New synthesis of jasmine lactone and related .delta.-lactones from 1,2-cyclohexanedione. Preparation and dye-sensitized photooxygenation of 3-(2-alkenyl)- and 3-(2-alkynyl)-1,2-cyclohexanediones
One-Pot Sequential 1,4- and 1,2-Reductions of α,β-Unsaturated δ-Lactones to the Corresponding δ-Lactols with CuCl and NaBH4 in Methanol
作者:Yasunobu Matsumoto、Masahiro Yonaga
DOI:10.1055/s-0033-1340195
日期:——
An efficient, one-pot method for the highly chemoselective synthesis of δ-lactols fromα,β-unsaturatedδ-lactones using CuCl and NaBH4 in methanol was developed.
Baeyer-Villiger Oxidation with Me<sub>3</sub>SiOOSiMe<sub>3</sub>under Assistance of SnCl<sub>4</sub>or BF<sub>3</sub>·OEt<sub>2</sub>
作者:Seijiro Matsubara、Kazuhiko Takai、Hitosi Nozaki
DOI:10.1246/bcsj.56.2029
日期:1983.7
Treatment of ketones with bis(trimethylsilyl) peroxide and Lewis acid such as SnCl4 or BF3·OEt2 in dichloromcthane at room temperature affords esters in fair to excellent yields. Jasmine lactone is synthesized from 2-[(Z)-2-pentenyl]cyclopentanone by means of Me3SiOOSiMe3–BF3·OEt2 system without any protection of the carbon-carbon double bond. The oxidation of enol acetates of ketones to α-hydroxy (or α-acetoxy) ketones with Me3SiOOSiMe3–FeCl3 system is also disclosed.
A general electron transfer reduction of lactones using SmI2–H2O
作者:Michal Szostak、Karl D. Collins、Neal J. Fazakerley、Malcolm Spain、David J. Procter
DOI:10.1039/c2ob00017b
日期:——
transfer reduction of lactones of all ring sizes and topologies using SmI2–H2O and a Lewis base to tune the redox properties of the complex. The current protocol permits instantaneous reduction of lactones to the corresponding diols in excellent yields, under mild reaction conditions and with useful chemoselectivity. We demonstrate the broad utility of this transformation through the reduction of complex
Reductive Cyclization Cascades of Lactones Using SmI<sub>2</sub>−H<sub>2</sub>O
作者:Dixit Parmar、Kieran Price、Malcolm Spain、Hiroshi Matsubara、Paul A. Bradley、David J. Procter
DOI:10.1021/ja1114908
日期:2011.3.2
Lactones bearing two alkenes or an alkene and an alkyne undergo reductive cyclization cascades upon treatment with SmI(2)-H(2)O, giving decorated azulene motifs in excellent yields with good diastereocontrol.
A newsynthesis of jasmine lactone and related δ-lactones is described which uses a novel dye-sensitized photooxygenation of 3-(2-alkenyl)- or 3-(2-alkynyl)-1,2-cyclohexanediones as a key step.