Both 2:1 and 1:1 couplings of alkylacetylenes with secondary amines were achieved using 8-quinolinolato rhodium catalysts and CsF. The 2:1/1:1 selectivity was switched by choosing the reaction solvent. In DMA, an unprecedented 2:1 coupling reaction of alkylacetylenes with amines proceeded to give 2-aminodiene products. One-pot 2:1 coupling/reduction provided rapid access to various allylamines, while
Iron-Catalyzed α-Methylenation of Ketones with<i>N</i>,<i>N</i>-Dimethylacetamide: An Approach for α,β-Unsaturated Carbonyl Compounds
作者:Yi-Ming Li、Shao-Jie Lou、Qin-Hua Zhou、Lian-Wen Zhu、Long-Feng Zhu、Lei Li
DOI:10.1002/ejoc.201500189
日期:2015.5
this study, we developed a general iron-catalyzedα-methylenation of ketones by using N,N-dimethylacetamide as the one-carbon source. Various ketones, including aryl and alkyl ketones, enones, and dicarbonyl compounds were well tolerated to yield the corresponding α,β-unsaturatedcarbonylcompounds in the presence of an iron catalyst, peroxides, and N,N-dimethylacetamide under aerobic conditions.
A novel enantioselective protonation protocol that is triggered by reductive cross coupling of olefins is reported. When under cooperative photoredox and chiral hydrogen-bonding catalytic conditions and using a terminal reductant, various α-branched vinylketones with diverse vinylazaarenes could provide important enantioenriched azaarene derivatives containing tertiary stereocenters at their remote
An Efficient and Convenient Method for the Preparation of α-Methylenated Ketones from Silyl Enol Ethers
作者:Masaji Hayashi、Teruaki Mukaiyama
DOI:10.1246/cl.1987.1283
日期:1987.7.5
In the presence of a catalytic amount of stannous halide, silyl enol ethers react with bromomethyl methyl ether to give the corresponding α-bromomethyl ketones, which are smoothly converted to α-methylenated ketones on the successive addition of tertiary amine by one-pot procedure. This method is successfully applied to a synthesis of sarkomycin intermediate.
Ionic liquid catalysed reaction of thiols with α,β-unsaturated carbonyl compounds—remarkable influence of the C-2 hydrogen and the anion
作者:Anirban Sarkar、Sudipta Raha Roy、Asit K. Chakraborti
DOI:10.1039/c1cc10151j
日期:——
Hydrogen bond induced reactivity and selectivity control in the 1-butyl-3-methylimidazolium based ionic liquid catalysed reaction of thiols with α,β-unsaturated carbonyl compounds is reported with remarkable influence of the anion and the C-2 hydrogen in catalytic activity and reversal of selectivity.