Divergent Protosilylation and Protoborylation of Polar Enynes

Copper-catalyzed divergent conjugate protosilylation and protoborylation of polar enynes were developed. The corresponding β-boryldienoates and β-silyldienotes were obtained in moderate to good yields and with good stereoselectivity. In this protocol, novel cascade double protoborylation/protodeboronation processes of polar enynoates enabled access of the useful trisubstituted vinylboronates in up to 80% yield and with up to 98:2 Z/E ratio. Moreover, divergent transformations of the products thus obtained were also investigated.

Palladium-Catalyzed Regioselective Olefination of O-Acetyl Cyanohydrins

A practical palladium-catalyzed ortho-olefination of O-acetyl cyanohydrins assisted by synergetic directing groups has been developed. Thus, a range of olefinated O-acetyl cyanohydrins were synthesized in moderate to good yields. The reaction occurs efficiently with high regioselectivity and with a satisfactory tolerance of functional groups.

Copper-Catalyzed Dehydrogenative Diels–Alder Reaction

A practical and effective copper-catalyzed dehydrogenative Diels−Alder reaction of gem-diesters and ketone with dienes has been established. The active dienophiles were generated in situ via a radical-based dehydrogenation process, which reacted with a wide variety of dienes to afford various polysubstituted cyclohexene derivatives in good to excellent yields.

Chelation versus Non-Chelation Control in the Stereoselective Alkenyl sp2 C−H Bond Functionalization Reaction

Palladium-Catalyzed Direct Intramolecular C–N Bond Formation: Access to Multisubstituted Dihydropyrroles

A palladium-catalyzed intramolecular amination of alkenes with retention of olefin functionalization was achieved under mild reaction conditions. In the presence of palladium catalyst, the tosyl-protected amine can directly couple with a double bond to provide versatile dihydropyrrole derivatives in moderate to excellent yields.

Macrolide Synthesis through Intramolecular Oxidative Cross-Coupling of Alkenes

A RhIII‐catalyzed intramolecular oxidative cross‐coupling between double bonds for the synthesis of macrolides is described. Under the optimized reaction conditions, macrocycles containing a diene moiety can be formed in reasonable yields and with excellent chemo‐ and stereoselectivity. This method provides an efficient approach to synthesize macrocyclic compounds containing a 1,3‐conjugated diene structure.

B(C6F5)3: A New Class of Strong and Bulky Lewis Acid for Exo-Selective Intermolecular Diels–Alder Reactions of Unreactive Acyclic Dienes with α,β-Enals

Lewis acid B(C6F5)3 catalyzed the Diels–Alder reactions of multisubstituted open-chain dienes and α,β-enals to afford the desired products with high exo-selectivities are reported. The substituent effect of the dienes and dienophiles on the product’s stereoselectivity was thoroughly investigated, and it was found that most of the desired exo-Diels–Alder products could be obtained in good yields and with high exo-stereoselectivities.