Catalyst-controlled divergent intermolecularcycloadditions of vinylaziridines with alkynes have been developed. By using [Rh(NBD)2]BF4 as the catalyst, a [3 + 2] cycloaddition reaction was achieved with broad substrate scope and high stereoselectivity under mild reaction conditions. Moreover, the chirality of vinylaziridines can be completely transferred to the [3 + 2] cycloadducts. When the catalyst
The highly efficient and stereo-specific synthesis of the enantioenriched versatile buildingblocks—namely, β-vinyltryptamines—by rhodium-catalyzed allylic substitutions of vinylaziridines and indoles is presented. Besides indoles, pyrroles can also serve as competent carbon nucleophiles in the current reaction, which is different from the previous works. To demonstrate the synthetic utility of our
The synthesis of γ-lactams is reported by a formal (3+2) cycloaddition between readily available ketenes and aziridines or a one-pot formal (2+1+2) cycloaddition using imines as aziridine precursors. The method is practical, is scalable, and affords high yields. It also offers a high level of regio- and diastereoselectivity on a wide range of substrates as well as a high stereoselectivity in the case
nitridomanganese complex as a nitrogen source. The reaction proceeded selectively and in good yield via [2+1] addition to give alkenylaziridines, with no evidence for the formation of any [4+1] addition products. The first asymmetric version of the reaction was revealed in the aziridination of diene 5 with chiral complex 1.
Divergent Access to Functionalized Pyrrolidines and Pyrrolines via Iridium-Catalyzed Domino-Ring-Opening Cyclization of Vinyl Aziridines with β-Ketocarbonyls
A useful synthesis of five-membered N-heterocycles has been developed through an iridium-catalyzed domino-ring-opening cyclization of vinylaziridines with β-ketocarbonyls. α-Substituted 1,3-dicarbonyls reacted with vinylaziridines to give 2-methylenepyrrolidines bearing two adjacent sp3-carbon centers with moderate to excellent diastereoselectivity, while the reaction of α-unsubstituted 1,3-dicarbonyls