The reaction of photochemically generated α-hydroxyalkyl radicals with alkynes: a synthetic route to γ-butenolides
作者:Niall W.A. Geraghty、Elaine M. Hernon
DOI:10.1016/j.tetlet.2008.11.067
日期:2009.2
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
α-Hydroxy carbon radicals generated from alcohols by the action of NHPI smoothly added to electron-deficient alkynes like acetylenedicarboxylates. For instance, the reaction of 2-propanol with dimethyl acetylenedicarboxylate afforded maleate derivative 3, 3-methoxycarbonyl-4,4-dimethyl-2-buten-4-olide (4), and a fused bis-γ-butyrolactone 5 formed by further addition of 2-hydroxy-2-propyl radical to 4.
Carbonylation of acetylenic compounds. 1. Carbonylation of tertiary acetylenic alcohols
作者:B. P. Gusev、E. A. �l'perina、V. F. Kucherov、S. D. Plrozhkov、A. L. Lapidus
DOI:10.1007/bf00949627
日期:1980.3
GUSEV B. P.; EHLPERINA E. A.; KUCHEROV V. F.; PIROZHKOV S. D.; LAPIDUS A.+, IZV. AN CCCP. CEP. XIM., 1980, HO 3, 603-607
作者:GUSEV B. P.、 EHLPERINA E. A.、 KUCHEROV V. F.、 PIROZHKOV S. D.、 LAPIDUS A.+
DOI:——
日期:——
Bromine-Induced Facile Synthesis of Butenolides and Spirobutenolides from Sterically Congested Tetrasubstituted Dialkyl Alkylidene Succinates
作者:Narshinha Argade、Ramesh Patel
DOI:10.1055/s-0029-1219233
日期:2010.4
Starting from sterically congested tetrasubstituted dialkyl alkylidene succinates, facile general approach to several dialkyl substituted butenolides and spirobutenolides with the generation of quaternary carbon center has been demonstrated via bromine-induced dealkylative regioselective intramolecular cyclization and dehydrobromination pathway. The mechanistic aspects involved in the formation of butenolides have been also described in brief.