Rhodium complexes with diacetyl monoxime ligands; crystal structure of [Rhcis- (C4H6NO)2cis-(PPh3)2]ClO4·CHCl3

Abstract The reaction of RhCl 3 ·3H 2 O with Hdamo and PPh 3 (Hdamo = diacetyl monoxime = C 4 H 7 NO), both in the absence ( 1 ) and in the presence of HClO 4 ( 2 ) afforded the complex Rh(damo)(PPh 3 ) 2 Cl 2 . The reaction of the acidic water/ethanolic solution of [Rh(H 2 O) 6 ] 3+ with Hdamo and PPh 3 ( 3 ) gave the mixture of the isomers of the compound [Rh(damo) 2 (PPh 3 ) 2 ]ClO 4 ( 3A and 3B ). A similar mixture of isomers was formed when [Rh(H 2 O) 6 ] 3+ reacted with H 2 dopn (H 2 dopn = 3,9-dimethyl-4,8-diazaundeca-3,8-diene-2,10-dione dioxime) and PPh 3 ( 4 ). Two isomers ( 4A = 3B ) and [Rh cis -(damo) 2 cis -(PPh 3 ) 2 ]ClO 4 ·CHCl 3 ( 4B ) have been isolated. All the compounds were characterized by elemental analysis NMR and IR spectroscopy. Single-crystal X-ray diffraction studies were carried out on the complex 4B . In this compound the coordination environment around rhodium(III) is pseudooctahedral composed of two cis -oxime nitrogen atoms [av. RhN = 2.031(3) A], two trans -oxime oxygen atoms [av. RhO = 2.026(2) A] and two cis -phosphine phosphorus atoms [av. RhP = 2.403(1) A].