Indirect Cation Pool Method. Rapid Generation of Alkoxycarbenium Ion Pools from Thioacetals
作者:Seiji Suga、Kouichi Matsumoto、Koji Ueoka、Jun-ichi Yoshida
DOI:10.1021/ja0625778
日期:2006.6.1
the electrochemical generation and accumulation of ArS(ArSSAr)+ at low temperature (step 1) and the follow-up reaction with a thioacetal to generate an alkoxycarbeniumion pool (step 2), which reacts with various carbonnucleophiles (step 3). Steps 2 and 3 are extremely fast. The electrogenerated ArS(ArSSAr)+ was well-characterized by 1H NMR and CSI-MS. The alkoxycarbeniumion pool generated by the
Indirect Cation-Flow Method: Flash Generation of Alkoxycarbenium Ions and Studies on the Stability of Glycosyl Cations
作者:Kodai Saito、Koji Ueoka、Kouichi Matsumoto、Seiji Suga、Toshiki Nokami、Jun-ichi Yoshida
DOI:10.1002/anie.201100854
日期:2011.5.23
Go with the flow: The indirect cation‐flow method based on the generation of highly reactive organic cations from their precursors using electrochemically generated [ArS(ArSSAr)]+ was developed in flow microreactor systems (see scheme; Bn=benzyl, M=micromixer, R=microtube reactor). The method was applied to evaluate glycosyl cations such as A or their equivalents and glycosylation reactions.
Methoxy(phenylthio)methane undergoes electrophilic alkylation followed by nucleophilic allylation or propargylation which is dramatically changed depending on the Lewis acid employed providing a methoxy- or phenylthiomethylene 1,1-dipole synthon.
Generation of Alkoxycarbenium Ion Pools from Thioacetals and Applications to Glycosylation Chemistry
作者:Shinkiti Suzuki、Kouichi Matsumoto、Kohsuke Kawamura、Seiji Suga、Jun-ichi Yoshida
DOI:10.1021/ol048524h
日期:2004.10.1
[reaction: see text] Alkoxycarbenium ions have been generated and accumulated as "cation pools" by the low-temperature electrochemical oxidation of alpha-phenylthioethers. Although an unsuccessful attempt to accumulate glycosyl cations was made, a one-pot method for electrochemicalglycosylation, which involves anodic oxidation of thioglycosides to generate glycosyl cation equivalents followed by their reactions