are obtained by reaction of AlH3 with pyrrolidine enamines of acyclic and cyclic ketones. Enamines of α-substituted cyclohexanones are converted to 3-alkylcyclohexenes. Those derived from disubstituted acetaldehydes are only poorly hydrogenolysed as is the dienamine derived from Δ1,9-octalone. 1-N-Pyrrolidinocyclo-octene is unique in giving cyclo-octane in the hydrogenolysis reaction; trans-cyclo-octene
Reaction of Enamines with Acetals or Trialkyl Orthoformates Activated by Lewis Acids
作者:Osamu Takazawa、Kunio Kogami、Kazuo Hayashi
DOI:10.1246/bcsj.57.1876
日期:1984.7
Enamines, prepared readily from various carbonyl compounds, react with acetals or trialkyl orthoformates in the presence of Lewis acids such as BF3·OEt2 to give corresponding β-alkoxy carbonyl compounds or α-dialkoxymethyl carbonyl compounds in good yields. The reaction of dienamines with acetals or trialkyl orthoformates also selectively gives corresponding β,γ-unsaturated α-(α-alkoxyalkyl) carbonyl compounds
Enamines: efficient nucleophiles for the palladium-catalyzed asymmetric allylic alkylation
作者:Xiaohu Zhao、Delong Liu、Fang Xie、Wanbin Zhang
DOI:10.1016/j.tet.2008.11.003
日期:2009.1
Enamines were tested to be efficient nucleophiles for palladium-catalyzedasymmetric allylic alkylation, avoiding the use of unstablilized ketoneenolates formed by strong bases. The influence of the chiral metallocene-based ligands upon this reaction was studied in detail. It was shown that planar chirality played an important role in enantioselectivities. Meanwhile, different kinds of enamines and
Benzyne reaction. Part X. The benzyne reaction of ortho-substituted halogenobenzenes with cyclohexanone in secondary cyclic amines or in organic solvents
2-Arylcyclohexanones have been synthesised by the benzynereaction of o-substituted halogenobenzenes with cyclohexanone or its enamine in the presence of sodium amide in tetrahydrofuran or in secondary cyclic amines.
ions. Such a ranking holds promise for expanding the range of couplingreactions which can be envisioned with such strongly electron-deficient neutral heteroaromatics as nitrobenzofuroxans and related compounds. Arguments are also given which exclude the possibility for the reactions studied to proceed via an electron-transfer mechanism.