Tertiary amine-promoted enone aziridination: investigations into factors influencing enantioselective induction

3-Arylaziridine-2-carboxylic Acid Derivatives and (3-Arylaziridin-2-yl)ketones: The Aziridination Approaches

“…Finally, Armstrong’s aziridination must be noted as a remarkable advance in the direct access to 3-arylated N-unsubstituted aziridin-2-yl ketones trans - 1c10 ( Scheme 48 ) and carboxylates trans - 1a15. Armstrong’s aziridination implies the use of N,N-ylides generated from N-methylmorpholine, or other tertiary amines in the presence of Ph 2 P(O)ONH 2 (dppONH 2 ) as NH transfer agent ( Scheme 48 ) [ 139 , 140 , 141 ].…”

“…The yields were 32-97%; higher yields were obtained by chalcones 29c. Enantioselective variation of this process using quinine as tertiary amine (yields 35-68% and 37-56% ee, eight examples) [140] and aziridination of highly functionalized Scheme 47. Hydroxylamine reagent-mediated aziridination products [137,138].…”

“…The yields were 32-97%; higher yields were obtained by chalcones 29c. Enantioselective variation of this process using quinine as tertiary amine (yields 35-68% and 37-56% ee, eight examples) [140] and aziridination of highly functionalized alkyl arylidene ketones 29c (Scheme 48) (yields 51-81%) has been reported [141]. In the initial work [139], chalcones and cinnamates 29a, c were successfully aziridinated to obtain trans-aziridine-2-ketones 1c10 and carboxylates trans-1a15 (Scheme 48)…”

Recent Developments in Asymmetric Aziridination

“…[101] As shown in Scheme 64, the corresponding trans-aziridines were synthesized in moderate yields (27-47%) and enantioselectivities of up to 77% ee. [101] As shown in Scheme 64, the corresponding trans-aziridines were synthesized in moderate yields (27-47%) and enantioselectivities of up to 77% ee.…”

“…In 2014, Armstrong et al. described the asymmetric aziridination of heteroaromatic‐substituted enones with diphenylphosphinylhydroxylamine mediated by another Cinchona alkaloid catalyst such as quinine, employed in stoichiometric quantity 101. As shown in Scheme , the corresponding trans‐ aziridines were synthesized in moderate yields (27–47%) and enantioselectivities of up to 77% ee .…”