The signs of nuclear spin coupling constants in some trifluoromethyl derivatives of platinum and of gold

Abstract

The signs and magnitudes of ³J(³¹P ⋯¹H), ³J(³¹P ⋯¹⁹F), and other coupling constants have been determined by multiple-resonance methods in methyl and trifluromethyl derivatives of platinum(II), platinum (IV), gold(I), and gold (III). Whilst ³J(³¹P ⋯¹H) is more negative when the coupling path is trans than when it is cis, the converse is true of ³J(³¹P ⋯¹⁹F). The coupling fall into ranges which are sufficiently distinct to permit their diagonistic use, and their origin is discussed in terms of the bonding in the complexes.