STABILITY IN SOLUTION OF (CHLOROMETHYL)PALLADIUM(II) COMPLEXES - X-RAY STRUCTURES OF TRANS-BIS(TRIPHENYLPHOSPHINE)CHLORO(CHLOROMETHYL)PALLADIUM(II) AND -PLATINUM(II) AND COMPARISON OF THE RELATIVE STABILITIES OF ANALOGOUS PALLADIUM AND PLATINUM CHLOR

摘要

The stabilities to storage in CDCl3 solution (both in the absence and presence of air) of a series of chloro(chloromethyl)palladium(II) complexes of neutral olefinic, sulfide, amine, and phosphine ligands have been investigated. The decomposition rates and types of products formed depend upon the nature of the ligands. Three types of reactions involving the CH2Cl moiety were found: (i) oxidation to formaldehyde, (ii) formation of ylide complexes, and (iii) coupling to ethene and propene. Since the phosphine complex trans-[(Ph(3)P)(2)Pd(CH2Cl)Cl] (9) proved to be much more stable to storage in solution than its Pt analogue (17), we have compared their X-ray structures. Crystals of 9 (C37H32Cl2P2Pd) are monoclinic, space group P2(1), with 4 molecules in a cell of dimensions a = 12.361(5) Angstrom, b = 22.714(4) Angstrom, c = 12.328(4) Angstrom, and beta = 111.36(3)degrees. Compound 17 (C37H32Cl2P2Pt) is isomorphous with 9, with cell dimensions a = 12.332(2) Angstrom, b = 22.784(3) Angstrom, c = 12.344(1) Angstrom, and beta = 111.32(1)degrees. Both structures were refined by full-matrix least-squares calculations on F; the final R values are 0.024 for both structures (for 5763 and 6621 reflections, respectively). The possibility that differences in the M-CH2-Cl distances in 9 and 17 may reflect their relative tendencies to form carbene complexes by heterolysis of the CH2-Cl bond is discussed. [References: 46]