Aldol additions of pinacolone lithium enolate with ketones: reactivities governed predominantly by field effects
作者:Goutam Das、Edward R. Thornton
DOI:10.1021/ja00057a012
日期:1993.2
The relative reactivities of representative α- and β-heterosubstituted acyclic, cyclic (five- and six-membered), and aromatic ketones with the lithiumenolate of pinacolone in diethyl ether at -78 o C were determined. The order of reactivitiesof monosubstituted acetones (MeCOCH 2 X) is X=Cl>OTBDMS>OMe>SMe>NMe 2 >CH 2 SM>H>Me and spans a range of 10 4
测定了代表性的 α- 和 β- 杂取代的无环、环状(五元和六元)和芳香酮与频哪酮的烯醇锂在 -78 o C 的二乙醚中的相对反应性。单取代丙酮 (MeCOCH 2 X) 的反应性顺序为 X=Cl>OTBDMS>OMe>SMe>NMe 2 >CH 2 SM>H>Me,范围为 10 4
Efficient Intramolecular Cyclizations of Phenoxyethynyl Diols into Multisubstituted α,β-Unsaturated Lactones
AgOTf-catalyzed intramolecular cyclization of phenoxyethynyl diols proceeded under mild conditions to afford the multisubstituted alpha,beta-unsaturated-gamma-lactones in 55-98% yields. This method was also applicable to the synthesis of alpha,beta-unsaturated-delta-lactones. A similar cyclization proceeded when AgOTf was replaced with a stoichiometric amount of N-bromosuccinimide to furnish the a-bromo-substituted alpha,beta-unsaturated lactones.
Iron-Mediated Electrochemical Reaction of α-Chloroesters with Carbonyl Compounds
Reformatsky-type reactions have been performed efficiently using an electroassisted iron-complex catalysis. Valuable product such as beta-hydroxyesters, ketones or nitriles are thus prepared with high yields.
Reactions involving electron transfer. 10. The use of .beta.-cyclopropyl .alpha.,.beta.-unsaturated ketones to detect anion radical intermediates
作者:Herbert O. House、Karel Snoble
DOI:10.1021/jo00881a002
日期:1976.9
Sosnovskikh, V. Ya.; Esafov, V. I.; Andreev, N. S., Journal of Organic Chemistry USSR (English Translation), 1981, vol. 17, # 11, p. 2096 - 2100
作者:Sosnovskikh, V. Ya.、Esafov, V. I.、Andreev, N. S.