Reactivity of the unsaturated manganese dihydrides (L2 = Ph2PCH2PPh2 or (EtO)2POP(OEt)2) towards small molecules

Article abstract of DOI:10.1016/0022-328X(95)05944-K

The unsaturated dihydrides (L2 = Ph2PCH2PPh2, dppm, 1 or (EtO)2POP(OEt)2, tedip, 2) react with carbon dioxide or formic acid to yield a mixture containing the hydridoformate isomers 2-O2CH)(CO)6(μ-L2)> (L2 = dppm, 3a; tedip, 3b) and 1-OC(O)H)(CO)6(μ-L2)> (L2 = dppm, 4a; tedip, 4b) in equilibrium.Our previous characterization of the second complex as 2-O2CCH3)(CO)6(μ-L2)> was erroneous.In contrast, reaction of 1 with CH3COOH yields the acetate complex 2-O2CCH3)(CO)6(μ-dppm)> (3c) as the sole product.Dihydride 1 also reacts with organic Broensted acids such as 4-nitrophenol, tert-butylmercaptan and 4-toluenethiol yielding the corresponding hydridoalkoxide (5a), or hydridothiolates (R = C(CH3)3, 6a; 4-C6H4-CH3, 6b) respectively.Related hydridoalkoxides, (L2 = dppm; R = CH2CH3, 5c; CH2-4-C6H4-CH3, 5d; CH(CH3)2, 5f, L2 = tedip, R = CH2C6H5, 5e; CH(CH3)2, 5g; CH(CH3)CH2CH3, 5h), can be obtained in good yield by treatment of 1 or 2 with the appropriate aldehydes or ketones at room temperature. - Keywords: Manganese; Dihydrides; X-ray structure