TY - JOUR
T1 - The reaction of photochemically generated α-hydroxyalkyl radicals with alkynes
T2 - a synthetic route to γ-butenolides
AU - Geraghty, Niall W.A.
AU - Hernon, Elaine M.
PY - 2009/2/4
Y1 - 2009/2/4
N2 - The photomediated generation of α-hydroxyalkyl radicals from simple acyclic and cyclic alcohols, and acyclic diols, and their subsequent carbon-carbon bond forming reaction with propiolate esters and acetylenedicarboxylates, gives a mixture of a β-(hydroxyalkyl)enoate, the result of a formal cis addition, and the unsaturated lactone (γ-butenolide) resulting from the spontaneous cyclization of the corresponding trans addition product. Treatment of the cis adduct with NBS converts it to the same lactone, and so the method overall constitutes a particularly direct route to this important structural unit. Cyclic alcohols give rise to spiro-γ-butenolides. The use of supported photomediators simplifies product isolation and allows for the recovery and reuse of the photomediator.
AB - The photomediated generation of α-hydroxyalkyl radicals from simple acyclic and cyclic alcohols, and acyclic diols, and their subsequent carbon-carbon bond forming reaction with propiolate esters and acetylenedicarboxylates, gives a mixture of a β-(hydroxyalkyl)enoate, the result of a formal cis addition, and the unsaturated lactone (γ-butenolide) resulting from the spontaneous cyclization of the corresponding trans addition product. Treatment of the cis adduct with NBS converts it to the same lactone, and so the method overall constitutes a particularly direct route to this important structural unit. Cyclic alcohols give rise to spiro-γ-butenolides. The use of supported photomediators simplifies product isolation and allows for the recovery and reuse of the photomediator.
UR - https://www.scopus.com/pages/publications/57549097799
U2 - 10.1016/j.tetlet.2008.11.067
DO - 10.1016/j.tetlet.2008.11.067
M3 - Article
SN - 0040-4039
VL - 50
SP - 570
EP - 573
JO - Tetrahedron Letters
JF - Tetrahedron Letters
IS - 5
ER -