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35.2.1.5.2.8 Variation 8: Reaction of Alcohols with Triphenylphosphine–Carbon Tetrabromide and Related Reagents

DOI: 10.1055/sos-SD-035-00308

Braun, M.Science of Synthesis, (200735333.

The reaction of alcohols with triphenylphosphine and carbon tetrabromide is a mild and efficient method for the preparation of primary and secondary alkyl bromides 15. Primary hydroxy groups have been shown to react selectively in the presence of secondary ones. The method has been used frequently in carbohydrate and nucleoside-type substrates as well as with sensitive substrates containing allenyl moieties. It leads to complete inversion at stereogenic hydroxy-bearing carbon atoms. Illustrative examples are shown in Scheme 15.

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