Synthesis and stereochemistry of 8-methyl-5-nitro-1-octalones
摘要:
Base catalyzed Michael addition of 5-nitropentan-2-one ethylene ketal (I) and cyclohex-2-enone (2), subsequent deprotection, and intramolecular aldol condensation yields the 8-methyl-5-nitro-1-octalone isomers (5a, b). The structure, relative configuration, and conformation of 5a and 5b were elucidated utilizing the results of H-1 and C-13 NMR investigations
Phase-Transfer-Catalyst-Mediated Domino Reaction of γ-Nitro Ketones with Chalcones: Approach to Functionalized Six-Membered-Ring Carbocycles
作者:Lu Yu、Qingjing Yang、Pengfei Li
DOI:10.1002/ejoc.201403075
日期:2014.11
Dominoreactions between γ-nitroketones and chalcones for the construction of functionalizedsix-membered-ringcarbocycles using a phase-transfer catalyst have been developed. In the presence of tetrabutylammonium iodide and potassium hydroxide, dominoreactions between γ-nitroketones and a series of chalcones proceeded smoothly to give the cyclic products in moderate to high yields with high di
Denitration of various important intermediates in the synthesis of sorgolactone and itsanalogs using radical chemistry on nitroketones or on the derived isocyanides is described. The nitro group is needed for the first step of the annellation process, the Michael addition of substituted nitroalkanes to cyclopentenones. Then it can be removed directly or after reduction to the amine or via the ketone
Base catalyzed Michael addition of 5-nitropentan-2-one ethylene ketal (I) and cyclohex-2-enone (2), subsequent deprotection, and intramolecular aldol condensation yields the 8-methyl-5-nitro-1-octalone isomers (5a, b). The structure, relative configuration, and conformation of 5a and 5b were elucidated utilizing the results of H-1 and C-13 NMR investigations