L. Kudzma, Chialang G. Huang, R. Lessor
Sep 28, 2001
Citations
0
Influential Citations
9
Citations
Journal
Journal of Fluorine Chemistry
Abstract
Abstract Diisopropylethylamine mono(hydrogen fluoride) ( 8 ), which can be prepared by addition of two equivalents of diisopropylethylamine to the complex diisopropylethylamine tris(hydrogen fluoride) ( 7 ), is shown to be an effective and selective nucleophilic fluorinating reagent when applied to halogen-exchange reactions of chloromethyl ethers, in particular the conversion of 1,1,1,3,3,3-hexafluoroisopropyl chloromethyl ether ( 3 ) to the volatile anesthetic sevoflurane (1,1,1,3,3,3-hexafluoroisopropyl fluoromethyl ether). The amine portion of the reagent does not react with the starting material to give a troublesome quaternary ammonium salt, as is the case for the species formed by addition of two equivalents of triethylamine to triethylamine tris(hydrogen fluoride). These particular chloromethyl ether substrates require a 1:1 stoichiometry of diisopropylethylamine to hydrogen fluoride to give useful rates of reaction and yields when solventless conditions are desired. Two other complexes, diisopropylethylamine bis(hydrogen fluoride) and 7 , are ineffective for conversion of 3 to sevoflurane.