The trichloro- and tribromo-acetato derivatives of copper() of general formula Cu2(CX3CO2)4(CX3CO2H)2 have been prepared by exchange reactions from Cu(CF3CO2)2 and CX3CO2H (X = Cl or Br) in a hydrocarbon solvent. The chloro derivative, which has also been obtained from CuO in the presence of CCl3CO2H/(CCl3CO)2O, has been characterized by variable-temperature magnetic measurements and by X-ray diffraction. The trifluoroacetato carbonyl derivative of copper(), Cu(CF3CO2)(CO), has been prepared: (a) by reaction of Cu2O with CF3CO2H/ (CF3CO)2O in the presence of CO; (b) by direct carbonylation of Cu(CF3CO2) in toluene or in the solid state; (c) by synproportionation of Cu(CF3CO2)2 and copper in the presence of CO in MeOH, DME, THF or toluene at room temperature. Solutions of Cu(CCl3CO2)(CO) have been obtained by the synproportionation of Cu2(CCl3CO2)4- (CCl3CO2H)2 and copper under a CO atmosphere in toluene. No carbonyl derivative was observed in solution with Cu2(CBr3CO2)4(CBr3CO2H)2 under similar conditions. On standing, hydrocarbon solutions of Cu(CCl3CO2)(CO) slowly gave CuCl(CO) and a mixed-valence, polynuclear carbonyl derivative of formula [Cu4(CCl3CO2)6(CHCl2CO2H)- (CO)2]n which has fully been characterized by variable temperature magnetic measurements and by X-ray diffraction.
Synproportionation Reactions between Copper(II) Trihaloacetates Cu(CX3COO)2 , X = F, Cl, Br, and Copper in the Presence of Carbon Monoxide
BELLI, DANIELA;CALDERAZZO, FAUSTO;PAMPALONI, GUIDO;
2000-01-01
Abstract
The trichloro- and tribromo-acetato derivatives of copper() of general formula Cu2(CX3CO2)4(CX3CO2H)2 have been prepared by exchange reactions from Cu(CF3CO2)2 and CX3CO2H (X = Cl or Br) in a hydrocarbon solvent. The chloro derivative, which has also been obtained from CuO in the presence of CCl3CO2H/(CCl3CO)2O, has been characterized by variable-temperature magnetic measurements and by X-ray diffraction. The trifluoroacetato carbonyl derivative of copper(), Cu(CF3CO2)(CO), has been prepared: (a) by reaction of Cu2O with CF3CO2H/ (CF3CO)2O in the presence of CO; (b) by direct carbonylation of Cu(CF3CO2) in toluene or in the solid state; (c) by synproportionation of Cu(CF3CO2)2 and copper in the presence of CO in MeOH, DME, THF or toluene at room temperature. Solutions of Cu(CCl3CO2)(CO) have been obtained by the synproportionation of Cu2(CCl3CO2)4- (CCl3CO2H)2 and copper under a CO atmosphere in toluene. No carbonyl derivative was observed in solution with Cu2(CBr3CO2)4(CBr3CO2H)2 under similar conditions. On standing, hydrocarbon solutions of Cu(CCl3CO2)(CO) slowly gave CuCl(CO) and a mixed-valence, polynuclear carbonyl derivative of formula [Cu4(CCl3CO2)6(CHCl2CO2H)- (CO)2]n which has fully been characterized by variable temperature magnetic measurements and by X-ray diffraction.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
