Boron trifluoride crystal structure

Mootz, D. and Steffen, M. (1980) Boron trifluoride crystal structure of a metastable phase. Angew. Chem., Int. Ed. Engl, 92, 483-484. 

It is especially important to investigate the molecular structure of coordination compounds in the vapor phase because the relatively weak coordination interactions may be considerably influenced by intermolecular interactions in solutions and especially in crystals. It has been shown that the geometrical variations can be correlated with other properties of the molecular complexes ). In particular the structural changes in the F3B N(CH3)3 and CI3B N(CH3)3 molecules ) relative to the respective monomeric species unambiguously indicated boron trichloride to be a stronger acceptor than boron trifluoride. Data on the geometry and force field have also been correlated ). 

Tris[3-tert-butyl-4-(hydroxybenzyl)]mesitylene (III) was synthesized starting from 2-fert-butyl-6-chlorophenol, which in turn was prepared by the method of Kolka et al. (10). The 2-ferf-Butyl-6-chlorophe-nol was alkylated with a1,a3,a5-(trihydroxyhexamethyl)benzene (Aldrich) with the use of boron trifluoride etherate catalyst (II). A mixture of I and II was obtained, separated by fractional crystallization from methyl-cyclohexane. The structures of the two products were assigned on the... 

The products reported as obtained from (l-alkyl-3-arylaziridin-2-yl)-arylmethanone tosylhydrazones 271 <1996H(43)305> and semicarbazones 272 <1994NKK893>, respectively, by treatment with boron trifluoride etherate are not tetrahydro-l,2,3-triazines 269 and 270 but 2,3,4,5-tetrahydro-l,2,4-triazines 273 and 274 (Equation 119), as proven by a single crystal X-ray structural analysis for 273 (R = f-C6Hn, Ar = Ar = Ph)... 

Thermolysis of (55) yields 1,2X, -azaphosphete (56), which undergoes reaction with boron trifluoride or methyl iodide with retention of the ring, while ring expansion reactions occur with isocyanates, isothiocyanates and acetylenedicarboxylates, and ring opening processes occur with water, carbon disulfide and penta-fluorobenzonitrile. An X-ray crystal structure is available for (56, R = NPr2 ) (94JA8087). 

Table 5.9 lists the structures of polychloroprenes that form by free-radical polymerization at different temperatures. Chloroprene polymerizes by cationic polymerization with the aid of Lewis acids in chlorinated solvents. When aluminum chloride is used in a mixture of ethyl chloride-methylene chloride solvent mixture at -80 °C, the polymer has 50% 1,4 units. If it is polymerized with boron trifluoride, the product consists of 50-70% 1,4-adducts. A veiy high trans-1,4-poly(2-chloro-1,3-butadiene) forms by X-ray radiation polymerization of large crystals of... 

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