Isolation of an extremely labile dihydrogen complex, Cr(CO)(sub 3)(PPr(super i)(sub 3))(sub 2)(H(sub 2)), containing the shortest ligated H-H bond

Different techniques help in the preparation of various transition metal dihydrogen complexes Cr(CO)(3)(PR3)(2) (eta (super 2)-H(2)) (R=cy, Pr(super i)). X-ray crystallography and several other techniques are used for the characterization of these complexes. Cr(CO)(3) (PPr(3) (super i)(2) CH(2)) is the most unstable separable H(2) complex which has the shortest ligated H-H bond.