Chemistry of mercaptopyridines and related ligands. Part 3. Novel examples of copper(II)–tertiary phosphine complexes stabilized by 1-hydroxypyridine-2-thione

Abstract

Reaction of 1-hydroxypyridine-2-thione (C₅H₅NOS) with copper(II) chloride dihydrate gave an insoluble dirty yellow compound of stoichiometry, [CuCl(C₅H₄NOS)]1 which is ESR active. Similar reaction with copper(II) bromide gave the ESR-active green compound [CuBr(C₅H₄NOS)(C₅H₅NOS)₂]7. Reactions of 1 and 7 with tertiary phosphines gave mixed-ligand complexes of stoichiometry CuX(C₅H₄NOS)L_n[n= 2 for PPh₃ and 1 for Ph₂P(CH₂)_mPPh₂, m= 1–4; X = Cl or Br], all of which are ESR active. The latter complexes represent the first novel examples of air- and moisture-stable copper(II)–tertiary phosphine complexes in which Cu^II is bonded to one halogen, one oxygen, one sulfur and two phosphorus atoms.