Alcohol homologation

A process for the reaction of an alcohol of the general formula R'OH, wherein R' is a monovalent hydrocarbyl (i) alkyl group having from 1 to 20 carbon atoms, (ii) alkenyl group having from 2 to 20 carbon atoms, or (iii) aralkyl group in which the aryl moiety is phenyl or naphthyl and the alkyl moiety has from 1 to 10 carbon atoms, with synthesis gas to selectively produce realizable alcohol;

• said process conducted at a temperature of from 50.degree. C. to 250.degree. C., a pressure of from 100 psig to 10,000 psig, wherein said synthesis gas has a H.sub.2 :CO mole ratio of 1:10 to 10:1, in contact with a rhodium-based catalyst system containing rhodium atom, ruthenium atom, iodine atom and a bis(diorganophosphino)alkane ligand of the general formula R.sub.2 PXPR.sub.2, wherein X is a linear or branched alkyl, alkenyl or cyclic divalent bridge connecting the two P atoms, the terminal bonds of said bridge being from 1 to 10 carbon atoms apart and R is (i) a hydrogen atom with the proviso not more than one hydrogen atom is attached to a P atom, or (ii) an alkyl group having from 1 to 20 carbon atoms or (iii) an aryl, aralkyl or alkaryl group having 6 to 20 carbon atoms in the aryl moiety and from 1 to 10 carbon atoms in the alkyl-moiety;
• wherein the mole ratio of rhodium to alkanol is from 1:25 to 1:2500, the mole ratio of rhodium to ruthenium is from 1:10 to 10:1, the mole ratio of rhodium to iodine is from 1:500 to 500:1 and the mole ratio of rhodium to R.sub.2 PXPR.sub.2 is from 1:100 to 100:1.