Boron trifluoride ethyl etherate

An alternative diborane source was used by the checker. Diborane was generated by adding boron trifluoride-ethyl ether to sodium tetrahydroborate (sodium borohydride) in ether. The generator was charged to yield a maximum of 0.6 mol of... 

With this idea in mind, Deslongchamps treated the cw-decalin-2,7-dione (12) with a mixture of acetic anhydride-acetic acid in the presence of boron trifluoride ethyl etherate, at room temperature, and the twistanone 20 was isolated in 75% yield. The whole synthetic sequence is outlined in Scheme 13.1.7. 

Commercial boron trifluoride ethyl etherate (from Mathe-son Coleman and Bell) is distilled in an all glass apparatus at 46° (10 mm.) from a few pieces of granular calcium hydride. The latter serves to remove small quantities of volatile acids and greatly reduces bumping during distillation. 

Available forms Crystalline powder, dry amorphous powder, colloidal suspension of dry amorphous powder in oil in boron trifluoride-calcium fluoride, in potassium borofluoride, in boron trifluoride ethyl etherate, in boric acid. 

PVME was polymerized cationically with boron-trifluoride-ethyl ether complex as a catalyst the fraction with M = 1,690,000 was used for preparing the blends. PSD, with M > 4,000,000, was prepared by emulsion polymerization. 

Alternate Names boron trifluoride diethyl etherate boron trifluoride ethyl etherate boron trifluoride ethyl ether complex trifluoroboron diethyl etherate. 

Propose a mechanism for the following pinacol rearrangement catalyzed by boron trifluoride ethyl etherate. 

In contrast, in the presence of boron trifluoride ethyl ether complex the potential of benzene oxidation was reduced less than with SbFs, in agreement with the fact that the interaction between the benzene and the etherate is weaker than with SbFs. The PPP films formed in this medium had a metallic aspect, were electroactive, homogeneous and adhered strongly to the electrode [142]. 

Antimony pentachloride Boron trichloride gas Boron trifluoride gas Boron trifluoride ethyl etherate Boron trifluoride methyl etherate Bromine trifluoride Phosphorus oxychloride Phosphorus pentachloride Phosphorus tribromide... 

Preparation by reaction of 3,4-xylenol with benzoic acid in the presence of boron trifluoride-ethyl ether complex, at 128-129° for 7 min, followed by treatment of the difluoroboroxy chelate formed with boiling aqueous ethanol for 15 min (63%) [729]. 

Preparation by reaction of cyclohexene with 3,4-di-hydroxy-2, 5-dinitrobenzo-phenone in the presence of boron trifluoride ethyl ether complex for 12 h at reflux (24%). -Refer to Chem. Abstr., 127, 17465U (1997). 

JJ 2-methyl-resorcinol with boron trifluoride-ethyl ether... 

Oishi and his co-workers have reported that aromatic thiono-esters (408), in the presence of boron trifluoride ethyl-etherate, rearrange to the corresponding thiolo-esters (409). The disappearance of the thiono-ester took place in accordance with first-order kinetics, and electron-donating para-substituents were found to accelerate the conversion, which was characterized by the Hammett p value of -1.38. The mechanism of the rearrangement was considered to involve the intermediate (410), in agreement with the results of cross-over experiments. The thermal rearrangement of thioaroyl thiocyanates (411) to thioaroyl isothiocyanates (412) was also found to be influenced by substituents. Thiono-ester-thiolo-ester... 

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