β-Turn tetrapeptides were demonstrated to catalyze asymmetric aldol reaction of α-branched aldehydes and α-carbonyl aldehydes, i.e. glyoxylates and α-ketoaldehydes, to biomimetically synthesize acyclic all-carbon quaternary center-bearing 1,4-dicarbonyls in high yield and excellent enantioselectivity under mild conditions. The spatially restricted environment of the tetrapeptide warrants high enantioselectivity and yield with broad substrates. Using this protocol, (R)-pantolactone, the key intermediate of vitamin B5, was readily accessed in a practical, efficient, and environmentally benign process from inexpensive starting materials.

The enantioselective cross-aldol reaction between o-hydroxyacetophenones and trifluoromethyl ketones catalyzed by chiral thiourea organocatalysts is reported. Gram-scale synthesis of the cross-aldol product was carried out, with no decrease in the yield and enantioselectivity. Furthermore, the cross-aldol products thus prepared were used in the preparation of medicinally interesting 3,5-diaryl-5-trifluoromethyl-2-isoxazoline and β-trifluoromethyl-β-tertiary hydroxy acid ester with high yield and enantiopurity.

Transition‐metal‐catalyzed C−H functionalization of aromatic secondary amides with alkynes mainly undergo C−H/N−H annulation but rarely undergo ortho‐alkenylation. It is particularly challenging to selectively realize both oxidative annulation and ortho‐alkenylation of aromatic secondary amides with alkynes in the transition‐metal‐catalysis. In this article, we synthesized fully‐substituted 2‐pyridones and 2,6‐naphthyridine‐1,5‐diones via C(sp2)−H functionalization of fumaramides for the first time. Under the Ru‐catalysis, fumaramides and 1,2‐diaryl ethynes first undergo C−H/N−H annulation leading to the intermediate 2‐pyridone with an exocyclic secondary amide, and subsequently undergo the unexpected stereoselective C−H alkenylation to realize fully substituted 2‐pyridones bearing an exocyclic anti alkenyl group. On the addition of K2CO3, however, the transformation of fumaramides with 1,2‐dialkyl ethyne undergoes two conventional C−H/N−H annulations to provide 2,6‐naphthyridine‐1,5‐diones in high yield. The two procedures can be successfully enlarged to gram‐scales without erosion of the yields. In addition, some 2‐pyridones and 2,6‐naphthyridine‐1,5‐diones emitting clear ultraviolent and fluorescent light, indicating the potential utility of this work in organic light‐emitting materials.

The highly asymmetric Michael addition reaction between maleimides and aliphatic aldehydes catalyzed by low-loading β-turn tetrapeptides with excellent yield and enantioselectivity at room temperature was reported. α-Branched and α-unbranched aldehydes...