Chiral Brønsted acid catalyzed enantioselective syntheses of isoindolinones and phthalides have been accomplished via tandem Mannich-lactamization and aldol-lactonization reactions, respectively. A variety of enantioenriched isoindolinones (up to 99% ee) and phthalides (up to 85% ee) containing α-diazoesters were afforded in excellent yields. Furthermore, a concise synthesis of (S)-PD 172938 has been demonstrated by using this protocol.

A chiral phosphoric acid-catalyzed asymmetric Mannich-type reaction of α-diazo esters with in situ generated N-acyl ketimines, derived from 3-hydroxyisoindolinones has been demonstrated in this communication. A variety of isoindolinone-based α-amino diazo esters bearing a quaternary stereogenic center were afforded in high yields (up to 99%) with excellent enantioselectivities (up to 99% ee). Furthermore, the synthetic utility of the products has been depicted by the hydrogenation of the diazo moiety of adducts.

An efficient diastereo- and enantioselective route to access a wide range of highly substituted pyrrolidine and pyrrolizidine derivatives has been described via (1,3)- and double (1,3)-dipolar cycloaddition reactions catalyzed by the (R)-DM-SEGPHOS-Ag(I) complex. The reactions proceed smoothly at ambient temperature, affording a variety of pyrrolidines and pyrrolizidines in high yields (up to 93%) with up to 99:1 dr and excellent enantioselectivities (up to 98% ee) without any additives. The newly synthesized pyrrolidine and pyrrolizidine derivatives contain four and seven contiguous stereogenic centers, respectively. Moreover, the synthetic utility of enantioenriched products has been demonstrated by transforming them into various synthetically useful advanced intermediates.

Quinine derived bifunctional urea catalyzed cascade Michael-acyl transfer reaction of 5-alkenyl thiazolones and monofluorinated β-diketones has been developed. The fluorine containing 4-acyloxy thiazoles were synthesized in high yields and good diastereo-and excellent enantioselectivities. Synthetic transformations, including synthesis of 4-hydroxy thiazoles, have been demonstrated.

An efficient route to enantioenriched propargylamines via a three-component alkynylation reaction using cooperative catalysis with a CuI- i PrpyboxdiPh complex and N-Boc-(l)-proline has been accomplished. A variety of functionalized amines, aldehydes, and 2-ethynyl anilines were reacted smoothly at ambient temperature to furnish a wide range of propargylamines in high yields (up to 94%) and excellent enantioselectivities (up to 98% ee). Synthetic utility of the methodology has been demonstrated by transforming the products into various synthetically useful intermediates. Finally, propargylamines were transformed into biologically important (indol-2-yl)­methanamines over two steps in good yields (up to 88%) with an excellent level of enantioselectivities (up to 95%).