Unexpected synthesis of aziridines under Cu(I) catalyzed Kinugasa conditions assisted by microwave irradiation

Abstract

a b s t r a c tCu(I)-catalyzed 1,3-dipolar cycloaddition between chiral nitrone and terminal alkynes under microwave irradiation afforded a series of enantiopure aziridines with the creation of two contiguous stereogenic centers.

Recent Advances in Microwave-Assisted Copper-Catalyzed Cross-Coupling Reactions

“…Copper or its salts as catalyst under microwave irradiation has been extensively studied for the construction of heterocyclic systems. For examples, 3,5-disubstituted isoxazoles from the natural maslinic and oleanolic acids [82], 1,2-disubstituted indoles from α-aminonitriles and 2-halobenzyl halides [83], 3,3-disubstituted oxindoles from oxidative cyclization of acrylamide derivatives with non-activated ketones [84], substituted pyrroles via tandem copper-catalyzed propargylation/alkyne azacyclization/isomerization reaction [85], aziridines through Kinugasa conditions [86], fused imidazo heterocycles via multi-component reaction [87], 5-alkylamino-1H-pyrazole-4-carbaldehydes [88], 3,4diaryl isoquinolines using N-tert-butyl-o-iodobenzaldimine, phenylacetylene and iodobenzene as starting materials [89], pyrimidinones from the coupling and cyclization of βbromo-α,β-unsaturated amides with amidine hydrochlorides [90,91], pyrimidinones using three component Biginelli reaction [92], 3-N-sulfonylamidine coumarins via four component coupling reaction [93], 2H-pyran-2-ones from the cycloaddition of β-bromo-α,βunsaturated carboxylic acids with 1,3-diketones [94], furoquinoxalines from 2-amino substituted anilines, ethyl glyoxalate, and terminal alkynes through tandem A 3 coupling followed by a 5-endo-dig cyclization process [95], 5,6-dihydroindolo[1,2-a]quinoxaline derivatives via intramolecular N-arylation [96], isoquinolines and pyridines under multicomponent reaction of β-halovinyl/aryl aldehyde, aromatic/aliphatic terminal alkyne and tert-butylamine/benzamidine [97] and from o-bromoarylaldehydes, terminal alkynes, and aqueous ammonia [98], 2-aminooxazolo [4,5-b] pyridines through intramolecular C-O bond formation in aqueous medium [99], chiral nopinane-annelated pyridines from the reaction of pinocarvone oxime with enamines [100], dihydropyridines from substituted aromatic aldehydes using Hantzsch synthesis [101], pyrazole-based heterocycles via domino annulation [102], 2,6-diaminopyridines through amination of halopyridines [103], pyrazoles via N-arylation [104], phenylethynyl[1,2,4]methyltriazines from the cross coupling of 5-methyl-3-methyl-thio [1,2,…”

The Baldwin Rearrangement: Synthesis of 2‐Acylaziridines

“…The one‐pot acylaziridination of (–)‐menthone‐based imidazolinyl nitrone 52 in the presence of CuI and triethylamine was reported by Aouadi and co‐workers (Scheme ) . The reaction proceeded in acetonitrile or DMF, on heating at 100 °C under microwave irradiation conditions.…”