Abstract: | Abstract Treatment of trans-Mo(N2)2(dpe)(dpm)] (dpe = Ph2PCH2CH2PPh2, dpm = Ph2PCH2PPh2) or trans-Mo(N2)2(dpe)(dpp)] (dpp = Ph2PCH2CH2CH2PPh2) with excess DMF in benzene at reflux under Ar resulted in the formation of trans-Mo(CO)(DMF)(dpe)(dpm)] or trans-Mo(CO)(DMF)(dpe)(dpp)]. X-ray structural analysis of trans-Mo(CO)(DMF)(dpe)2] was performed using single crystals isolated as the minor product from the reaction mixture of trans-Mo(N2)2(dpe)(dpp)] and DMF. Crystal data: C56H55O2NP4Mo, monoclinic, space group P21, a = 11.145(4), b = 23.425(5), c = 10.516(3) Å, β = 117.17(2)° V = 2442.6(13) Å3, D calcd = 1.35 g/cm3 for Z = 2. This disclosed the relatively long C O bond distance of the carbonyl ligand and the significantly short C=O bond length in the DMF ligand. When recrystallized from benzene/hexane under N2, trans-Mo(CO)(DMF)(dpe)(dpm)] was converted into trans-Mo(CO)(N2)(dpe)(dpm)]. |