ANTIMONY TRI BROMIDE

Chlorine reacts with antimony tri-2 thienyl to form the dichloride, M.pt. 229 C. (corr.) with decomposition. The corresponding di-bromide melts at 182 5 C. Treatment of these dihalidcs with potassium hydroxide transforms them into the oxide, M.pt. 217 C. (corr.) with decomposition. 

This reaction gives fair-to-good yields of monoorganotin tribromides and trichlorides when quaternary ammonium or phosphonium catalysts are used (149). Better yields are obtained with organic bromides and staimous bromide than with the chlorides. This reaction is also catalyzed by tri alkyl antimony compounds at 100—160°C, bromides are more reactive than chlorides in this preparation (150,151). a,C0-Dihaloalkanes also react in good yield giving CO-haloalkyltin trihaHdes when catalyzed by organoantimony compounds (152). 

Diethylgold bromide, 1666 Dimethylantimony chloride, 0896 Dimethylbismuth chloride, 0889 Ethylmagnesium iodide, 0855 Methylmagnesium iodide, 0445 Methylzinc iodide, 0446 ALKYLALUMINIUM HALIDES GRIGNARD REAGENTS TRI Al, KYI,ANTIMONY HALIDES... 

Other useful organometallic reagents for the preparation of tertiary stibines or related heterocyclic compounds are compounds of lithium, aluminum, tin, copper, zirconium, and other metals. " In most cases, these metal compounds are reacted with antimony chlorides or bromides. Good yields of tertiary stibines were, however, also obtained by the interaction (equation 3) of triaUcylaluminium reagents and tris(dimethylamino)stibine. ... 

Tri-n-butylstibine, (C4Hg)3Sb, boils at 131° C. at 12 mm., and has a density of 1 191 at 25° C. Tri-isobutylstihine, obtained from magnesium zsobutyl bromide and antimony trichloride, has B.pt. 135° C. at 31 mm., density 1 323 at 25° C. The first runnings in the distillation of the crude products contain j8e-dimethylhexane. The butylstibines possess a mixed alliaceous-butync odour. The wobutyl compound is distinctly yellow. 

Tri-n-butylstibine dibromide, (C4Hg)3SbBr2.—4 grams of finely powdered antimony and 10 c.c. of w-butyl bromide are heated togethei for thirty hours at 250° C. Extraction of the mass wdth ether and evaporation away of the solvent gives the bromide as an oil. It maj also be prepared by mixing ether solutions of tri-n-butylstibine and bromine. 

The halogen atom in dialkylaminophosphine chlorides or bromides can be replaced by fluorine on reaction with zinc of antimony fluoride (7.100). The same product is obtained from the tris derivative and boron trifluoride (7.101). 

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