Boron trichloride reaction with hydrogen

Boron trichloride, reaction with 2-aminobiphenyl, 46, 66 Boron trifluoride, in preparation of ni-tronium tetrafluoroborate, 47, 56 with hydrogen fluoride in isomerization of /-cymene to tM-cymene, 47, 41... 

Fatty acid analysis of a fat is nowadays a relatively routine analytical operation. After methylation of the fat using reaction with boron trifluoride/methanol, boron trichloride/methanol, methanolic hydrogen chloride solution, diazomethane or, if free fatty acids are not present, alkaline catalysts such as sodium methoxide/methanol, the prepared methyl esters are then analysed by GC on a polar column such as CpSil 88, BPX70 or SP2340. The high polarity of the column is necessary to separate the saturated and unsaturated fatty acids fully. The fatty acid composition of a milk fat sample is thus relatively easily obtained, and was therefore one of the first techniques investigated for authentication purposes. 

The deposition of boron phosphide by CVD was carried out in a gas flow system by the thermal decomposition of diborane-phosphine mixtures in a hydrogen atmosphere and the thermal reduction of boron tribromide-phosphorus trichloride mixtures with hydrogen (37). The hydrides are thermodynamically unstable at room temperature and decompose rapidly at above 500°C, which tends to promote homogeneous nucleation by pyrolysis in the gas phase. The halides are thermally more stable than the hydrides, and higher substrate temperatures may be used in the thermal reduction process with essentially no gas-phase reactions. At high substrate temperatures, a phosphorus pressure equal to or greater than the vapor pressure of boron phosphide must be present over the substrate surface to maintain the stoichiometry of the deposit. 

Hafnium Boride. Hafnium diboride [12007-23-7] HfB2, is a gray crystalline soHd. It is usually prepared by the reaction of hafnium oxide with carbon and either boron oxide or boron carbide, but it can also be prepared from mixtures of hafnium tetrachloride, boron trichloride, and hydrogen above 2000°C, or by direct synthesis from the elements. Hafnium diboride is attacked by hydrofluoric acid but is resistant to nearly all other reagents at room temperature. Hafnium dodecaboride [32342-52-2] has been prepared by direct synthesis from the elements (56). 

The above reaction is utilized in large-scale industrial production of methanol. Reaction with boron trichloride over a hot tungsten or tantalum filament yields boron and hydrogen chloride ... 

The reaction of titanium tetrachloride with boron trichloride and hydrogen to give solid titanium diboride is an example of the second type of CVD reaction ... 

Chlorodifluoroamine has been prepared by reaction of difluoro-amine with boron trichloride,1 phosgene (carbonyl chloride),2 or hydrogen chloride 2 treating a mixture of sodium azide and sodium chloride with fluorine 3 reaction of chlorine trifluoride with ammonium fluoride 4 reaction of chlorine with diflu oro-amine in the presence of potassium fluoride 5 and photolysis of tetrafluorohydrazine and sulfinyl chloride (thionyl chloride).6... 

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