SYNTHESIS AND CHARACTERIZATION OF COPPER(I) AND COPPER(II) COORDINATION-COMPOUNDS CONTAINING 4-ACYLPYRAZOLON-5-ATO LIGANDS - CRYSTAL-STRUCTURE OF LPYRAZOLON-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' = C6H 5(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' = C6 H13(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 analyti cal and spectral techniques. When (Q)(2)Cu-II interacted with an exces s 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 ch aracterized by single crystal X-ray diffraction. The coordination envi ronment 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; t he 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 Scienc e Ltd