The reaction of thioacetals of phenyl ketones, α,α-bis(trimethylsilyl)alkyl sulfides, and 2-alkyl-2-ethylthioalkanenitriles with tributylstannyllithium gave the corresponding α-anions of sulfides, α,α-bis(trimethylsilyl)alkane, and nitriles, respectively.
Activation of Alcohols with Carbon Dioxide: Intermolecular Allylation of Weakly Acidic Pronucleophiles
作者:Simon B. Lang、Theresa M. Locascio、Jon A. Tunge
DOI:10.1021/ol502023d
日期:2014.8.15
coupling of allyl alcohols with nitroalkanes, nitriles, and aldehydes using catalytic Pd(PPh3)4 has been accomplished viaactivation of C–OH bonds with CO2. The in situ formation of carbonates from alcohols and CO2 facilitates oxidativeaddition to Pd to form reactive π-allylpalladium intermediates. In addition, the formation of a strong baseactivates nucleophiles toward the reaction with the π-allylpalladium
clean method has been developed for the α‐allylation of phenyl and alpha alkyl phenyl acetonitrile with allylic alcohols. The reaction is catalyzed by nickel complexes in situ generated from a combination of Ni(cod)2 and the dppf ligand and performed at 80 °C in methanol as reaction solvent. Accordingly to this simple and base‐free protocol that only yields water as a side‐product, many allylic nitriles
Transformations of<i>N</i>-Allyl-<i>N</i>-(phenylethynyl)arenesulfonamides into 2,2-Disubstituted 4-Pentenenitriles through Aza-Claisen Rearrangement that Follows Carbomagnesiation
作者:Hiroto Yasui、Hideki Yorimitsu、Koichiro Oshima
DOI:10.1246/cl.2007.32
日期:2007.1
Treatment of N-allyl-N-(phenylethynyl)arenesulfonamides with Grignard reagents under copper catalysis resulted in carbomagnesiation across the alkynyl parts. The carbomagnesiations yielded 2-magnesio-3-aza-1,5-hexadienes, which underwent the aza-Claisen rearrangement upon heating. The rearrangement followed by elimination of the arenesulfonyl groups provided 2,2-disubstituted 4-pentenenitriles.
Silylcupration and Copper-Catalyzed Carbomagnesiation of Ynamides: Application to Aza-Claisen Rearrangement
作者:Hiroto Yasui、Hideki Yorimitsu、Koichiro Oshima
DOI:10.1246/bcsj.81.373
日期:2008.3.15
Treatment of ynamides with silylcopper reagents resulted in silylcupration to afford (E)-β-silylenamides, after protonolysis, in good yields with high regio- and stereoselectivity. Reaction of ynamides having an allyl group on the nitrogen with Grignard reagents in the presence of a copper catalyst resulted in carbomagnesiation across the alkynyl unit and subsequent heating provided 4-pentenenitriles via aza-Claisen rearrangement.