A new cyclopentene annulation method based on a conjugate additionreaction with 4-methoxybut-3-enenitrile was developed. Treatment of a cyclic enone with the potassium carbanion of the nitrile followed by acetic anhydride afforded an enol acetate, which underwent an HCl-mediated intramolecular cyclization reaction to yield a bicyclo[n.3.0]alkenone derivative in good yield. A lipase-mediated optical
Steric and complexation effects on the 1,4-addition reaction of lithium dimethylcuprate with rigid α,β-unsaturated ketones
作者:A.Samuel Vellekoop、Robin A.J. Smith
DOI:10.1016/s0040-4020(98)83052-4
日期:1998.9
Reaction of lithiumdimethylcuprate with a series of substituted 10-methyl-1(9)-octal-2-ones in diethyl ether give 1,4-addition products with the same ring junction stereochemistry as the parent, unsubstituted α,β-unsaturated ketone. The reactivity of the system is modified by groups positioned axially and 1,3 with respect to the β-carbon of the enone. Alkoxy substituents are generally activating,
Studies on sesquiterpenoids. Part XVII. Total synthesis of (±)-lindestrene
作者:Hitoshi Minato、Tohru Nagasaki
DOI:10.1039/j39680000621
日期:——
9-Methyl-Δ5(10)-octalin-1,6-dione has been converted into 4,4a,5,6,8a,9-hexahydro-3,8a-dimethyl-5-methylenenaphtho[2,3-b]furan, which is identical (i.r., g.l.c.) with (±)-lindestrene, a furan sesquiterpene previously isolated from Lindera strychnifolia Vill.
9-甲基-Δ5 (10)-辛基-1,6-二酮已转化为4,4a,5,6,8a,9-六氢-3,8a-二甲基-5-亚甲基萘[2,3- b ]呋喃,与(±)-lindestrene(先前从Lindera strychnifolia Vill中分离出的呋喃倍半萜烯)相同(ir,glc)。