Syntheses and crystal structures of group 6 metal complexes containing allyl and cyanotrihydroborate groups

Compounds M(η3-C3H5)(CO)2(NCCH3)2(NCBH3), and [M(η3-C3H5)(CO)2(NCBH3)3]2− (M = Mo, W) were prepared and characterized. The M-N interaction was found and the spectroscopic data suggested most of the negative charge of the complexes is localized on the BH3.