485809-15-2Relevant academic research and scientific papers
Catalytic asymmetric epoxidation of α,β-unsaturated amides: Efficient synthesis of β-aryl α-hydroxy amides using a one-pot tandem catalytic asymmetric epoxidation - Pd-catalyzed epoxide opening process
Nemoto, Tetsuhiro,Kakei, Hiroyuki,Gnanadesikan, Vijay,Tosaki, Shin-Ya,Ohshima, Takashi,Shibasaki, Masakatsu
, p. 14544 - 14545 (2002)
The catalytic asymmetric epoxidation of α,β-unsaturated amides using Sm-BINOL-Ph3As=O complex was succeeded. Using 5-10 mol % of the asymmetric catalyst, a variety of amides were epoxidized efficiently, yielding the corresponding α,β-epoxy amides in up to 99% yield and in more than 99% ee. Moreover, the novel one-pot tandem process, one-pot tandem catalytic asymmetric epoxidation-Pd-catalyzed epoxide opening process, was developed. This method was successfully utilized for the efficient synthesis of β-aryl α-hydroxy amides, including β-aryllactyl-leucine methyl esters. Interestingly, it was found that beneficial modifications on the Pd catalyst were achieved by the constituents of the first epoxidation, producing a more suitable catalyst for the Pd-catalyzed epoxide opening reaction in terms of chemoselectivity. Copyright
