A direct and facile access to enantioenriched pyroglutamate derivatives bearing a unique quaternary stereogenic center has been developed via Cu(I)/BINAP-catalyzed tandem Michael addition-elimination of α-substituted aldimino esters with Morita-Baylis-Hillman (MBH) carbonates followed by a deprotection/lactamization protocol, which performs well over a broad scope of substrates and provides biologically active pyroglutamate derivatives in good yields and excellent enantioselectivities.

A Facile Cu(I)/BINAP-Catalyzed Asymmetric Approach to Functionalized Pyroglutamate Derivatives Bearing a Unique Quaternary Stereogenic Center. -The tandem Micheal addition-elimination [ -> conditions A)] is followed by deprotection [-> conditions B)] and lactamization [-> conditions C)]. In most cases, the pharmacologically important products are formed as single (E) isomers. -(TENG, H.-L.; LUO, F.-L.; TAO, H.-Y.; WANG*, C.-J.; Org. Lett. 13 (2011) 20, 5600-5603, http://dx.doi.org/10.1021/ol202326j ; Coll. Chem. Mol. Sci., Wuhan Univ., Wuhan, Hubei 430072, Peop. Rep. China; Eng.) -H. Simon 07-193