Synthesis and characterization of copper(I) and copper(II) coordination compounds containing 4-acylpyrazolon-5-ato ligands. Crystal structure of [(4-trifluoroacetyl-1-phenyl-3-methylpyrazolon-5-ato)bis(triphenylphosphine)copper(I)]

New [(Q)(2)Cu-II] and [(Q)(2)(L)Cu-II] derivatives (in general QH is 1-R-3-methyl-4-R'-pyrazol-5-one; in particular: Q'H: R = C6H5, R' = C6H5(C=O); Q '' H: R = C6H5, R' = CH3(C=O); Q(F)H: R = C6H5, R' = CF3(C=O); Q(Cl)H: R = C6H5, R' = CCl3 (C=O); Q(Br)H: R = C6H5, R' = p-BrC6H4(C=O); Q(A)H: R = C6H5, R' = p-CH3O-C6H4(C=O), Q(E)H: R = C6H5, R' = C6H13(C=O); Q(M)H: R = CH3, R' = C6H5(C=O); Q(D)H: R = CH3, R = CH3(C=O); Q(B)H: R = C6H5, R' = C6H5(C=N(p-CH3C6H4)); L = 2,2'-bipyridine or 1,10-phenanthroline) were synthesized and characterized through analytical and spectral techniques. When (Q)(2)Cu-II interacted with an excess of PPh(3), reduction to copper(I) was observed and (Q)Cu-I(PPh(3))(2) complexes were synthesized. The complex (Q(F))Cu-I(PPh(3))(2) was characterized by single crystal X-ray diffraction. The coordination environment of copper is a distorted tetrahedron : the P-Cu-P angle is 127.8(1)degrees and the ligand ''bite'' O-Cu-O angle is 87.8(3)degrees; the Cu-O bond distances are 2.075(7) and 2.109(7) Angstrom, while Cu-P are 2.246(3) and 2.254(3) Angstrom. Copyright (C) 1996 Elsevier Science Ltd