No abstract

An enamine-catalyzed strategy has been utilized to fully promote the Huisgen [3+2] cycloaddition with a broad spectrum of carbonyl compounds and azides, thereby permitting the efficient assembly of a vast pool of highly substituted 1,2,3-triazoles. In particular, the employment of commonly used and commercially available carbonyl compounds has resulted in the introduction of a diverse set of functional groups, such as alkyl, aryl, nitrile, ester, and ketone groups, at the 1-, 4-, or 5-positions of the 1,2,3-triazole scaffold. This approach might be manipulated to access more useful and sophisticated heterocyclic compounds. Most significantly, the reaction process exhibits complete regioselectivity, with the formation of only one regioisomer.

No abstract

An unprecedented enantioselective organocatalytic Michael/hemiketalization/retro-Henry cascade sequence is described, which catalyzed by a simple bifunctional indane amine-thiourea catalyst. This process provides a new route to the enantioselective synthesis of 5-nitro-pent-2-enoates, a precursor to α-ketolactam.

Efficient excess: An efficient and facile enantioselective Michael addition reaction through hydrogen‐bonding catalysis for the synthesis of coumarin complexes has been developed (see scheme). A simple bifunctional amine–thiourea small molecule has been discovered to catalyze this process with high yields and high to excellent enantiomeric excesses.