The asymmetriccopper-catalyzedconjugateaddition to α-alkylidene cycloalkanones, substituted at their terminal position with aromatic and aliphatic groups, is reported. While high enantioselectivity is reached using chiral phosphoramidite ligands, with R3Al reagents, moderate diastereoselectivity was observed upon hydrolysis of the aluminium enolates. A Grignard reagent also react with high diastereoselectivity
Anodic oxidation of triphenylphosphine in the presence of enol silyl ethers or enol esters. Electrochemical one-step preparation of 2-oxocycloalkyltriphenylphosphonium tetrafluoroborates
Electrochemical oxidation of triphenylphosphine in the presence of cyclic enol silyl ethers or enolesters gave 2-oxocycloalkyltriphenylphosphonium salts, which underwent the Wittig reaction with aldehydes to afford (E)-2-alkylidenecycloalkan-1-ones.
A New Lewis Acid System Palladium/TMSCl for Catalytic Aldol Condensation of Aldehydes with Ketones
作者:Yulin Zhu、Yuanjiang Pan
DOI:10.1246/cl.2004.668
日期:2004.6
catalyzed the aldolcondensation reactions of different ketones with aldehydes in the presence of trimethylsilyl chloride (TMSCI). The following reactions were investigated: (1) aromaticaldehydes with cycloalkanones, (2) aromaticaldehydes with aromatic ketones, (3) cycloalkanones with aliphatic aldehydes, and (4) the self-condensation reactions of aliphatic aldehydes and cycloalkanones.
The present invention relates to the field of perfumery. More particularly, it concerns a compound of formula (I) as defined herein below, and its uses as perfuming ingredients. Therefore, following what is mentioned herein, the present invention comprises the invention compound as part of a perfuming composition or of a perfumed consumer product. Moreover, the present invention relates to a properfume compound suitable to release the compound of formula (I).
Catalytic Asymmetric Construction of Spirocycles Containing Pyrrolidine Motifs and Spiro Quaternary Stereogenic Centers via 1,3-Dipolar Cycloaddition of Azomethine Ylides with 2-Alkylidene-Cycloketones
作者:Tang-Lin Liu、Zhao-Lin He、Qing-Hua Li、Hai-Yan Tao、Chun-Jiang Wang
DOI:10.1002/adsc.201100104
日期:2011.7
The first catalyticasymmetric 1,3‐dipolar cycloaddition of azomethineylides with various sterically hindered α,α,β‐trisubstituted 2‐alkylidene‐cycloketones has been developed successfully with silver acetate/TF‐BiphamPhos complex for the construction of spiro heterocyclic compounds containingpyrrolidine motifs and a spiro quaternary stereogenic carbon center. The highly efficient catalytic system exhibited