The 1,4-addition of organotitaniumatecomplexes to enones by nickel catalysis is reported. With a methyltitanium atecomplex good yields of conjugate addition to stericallyhinderedenones are achieved. Phenyltitanium atecomplexes react with less sterically encumbered enones to the 1,4-addition products in moderate to high yields.
Nickel acetylacetonate is an efficient catalyst for the 1,4-addition of trimethylaluminum to α,β-unsaturated ketones. The reaction is strongly solvent dependent and gives best results in tetrahydrofuran or ethyl acetate. The reaction is especially useful for the nucleophilic 1,4-methyl transfer to sterically hindered enones. A β-cuparenone synthesis via conjugate methyl group addition to an enone precursor is described.
Total synthesis of the sesquiterpene (±)β-cuparenone: use of three-carbon annulation in synthesis
作者:Michael E. Jung、C.David Radcliffe
DOI:10.1016/s0040-4039(00)92183-x
日期:——
A totalsynthesis of β-cuparenone, which highlights the advantages and disadvantages of the three-carbon annulationprocess, is described.
描述了β-cuparenone的全合成,突出了三碳环化工艺的优缺点。
Novel Synthetic Approach Toward (±)-β-Cuparenone via Palladium-Catalyzed Tandem Heck Cyclization of 1-Bromo-5-methyl-1-aryl-hexa-1,5-dien-3-ol Derivatives
作者:Devalina Ray、Jayanta K. Ray
DOI:10.1021/ol062418t
日期:2007.1.1
A novel and convenient synthetic route toward (+/-)-beta-cuparenone and many other sesquiterpene natural product precursors has been developed via palladium-catalyzed tandem Heck cyclization of 1-bromo-5-methyl-1-aryl-hexa-1,5-dien-3-ols. [reaction: see text].
A unified approach to sesquiterpenes sharing trimethyl(p-tolyl) cyclopentanes: Formal total synthesis of (±)-laurokamurene B
作者:Mrinal K. Das、Bidyut K. Dinda、Vishnumaya Bisai
DOI:10.1016/j.tetlet.2019.05.032
日期:2019.8
A unified approach to the sesquiterpenoids sharing common trimethyl(p-tolyl) cyclopentane skeleton has been disclosed via a key Stork-Danheiser sequence on a cyclopentane based vinylogous ester with aryl Grignard reagent followed by α-methylation strategy. The strategy is eventually applied to the concise formaltotalsynthesis of (±)-laurokamurene B (1b) in only 5 steps with 45.4% overall yield.