N-heterocyclic carbene catalyzed synthesis of oxime esters.

N-Heterocyclic carbene-catalyzed direct cross-aza-benzoin reaction: Efficient synthesis of α-amino-β-keto esters

An efficient catalytic synthesis of α-amino-β-keto esters has been newly developed. Cross-coupling of various aldehydes with α-imino ester, catalyzed by N-heterocyclic carbene, leads chemoselectively to α-amino-β-keto esters in moderate to good yields with high atom efficiency. The reaction mechanism is discussed, and it is proposed that the α-amino-β-keto esters are formed under thermodynamic ...

Catalytic dynamic kinetic resolutions with N-heterocyclic carbenes: asymmetric synthesis of highly substituted β-lactones.

New DKR type: An N-heterocyclic carbene (NHC)-catalyzed dynamic kinetic resolution of racemic α-substituted β-keto esters has been developed. This method relies on the epimerization of an NHC-enol intermediate before subsequent aldol/acylation events. Highly substituted β-lactones are produced in good yield with good to excellent selectivities (see scheme).

N-heterocyclic-carbene-catalyzed one-pot synthesis of hydroxamic esters.

N-heterocyclic-carbene-catalyzed asymmetric oxidative hetero-Diels-Alder reactions with simple aliphatic aldehydes.

N-heterocyclic carbene (NHC) catalysis has emerged as a powerful tool for synthesis. Among its involvement in several cycloaddition-type reactions for the construction of lactams and lactones, which are abundant in biologically active molecules and broadly used as synthons for complex molecules, NHC catalysis through formal [3+3] or [4+2] strategies is noteworthy. In particular, [4+2] cycloaddi...

N-heterocyclic carbene catalyzed annulation of benzofuran-2,3-diones and enals: a concise synthesis of spiro-bis-lactone.

The N-heterocyclic carbene catalyzed annulation of benzofuran-2,3-diones and enals via homoenolate intermediates is described. The reaction provided a direct and efficient method for the synthesis of spiro-bis-lactones. The ketone-carbonyl group annulated products and the ester-carbonyl group annulated products can be obtained as major products with good yields by convenient catalyst regulation...