AbstractCopper(II) acetylacetonate‐catalyzed Wittig olefination reactions of aldehydes with ketone‐derived N‐tosylhydrazones are reported. A series of tosylhydrazones was investigated and our results showed that the carbon number of the alkyl chain influences the E‐selecivity of the alkenes greatly. Alkenes could be obtained in moderate yields and excellent E‐selectivity when the carbon numbers were up to two. Under metal‐free conditions, triphenylphosphine was able to capture the in situ generated diazo compounds and the corresponding unsymmetrical azines were formed in good yields.magnified image
Pd-Catalyzed Alkenyl Thioether Synthesis from Thioesters and <i>N</i>-Tosylhydrazones
作者:Kota Ishitobi、Kei Muto、Junichiro Yamaguchi
DOI:10.1021/acscatal.9b04212
日期:2019.12.6
A Pd-catalyzed alkenyl thioethersynthesis was achieved using thioesters and N-tosylhydrazones as starting materials. The thioester acted as an efficient “sulfur source” for catalytic C–S bond formation using N-tosylhydrazone. This method gave Z-alkenyl thioethers with high diastereoselectivity (up to 99:1 diastereomeric ratio). This transformation displayed a wide functional group tolerance and was