REACTIVITY OF CARBONYL-STABILIZED YLIDES WITH ZEISES SALT - SYNTHESIS, CHARACTERIZATION OF MONO-YLIDIC AND BIS-YLIDIC PT(II) DERIVATIVES AND X-RAY CRYSTAL-STRUCTURE OF THE CL2[C(H)COCH3(PPH(2)-O-C6H4)])[PPH(3)CH(2)COCH(3)] COMPLEX

Phosphorus and arsenic keto-stabilized ylides (APPY, CMPPY, BPPY, BCyP Y-OMe, APAsY, CMPAsY, BPAsY) react with Zeise's salt to give the corre sponding monosubstituted Pt(II) complexes trans-[PtCl2(eta(2)-C2H4)(yl ide)] (1-7). The bis-ylide complexes trans-[PtCl2(ylide)(2)] (8-12) an d trans-[PtCl2(ylide)(ylide')] (13-17) can be prepared by reaction of 1-7 with the corresponding ylides. Upon heating complex 8 trans-{PtCl2 [C(H)(PPh(3))COCH3](2)} in THF a cyclization reaction occurred to give Cl2[C(H)COCH3(PPh(2)-o-C6H4)]}[Ph(3)PCH(2)COCH(3)] (18). The molecula r structure of compound 18 was determined by X-ray diffraction. The mo lecule consists of a metallic anion and a phosphonium counterion. Comp ound 18 crystallizes in the monoclinic space group P2(1)/c with unit c ell parameters a=13.855(3), b=14.242(3), c=20.173(4) Angstrom, beta=10 9.31(5)degrees, Z=4.