Visible light-induced N-radical 5-exo/6-endo cyclization of alkenyl amides: facile access to isoindolinones/isoquinolinones

Abstract

An efficient N-centered radicals intramolecular cyclization reaction of alkenyl amide induced by visible light was described. In this process, alkenyl amide underwent 5-exo/6-endo cyclization to selectively synthesize two critical alkaloid...

Transition-Metal-Free Selective Halocyclization of N-Alkoxy Amides: Synthesis of N-Alkoxy Lactams and Oximinolactones

“…Starting materials amides 1-allyl-N-methoxycyclobutanecarboxamide (1a), 1-allyl-N-methoxycyclohexanecarboxamide (1b), N-methoxy-2,2-dimethylpent-4-enamide (1c), 2-ethyl-N-methoxy-2methylpent-4-enamide (1d), 2-allyl-N-methoxy-2-methylpent-4enamide (1f), and N-methoxy-2-vinylbenzamide (1m) were synthesized by using a known literature method, 18 as were N-methoxy-2,2diphenylpent-4-enamide (1e), 1-allyl-N-ethoxycyclohexanecarboxamide (1h), 19 N-methoxypent-4-enamide (1g), 5i N-ethoxypent-4enamide (1u), 20 N-(benzyloxy)pent-4-enamide (1v), 5a N-methoxy-2,2-diphenylhex-5-enamide (1w), 21 (E)-N-methoxy-2,2-diphenylhex-4-enamide (1q), 22 N,5-dimethoxy-2-vinylbenzamide (1y), 5b N-methoxy-2-phenylpent-4-enamide (1z). 5b Starting material for the synthesis of 2g N-methoxy-2-methyl-pent-4-enamide (1n) 5i .…”

Photocatalytic Intramolecular Alkene Hydroamination of N-Alkoxy Ureas: An Approach to Imidazolinones

“…Recently, our group devised a new protocol using N -alkoxy amides as precursors to generate amidyl radicals through visible light catalysis, applying it to intramolecular alkene hydroamination reactions for the mild synthesis of isoindolinones and isoquinolinones . The difference between N -alkoxy amides and N -aryl/ N -alkyl amides is that the adjacent oxygen weakens the N–H bond and lowers the energy required to dissociate the N–H bond (BDE of N–H = 90 kcal/mol).…”