Highly selective hydrogenation of CO(2) into C(2+) alcohols by homogeneous catalysis

The hydrogenation of CO(2) to produce alcohols with two or more carbons (C(2+) alcohols) is of great importance, but is challenging. In this work, we found that a Ru(3)(CO)(12)/Rh(2)(CO)(4)Cl(2)–LiI system could catalyze the reaction effectively in 1,3-dimethyl-2-imidazolidinone (DMI) under mild conditions. Methanol, ethanol, propanol, 2-methyl propanol, butanol, and 2-methyl butanol were produced in the homogeneous catalytic reaction. The C(2+) alcohols could be generated at 160 °C, which is the lowest temperature reported so far for producing C(2+) alcohols via CO(2) hydrogenation. The selectivity for the C(2+) alcohols could be as high as 96.4% at the optimized conditions, which is higher than those reported in the literature. In addition, the catalytic system could be easily recycled. The route of the reaction for forming the C(2+) alcohols was discussed on the basis of control experiments.