Alkenyl halides, aziridine

Methods for the palladium-catalysed alkenylation of aziridines with alkenyl halides and copper-catalysed alkenylation of aziridines with alkenylboronic acids have been developed (Scheme 94).136... 

Hayashi S, Yorimitsu H, Oshima K (2009) Synthesis of aziridines by palladium-catalyzed reactions of allylamines with aryl and alkenyl halides evidence of a syn-carboamination pathway. Angew Chem 48 7224-7226. doi 10.1002/anie.200903178... 

V-Alkenyl aziridines 14 can be accessed through Pd(0)-mediated reaction of aziridines 12 with alkenyl halides 13. A wide variety of Al-alkenyl aziridines 14, containing many substituents, alkyl, aryl, ester, ketone, etc., may be synthesized in good yields (eq 14). 

A-Benzyl-2-methylaziridine with phenol and dimethylformamide at 60° formed (2S,55)-dimethyM,4-dibenzylpiperazine (1666), 1-cyclohexylaziridine with phenylmagnesium bromide gave 1,4-dicyclohexylpiperazine (1667), and some 1-alkylaziridines with alkyl, alkenyl, or benzyl halides, as well as with dialkylchloro-ethylamines, have been found to give nearly quantitative yields of the corresponding 1,1,4-trialkylpiperazinium halides (1668). Dimerization of dimethyl l-(p-methoxyphenyl)aziridine-2,3-dicarboxylate gave two isomers of 2,3,5,6-... 

Yudin and co-workers used aziridines as the amino partner in palladium-catalyzed alkenylations with vinyl halides developing thus a straightforward method for the synthesis of N-alkenyl aziridines (Scheme 19) [75]. They observed that copper catalysts provided comparatively lower 5delds, albeit allowed for the preparation of some aziridines inaccessible with a palladium catalyst. Due to the sensitivity of the coupling products toward aziridine ring opening on silica gel, the crude reactions had to be purified by either distillation or flash chromatography on alumina to ensure acceptable yields. 

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