The Pd(II)-catalyzed one-pot tandem cyclization/alkylation reactions of enynoates with allylic alcohols have been demonstrated. In this reaction, an innovative protocol proceeded well through Pd-catalyzed intramolecular selective 6-endo cyclization, insertion of allylic alcohols into the Pd–C bond of vinylpalladium species generated in situ, and β-hydrogen elimination processes. This conversion provides
A Pd(II)-catalyzed mild and highly regioselective 6-endo cyclization/allylation reaction of enynoates with simple allylic alcohols has been developed. Under mild reaction conditions, the vinyl palladium species generated in situ after cyclization could insert C–C double bond of allylic alcohol through cross-coupling reaction and lead to the formation of allyl pyrone via β-OH elimination. This cascade
Unexpected Multiple Electrophilic Addition Reaction of (<i>Z</i>)-Alk-2-en-4-ynoates with <i>N</i>,<i>N</i>-Dibromo-<i>p</i>-toluenesulfonamide (TsNBr<sub>2</sub>): A Highly Diastereoselective Synthesis of Densely Functionalized Aziridines
作者:Ruwei Shen、Xian Huang
DOI:10.1021/ol902446h
日期:2009.12.17
;A novel electrophilic addition reaction of (Z)-alk-2-en-4-ynoates and TsNBr2 is reported, providing a facile and highly stereoselective synthesis of densely functionalized aziridine derivatives.
Regiodivergent Hydrosilylation of Polar Enynes to Synthesize Site‐Specific Silyl‐Substituted Dienes
Herein, we present catalyst‐regulated switchable site‐selective hydrosilylation of enynes, which are suitable for a wide range of alkyl and aryl substituted polar enynes and exhibit excellent functional group compatibility. Under the optimized conditions, silyl groups can be precisely installed at various positions of 1,3‐dienes. While α‐ and γ‐silylation products were obtained under platinum‐catalytic systems, β‐silylation products were delivered with [Cp*RuCl]4 as catalyst. This process lead to the formation of 1,3‐dienoates with diverse substitutions, which would pose challenges with other methodologies.