Bi- and triheteronuclear complexes of uranium and group VI transition metals

The new heterobimetallic compounds Cp3U[OCM(CO)2Cp'] containing uranium and group VI transition metals are synthesized from Cp3UCl and Na[M(CO)3Cp'] or from Cp3UCH3 and H[M(CO)3Cp'] (M = Mo, W; Cp = C5H5; Cp' = C5H5 or C5Me5). In a same manner, the trimetallic Cp2U[OCMo(CO)2Cp]2 is obtained starting from Cp2U(NEt2)2 and H[Mo(CO)3Cp]. All these complexes exhibit low CO stretching frequencies characteristic of isocarbonyl linkages between uranium and Mo or W atoms. (author)