1,2-Bis{bis[4-(trifluoromethyl)phenyl]phosphino}ethane

Abstract

Crystals of the title compound, C30H20F12P2 or R2PCH2CH2PR2 (R = 4-C6H4CF3), were inadvertently prepared while attempting to recrystallize a crude sample of trans-Re(Cl)(N2)(R2PCH2CH2PR2)2 from diethyl ether. The molecule lies on a center of inversion. One of the rings lies approximately in the P—C—C—P plane; the dihedral angle is 174.53°.The other ring is not quite perpendicular; the dihedral angle is 71.1°. The compound is isostructural with the R = Ph, 4-C6H4CH3 and 4-C6H4CH2CH3 analogues. It is well known that the basicity of phosphines and diphosphines can be altered by changing the electron-donating ability of R; however, the structural parameters for the title compound do not significantly differ from those of the aforementioned substituted-phenyl compounds.