulfide, are sufficiently stable to allow reaction with haloruthenium(II) complexes. In this way, the complexes [Ru(H)(CO)(S2CCCR)(PPh3)2] and [Ru(CO)(CPhCHPh)(S2CCCR)(PPh3)2] (R=Mes, Ph, But) have been prepared and characterised. The vinyl complexes react with additional terminal alkynes R1CCH at room temperature to afford the acetylide complexes [Ru(CO)(CCR1)(S2CCCR)(PPh3)2]. The crystal structures of [Ru(H)(CO)(S2CCCPh)(PPh3)2], [Ru(CO)(CPhCHPh)(S2CCCPh)(PPh3)2] and [Ru(CO)(CCMes)(S2CCCPh)(PPh3)2] have been determined.