Method for the Direct Enantioselective Synthesis of Chiral Primary α-Amino Ketones by Catalytic α-Amination
作者:Yixin Han、E. J. Corey
DOI:10.1021/acs.orglett.8b03733
日期:2019.1.4
A useful catalytic enantioselective approach has been developed for the synthesis of chiral ketamine analogs using Rh(II)-catalyzed amination of triisopropylsilyl enol ethers to form α-amino ketones with O-(4-nitrophenyl)hydroxylamine as nitrogen donor in 81–91% ee.
Asymmetric Diels-Alder reaction of the N-dienyl-L-pyroglutamic esters 1a-h with acyl nitroso dienophiles 4a-h gave diastereoisomeric adducts 6a-n, 7a-n with 12–90 % de, depending on solvents and temperature. An interpretation was gived. The “allylic effect” ( MO interactions) was found to be effective to account for the conformations of the adducts.