Synthesis, characterization and chemistry of some long chain alkoxycarbonyl manganese pentacarbonyl complexes [Mn(CO)5{C(O)OR}] (where R = n-C7H15 to n-C10H21, n-C12H25, n-C14H29, and n-C16H33)

The long chain alkoxycarbonyl complexes, [Mn(CO)(5){C(O)OR}], where R = CH2R', and R = n-C7H15 to n-C10H21, n-C12H25 and n-C16H33, have been synthesized by the reactions of the acyl complexes [Mn(CO)(5){C(O)R'}], where R' = n-C6H13 to n-C9H19, n-C11H23 and n-C15H31, with synthesis gas in hexane. In addition, the complexes [Mn(CO)(5){C(O)OR}] (R = n-C9H19 and n-C14H29) have been synthesized by the reactions of the alkyl complexes [Mn(CO)(5)R "], where R " = n-C8H17 and n-C13H27, with synthesis gas in hexane. These new alkoxycarbonyl complexes have been fully characterized by elemental analysis, melting point, IR, H-1-NMR, C-13-NMR and mass spectroscopy. The thermal behaviour of these complexes has been investigated by differential scanning calorimetry and thermal gravimetry analysis. The reaction of the acyl complex [Mn(CO)(5){C(O)C11H23}] with synthesis gas in THF gave [Mn-2(CO)(10)] (95%) and the alcohol n-C12H25OH (92%). The reaction of the alkoxycarbonyl complex [Mn(CO)(5){C(O)OC12H25}] with synthesis gas in hexane at 85 degrees C gave the formate HCO2C12H25 (66%), the alcohol n-C12H25OH (33%) and [Mn-2(CO)(10)] (96%). The same reaction as above in THF yielded the formate HCO2C12H25 (12%), the alcohol n-C12H25OH (46%) and the ester CH3(CH2)(3)CO2C12H25 (43%) as well as [Mn-2(CO)(10)] (63%). These studies show that the reactions of the acyl complexes [Mn(CO)(5){C(O)R'}], the alkyl complexes [Mn(CO)(5)R "] and the alkoxycarbonyl complexes [Mn(CO)(5){C(O)OR}] with synthesis gas are both solvent and temperature dependent. (C) 1998 Elsevier Science S.A. All rights reserved.