in toluene under N2; addn. of α-imino ketone to stirred suspn. of Fe2(CO)9 in toluene, stirring for 14 h at room temp.; bubbling air through soln. for 5 min, evapn., column chromy. (SiO2, pentane for Fe3(CO)12, 6:2 pentane/Et2O for Fe2(CO)6 complex), crystn. frompentane at -60°C (Fe2(CO)6 complex);

4 A molecular sieve in diethyl ether T=30°C; 72 h;