Nanoporous aluminosilicate, Al-HMS with a high aluminum content, strong acidity, and nanoporosity was found to catalyze the Diels-Alderreaction of 1,3-dienes with methacrylate and acrylate, and turned out to be a green alternative to homogeneous acid catalysts.
Stereochemistry of an Ene Reaction Involving 1,7-Dienes; Bicyclo[3.3.1]nonanes from (3-Cyclohexenyl)diallylcarbinols
作者:Alan F. Thomas、Marina Lander-Schouwey
DOI:10.1002/hlca.19840670124
日期:1984.2.1
(3-Cyclohexenyl)diallylcarbinols undergo a thermal retro-enereaction to give crotonylcyclohexenes at ca. 200°. A side-reaction is an enereaction to give bicyclo[3.3.1]nonanes. These become the main products above 300°. The stereochemistry of 2-allyl-1,4,6-trimethylbicyclo[3.3.1]-6-none-2-ols and related compounds is discussed, and a case is described in which the allyl group is not freely rotating.
General Synthesis of Ketones from Carboxylic Esters and Carboxamides by Use of Mixed Organolithium-Magnesium Reagents: Syntheses of Artemisia Ketone
作者:Charles Fehr、Jos� Galindo、Roland Perret
DOI:10.1002/hlca.19870700710
日期:1987.11.4
The novel reagents formed by combination of Grignardreagents (RMgX) with lithium diisopropylamide (LDA) convert non-enolizable or slowly enolizable carboxylicesters or caboxamides into ketones which are protected from further reaction by their in situ conversion into enolates. These enolates can be trapped with electrophiles such as Me3SiCl and allyl bromide. The scope of this Grignard mono-addition
An efficient and highly regioselective intramolecular Mannich-type reaction: A construction of the AEF ring system of aconitine-type diterpene alkaloids
An efficient and highly regioselective intramolecular Mannich-type reaction has been developed. The utility of the methodology, combined with a stereoselective intramolecular Diels-Alder reaction, for the construction of the AEF ringsystem of aconitine-type alkaloids has been exemplified.
Synthesis of (E)-1-Propenyl Ketones from Carboxylic Esters and Carboxamides by Use of Mixed Organolithium-Magnesium Reagents. Synthesis of ?-Damascone, ?-Damascone, and ?-Damascenone
作者:Charles Fehr、Jos� Galindo
DOI:10.1002/hlca.19860690127
日期:1986.2.5
The novel reagents formed by combination of allylmagnesium chloride and a strong non-nucleophilic lithium base (LiNR2) convert non- or slowly enolizable carboxylic esters or carboxamides into 2-propenyl ketones which are protected from further reaction by their in situ conversion into enolates. This modified Grignardreaction is applied to efficient syntheses of α-damascone, β-damascone, β-damascenone