Synthesis of methyl 2-oxo-5-vinyl-2,5-tetrahydrofuran-3-carboxylate
作者:Maximilian A. Silvestri、Chang He、Anita Khoram、Salvatore D. Lepore
DOI:10.1016/j.tetlet.2005.12.114
日期:2006.3
A synthesis of methyl 2-oxo-5-vinyl-tetrahydrofuran-3-carboxylate involving five synthetic steps from commercially available 3,4-dihydroxybutene is reported. (c) 2006 Elsevier Ltd. All rights reserved.
The Preparation of 5-Alkyl-5-(β-phenyl- and β-Vinyl-β-hydroxyethyl)-barbituric Acids Via the Corresponding α-Carbethoxy-γ-butyrolactones
作者:Gerrit Van Zyl、Eugene E. van Tamelen
DOI:10.1021/ja01159a075
日期:1950.3
Bis(trimethylsilyl) sulphate catalyzed γ-lactonization of cyclopropanecarboxylates having a carbonyl substituent at cyclopropane α-carbon
The title reaction of 1-carbonyl substituted cyclopropanecarboxylates proceeds under C(1)–C(2) bond cleavage to produce γ-lactones. Stereochemically, the reaction takes two pathways: (1) substrates with a cationstabilizing group like vinyl on C(2) give thermodynamically favored γ-lactones having the thermodynamically more stable arrangement of substituents irrespective of the configuration of the cyclopropane substrates, (2) substrates without such a cation-stabilizing group afford γ-lactones under ca. 70% inversion at C(2) reaction center.