(Ph3P)2Rh(SPCy2): A complex containing a side-on bonded η2-secondary phosphine sulfide anion

Abstract

The reaction of Cp2Zr(SPCy2)2 with either (Ph3P)3RhH(CO) or (Ph3P)4RhH led not to the expected heterobimetallic species but rather to a novel Rh species (Ph3P)2Rh(SPCy2), 4. The 31P{1H} NMR spectrum of this complex is an ABCX pattern. The molecular geometry of 4 was confirmed by a crystallographic study. Compound 4 crystallizes in the space group P21/c with a = 10.912(1) Å, b = 12.335(2) Å, c = 32.346(7) Å, β = 96.17(1)°, V = 4328(1) Å3 and Z = 4, The coordination sphere about Rh in 4 is pseudo-square planar, containing three phosphorus and a sulfur atom from the two coordinated phosphines and a side-on bonded SPCy2 moiety. This structural study confirms that the secondary phosphine chalcogenide is bonded to Rh in an η2 fashion. The complex 4 is only the fourth example in which this mode of binding has been crystallographically confirmed and is the first such species to involve one of the Pt group metals.