Reactivity of rhenium(I) pseudo-allyl complexes with heterocumulenes. Part 2. Insertion reactions. Crystal structures of the thiazolyl-thioureido and -dithiocarbamato complexes [Re(CO)2(PPh3)2{SC(NPh)NMe(C3H2NS)}]·CH2Cl2 and [Re(CO)2(PPh3)2{S2CNMe(C3H2NS)]·CH2Cl2(C3H2NS = thiazol-2-yl)

Abstract

The compound [Re(CO)₂(PPh₃)₂(mat)][mat = anion of 2-(methylamino)thiazole] reacts under anhydrous conditions with an excess of PhNCS or CS₂ to give the thioureido rhenium(I) derivative [Re(CO)₂(PPh₃)₂{SC(NPh)NMe(C₃H₂NS)}](1) and the dithiocarbamate rhenium(I) complex [Re(CO)₂(PPh₃)₂{S₂CNMe(C₃H₂NS)}](2) respectively (C₃H₂NS = thiazol-2-yl). They are obtained by formal insertion of the heterocumulene into the Re–N bond. Compound (1) is triclinic, space group P, with a= 15.058(6), b= 14.305(6), c= 12.371(6)Å, α= 108.51(3), β= 75.16(3), γ= 104.91(3)° and Z= 2. The structure was refined to the final conventional R of 0.055. The rhenium atom is six-co-ordinate distorted octahedral. The organic ligand chelates through the nitrogen atom of the thiazole ring and the sulphur atom of the PhNCS moiety, and together with the metal forms a non-planar six-membered ring. Selected bond distances are: Re–P 2.436 (mean), Re–C 1.89 (mean), Re–N 2.20(1), Re–S 2.471(3)Å. Compound (2) is monoclinic, space group P2₁/n, with a= 21.305(5), b= 17.873(5), c= 11.455(7)Å, β= 97.81(3)°, and Z= 4. The structure was refined to the conventional R of 0.052. The rhenium atom is six-co-ordinate distorted octahedral. The organic ligand chelates through the two sulphur atoms of the CS₂ moiety and together with the metal forms a planar four-membered ring. Selected bond distances are: Re-P 2.431 (mean), Re–S 2.513 (mean), and Re–C 1.88 Å(mean).