Crystal and molecular structures of 2-bis(methyldiphenylphosphine)- and of 2-bis(triphenylphosphine)-4,4,6,6-tetrakis(trifluoromethyl)-1,3,5,2-trioxaplatinan: adducts of hexafluoroacetone with peroxobis(methyldiphenylphosphine)platinum(II) and with peroxobis(triphenylphosphine)platinum(II)

Abstract

Crystals of (MePh₂P)₂·[graphic omitted] (I) are orthorhombic, space group Pca2₁, with Z= 4 in a unit cell of dimensions: a= 22.040(20), b= 9.683(6), c= 16.235(3)Å; the structure was elucidated by heavy-atom methods from 2 611 diffracted intensities measured by diffractometer, and refined to R 0.085. Crystals of (Ph₃P)₂·[graphic omitted] (II) are triclinic, a= 14.559(9), b= 12.287(6), c= 12.819(3)Å, α= 107.62(3), β= 84.57(4), γ= 105.74(4)°, and the structure was similarly elucidated from 5 296 intensities measured by diffractometer; R 0.068. In (I) and (II) the platinum, which is in an approximately square-planar environment, forms part of a six-membered condensed hexafluoroacetone ring which is markedly non-planar. The O–C(CF₃)₂ bonds from the oxygen atoms adjacent to the metal in this ring are notably short [1.323(14)Å]. The line joining the Pt atom to the furthermost ring oxygen atom is an approximate two-fold axis for the ring.