Diastereoselective and Enantioselective Synthesis of Unsymmetric beta,beta-Diaryl-alpha-Amino Acid Esters via Organocatalytic 1,6-Conjugate Addition of para-Quinone Methides

A novel strategy based on phase transfer catalysis for the diastereoselective and enantioselective direct assembly of unsymmetric beta,beta-diaryl-alpha-amino acid esters via 1,6-conjugate addition of para-quinone methides and glycine derivatives is described. This protocol also provides an alternative route to the synthetically interesting functionalized chiral tetrahydroisoquinoline and its analogues.National Natural Science Foundation of China [21572083, 21322201, 21290180]; Fundamental Research Funds for the Central Universities [lzujbky-2015-48]; State Key Laboratory of Natural and Biomimetic Drugs [K20150213]; PCSIRT [IRT_15R28]; 111 Project of Ministry of Education of China [111-2-17]; Chang Jiang Scholars ProgramSCI(E)EIARTICLEfanchunan@lzu.edu.cn135655-56628