Synthesis, Structure, and Photoluminescent Properties of Copper(I) Complexes with N-(diphenylphosphino)-4-Phenylpyrimidineamine

Abstract

Complexes of copper(I) iodide, bromide, and chloride with N-(diphenylphosphino)-4-phenylpyrimidineamine (L) are synthesized. The [Cu₂L₂I₂] (I), [Cu₂L₂I₂]·2.3MeCN (II), [Cu₂L₂Br₂] ·1.5MeCN·0.5CH₂Cl₂ (III), and CuLCl (IV) complexes are prepared by reactions of the corresponding copper(I) salts and L in organic solvents in the 1:1 molar ratio. It is shown by XRD that II and III have a binuclear molecular structure; the L molecule is coordinated to copper atoms in a bidentate cyclic mode via P and N1 atoms of the pyrimidine ring; the distorted tetrahedral environment of Cu atoms is supplemented by halide ions; the coordination polyhedron is CuNPI₂ (II) and CuNPBr₂ (III). The structure of II has two crystallographically independent molecules containing a {Cu₂I₂} fragment in rhombus and butterfly conformations, respectively. In the molecule of II, all {Cu₂Br₂} fragments have a planar rhombic structure. Solid-state photoluminescent properties of L and I, III, IV complexes are studied. The I, III, IV complexes demonstrate single-band red emission with a microsecond lifetime (λ_exc = 400 nm) at 635 nm, 625 nm, and 640 nm, respectively. The L compound exhibits solid-state fluorescence with two emission bands at 400 nm and 480 nm.