Difluoroacetaldehyde
<i>N</i>
‐Triftosylhydrazone (DFHZ‐Tfs) as a Bench‐Stable Crystalline Diazo Surrogate for Diazoacetaldehyde and Difluorodiazoethane
study, we developed a bench-stable difluoroacetaldehyde N-triftosylhydrazone (DFHZ-Tfs) as an operationally safe diazo surrogate that can release in situ two low-molecular-weight diazoalkanes, diazoacetaldehyde (CHOCHN2 ) or difluorodiazoethane (CF2 HCHN2 ), in a controlled fashion under specific conditions. DFHZ-Tfs has been successfully employed in the Fe-catalyzed cyclopropanation and Doyle-Kirmse
3-allyl/3-allenyl-3-(thio)oxindole core remains a challenge in organic synthesis. Herein, we report a novel Rh2(esp)2 catalytic Doyle–Kirmse reaction to furnish the oxindole core, bearing unbiased NH as well as a quaternary stereogenic center at the 3-position, in good to excellent yields under mild conditions. These reactions are concise, practical, atom-economic, and highly efficient, and feature a TON
Rh-Catalyzed [2,3]-Sigmatropic Rearrangement of Alkynyl Carbenes with Allyl Sulfides to Access Sulfide-Substituted 1,5-Enynes
作者:Zhongxue Fang、Yu Wang、Yiming Ma、Xinyue Han、Zhaohong Liu、Yongquan Ning
DOI:10.1021/acs.joc.2c02910
日期:2023.7.21
describes the development of Rh-catalyzed [2,3]-sigmatropicrearrangement of alkynyl carbenes with allyl sulfides. The protocol exhibits equitable functional group tolerance and allows the formation of a variety of synthetically valuable sulfide-substituted 1,5-enyne products. To the best of our knowledge, this is the first example of [2,3]-sigmatropicrearrangement of alkynyl carbenes. DFT analysis supports