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Please login or sign up for a free trial to access the full content. Synthesis by Heteroatom Substitution: Substitution of Hydroxy or Tetrahydropyranyl Ether Groups

DOI: 10.1055/sos-SD-135-00224

Braun, M.Science of Synthesis Knowledge Updates, (20171457.

Various procedures that permit the conversion of non-activated aliphatic alcohols into the corresponding bromoalkanes, as described in Section, have been extended to propargylic alcohols, either as the free alcohols or in the tetrahydropyran-2-yl (THP) protected form. A survey of these protocols, including the relevant reagents and conditions, is given in Scheme 1.[‌1‌‌6‌] Commonly, sources of bromine (e.g., Br2, LiBr, CBr4) are used in combination with phosphorus reagents (phosphines, phosphites, phosphine oxides), but 2,2-dibromoimidazole-4,5-dione 1 and dibromo ester 2 may also be used.

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