Boron trifluoride diethyl etherate is used as a Lewis acid catalyst in Mukaiyama aldol addition, alkylation, acetylation, isomerization, dehydrations and condensation reactions. It is involved in the prepattion of polyethers in polymerization reactions. As a catalyst, it is used in the preparation of cyclopentyl- and cycloheptyl[b]indoles and other diborane. It is also used in sensitive neutron detectors in ionization chambers as well as monitoring radiation levels in earths atmosphere.
Lewis acid catalyst in a wide variety of applications, for example:
Mild dehydration of tertiary alcohols to alkenes: Tetrahedron Lett., 32, 6489 (1991). In the Diels-Alder reaction: J. Am. Chem. Soc., 99, 8116 (1977). In THP protection of alcohols: Synthesis, 81, (1972).
Reaction with Sodium borohydride, 35788, can be used for the in situ generation of diborane. For use in the hydroboration of ɑ-pinene, see: Org. Synth. Coll., 6, 943 (1988).
Has also been used in conjunction with BMS in the reduction of amides: J. Org. Chem., 47, 3153 (1982).
For use in the cleavage of ethers, see Tetra-n-butylammonium iodide, A15484.
Catalyst for rearrangement of epoxides to carbonyl compounds, e.g. stilbene oxide to diphenylacetaldehyde and ring-contraction of isophorone oxide: Org. Synth. Coll., 4, 375 and 957 (1963), respectively.
Reaction with ortho esters gives high yields of crystalline dialkoxycarbenium salts, useful as powerful and selective alkylating agents, (compare Triethyloxonium tetrafluoroborate, A14420 and Trimethyloxonium tetrafluoroborate, A15175): Synth. Commun., 19, 2307 (1989).
Catalyst for the reaction of allyltin reagents with aldehydes and ketones. Addition to the carbonyl group proceeds with allylic rearrangement: Chem. Lett., 919, 977 (1979); Acc. Chem. Res., 20, 243 (1987):
For analogous 1,4-addition to p-benzoquinones, see 2,3-Dimethoxy-5-methyl-1,4-benzoquinone, B24777.
Dolas, H.; Sarac, A. S. An impedance-morphology study on poly(3-methylthiophene) coated electrode obtained in boron trifluoride diethyl etherate-acetonitrile. Synth. Met. 2014, 195, 44-53.
Mo, D.; Zhou, W.; Ma, X.; Xu, J. Facile electrochemical polymerization of 2-(thiophen-2-yl)furan and the enhanced capacitance properties of its polymer in acetonitrile electrolyte containing boron trifluoride diethyl etherate. Electrochim. Acta. 2015, 155, 29-37.
Gefahrenhinweise (EU): H226-H302-H331-H314-H318-H372
Flammable liquid and vapour. Harmful if swallowed. Toxic if inhaled. Causes severe skin burns and eye damage. Causes serious eye damage. Causes damage to organs through prolonged or repeated exposure.
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