precipitate is obtained. The analyses3 support the formula for bistrichlorostibine-triscarbonmonoxide iron, Fe( CO)r-(SbC13)*: Fe, 10.4 (calcd. 9.37); Sb, 39.3 (calcd. 40.83); C1, 34.4 (calcd. 35.70). The presence of carbon monoxide was shown qualitatively and a rough qualitative estimate of the gas evolved on thermal decomposition of the compound agrees with the other analyses. Like iron pentacarbonyl, the antimony trichloride complex is photosensitive, darkening on exposure to light, and consequently the reactions were carried out in absence of light.Both the nickel and iron complexes are amorphous powders, insoluble in organic solvents such as benzene, pentane, cyclohexane and carbon tetrachloride. Carbon disulfide reacts, liberating carbon monoxide and leaving dark colored residues. With alcohols and acetone, decomposition occurs, carbon monoxide is evolved, and solutions of divalent nickel and iron result, leaving a precipitate of antimony oxychloride. With water, dilute acids and alkalies, similar rapid reactions occur with loss of carbon monoxide, giving nickelous or ferrous solutions or hydroxides, antimony oxychloride or antimonate. The compounds are decomposed on heating to give carbon monoxide and, in the case of the iron compound, some metal carbonyl together with antimony trichloride. On treating the compounds with phosphorus trichloride, there is a vigorous reaction evolving carbon monoxide and it is possible that further substitution occurs; the color of the residue is darker but no analyses have been made.The great difference in properties between the antimony trichloride substitution compounds of nickel and those formed by the phosphorus halides may be due to the increasing inertness of the electron pair in the antimony halides compared with the phosphorus halides. Presumably there is also a lowered tendency to form T bonds with nickel which operate t o stabilize metal complexes. Efforts to identify further antimony trichloride substitution products were without success.Thanks are due to Mr. Thomas Vasilos for his assistance in part of the work, and to Professors John Kr. Irvine, Jr., and Charles D. Coryell for their valuable advice and discussions.