vic-Dichlorodiphosphapropenes – Synthesis and Coordination Ability

New substituted 2,3-dichloro-1-λ3σ2-P,3-λ3σ3-P-diphosphapropenes Mes*P=C(Cl)-P(Cl)tBu (1) (Mes* = 2,4,6-tri-tert-butylphenyl) and the oxidation compounds Mes*P=C(Cl)–P(=E)(Cl)R [R = tBu, E = S (2), O (3); R = Mes, E = O (4)] are reported. From the reaction of 2 with W(CO)5(thf) the chelate compound W(CO)4[Mes*P=C(Cl)–P(S)(Cl)tBu] (5) was obtained. Reaction of 1 or 2 with PdCl2(cod) led to PdCl2[cyMes*PC(H)(Cl)–P(Cl)tBu] (cyMes*P = 5,7-di-tert-butyl-3,3-dimethyl-1-phosphaindane) (6) or PdCl2[cyMes*PC(H)(Cl)–P(S)(Cl)tBu] (7), in which the coordination to the Pd atoms is accompanied by intramolecular addition of CH(tBu) of Mes* to the P=C bond of the dichlorodiphosphapropene. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)