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A novel and efficient palladium‐catalyzed regioselective and stereodivergent ring‐closing reaction of aminoenynes with aldehydes and boronic acids or hydrosilane is developed. This three‐component reaction allows for the modular synthesis of a series of exocyclic 1,3‐dienes bearing 5‐ to 8‐membered saturated N‐heterocycles. The reactions utilize a simple Pd‐catalyst and work with broad range of aminoenynes, aldehydes and organometallic reagents under mild reaction conditions. The products represent useful intermediates for chemical synthesis due to the versatility of the conjugated diene. Preliminary mechanistic details of the method are also revealed. [ABSTRACT FROM AUTHOR]

An efficient strategy for preventing the β‐hydride elimination of alkylpalladium species by ligation of the palladium with adjacent amino‐group was developed, which enabled a novel palladium‐catalyzed ring‐closing aminoalkylative amination of unactivated aminoenynes. The reaction is amenable to aminals, as well as aliphatic aldehydes with secondary amines, which provides straightforward access to structurally diverse exocyclic allenic amines bearing 5 to 12‐membered N‐heterocycles. With chiral phosphoramidite‐ligated palladium complex as the catalyst, an enantioselective variant was achieved with up to 93 % ee. Simultaneously, synthetic transformations of the chiral products were also conducted to afford structurally unique spirodiamines including one pharmaceutically active molecule via axial‐to‐central chirality transfer. [ABSTRACT FROM AUTHOR]