Rh6(CO)16 was first prepared by Heiber in 1943 by carbonylation of RhCl3·3H2O at 80-230 °C and 200 atm carbon monoxide with silver or copper as a halide acceptor. It was incorrectly formulated as Rh4(CO)11. Subsequently, the carbonylation of a mixture of anhydrous rhodium trichloride and iron pentacarbonyl was shown to give good yields of Rh6(CO)16. Other compounds of rhodium are also effective precursors such as Rh2Cl2(CO)4 and rhodium(II) acetate:
3 Rh2(O2CCH3)4 + 22 CO + 6 H2O → Rh6(CO)16 + 6 CO2 + 12 CH3CO2H
^ abBooth, B.L.; Else, M.J.; Fields, R.; Goldwhite, H.; Haszeldine, R.N. (1968). "Metal carbonyl chemistry IV. The preparation of cobalt and rhodium carbonyls by reductive carbonylation with pentacarbonyliron". Journal of Organometallic Chemistry14 (2): 417. doi:10.1016/S0022-328X(00)87682-2.