Novel synthesis of lactam from alkyne having amide in a tether using fischer chromium carbene complex

Ochifuji, Nagisa; Mori, Miwako

doi:10.1016/0040-4039(95)02058-6

Cited by 10 publications

(3 citation statements)

References 8 publications

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“…The combined organic layers were dried with MgSO 4 and concentrated in vacuo. The residue was purified by column chromatography (hexanes/EtOAc 1:0→3:2) to afford sulfonamide 18 as a colorless solid (12.6 g, 85%): mp 63−65 °C; 1 H NMR (500 MHz, CDCl 3 ) δ 7.75 (d, J = 8.5 Hz, 2H), 7.30 (d, J = 8 Hz, 2H), 4.95−4.88 (m, 1H), 2.94 (q, J = 6.5 Hz, 2H), 2.42 (s, 3H), 2.15−2.12 (m, 2H), 1.91 (t, J = 2.5 Hz, 1H), 1.61−1.55 (m, 2H), 1.51−1.47 (m, 2H) ppm; 13 C NMR (125 MHz, CDCl 3 ) δ 143.5, 137.1, 129.9, 127.2, 83.9, 69.0, 42.8, 28.6, 25.4, 21.7, 18.0 ppm; IR (thin film) 3294, 2944, 2870, 1598, 1426, 1322, 1154, 1092 cm −1 ; HRMS (ESI) m / z 274.0871 (274.0878 calcd for C 13 H 17 NO 2 SNa + [MNa] + ).…”

Section: Methodsmentioning

confidence: 99%

Total Synthesis of (+)-Nankakurines A and B and (±)-5-epi-Nankakurine A

et al. 2010

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The first total syntheses of the Lycopodium alkaloids (+)-nankakurine A (2), (+)-nankakurine B (3) and the originally purported structure 1 of nankakurine A were accomplished. The syntheses of 2 and 3 feature a demanding intramolecular azomethine imine cycloaddition as the key step for generating the octahydro-3,5-ethanoquinoline moiety and installing the correct relative configuration at the spiro piperidine ring juncture. The cyclization precursor was prepared from octahydronaphthalene ketone 50, which was assembled from enone (+)-9 and diene 48 by a cationic Diels–Alder reaction. The Diels–Alder reactants were synthesized from 5-hexyn-1-ol (16) and (+)-pulegone (49), respectively. The tetracyclic ring system of 1 was generated using an unprecedented nitrogen-terminated aza-Prins cyclization cascade. The enantioselective total syntheses of (+)-nankakurine A (2) and (+)-nankakurine B (3) establish the relative and absolute configuration of these alkaloids, and are sufficiently concise that substantial quantities of 2 and 3 were prepared for biological studies. (+)-Nankakurine A and (+)-nankakurine B showed no effect on neurite outgrowth in rat hippocampal H-19 cells over a concentration range of 0.3–10 μM.

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Section: Methodsmentioning

confidence: 99%

Total Synthesis of (+)-Nankakurines A and B and (±)-5-epi-Nankakurine A

et al. 2010

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“…64 The reaction proceeds via a vinylketene complex A, generated from the alkyne and the Fisher chromium carbene complex, and the lactam ring was formed from carbon monoxide, alkyne, and the tosylamide nitrogen atom. The four-, five-, six-, and seven-membered lactams 112a-d having a substituent at the a-position were obtained in good yields (Scheme 47).…”

Section: Formation Of Substituted Lactamsmentioning

confidence: 99%

Synthesis of heterocycles by carbonylation of acetylenic compounds

et al. 2004

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“…From A lkynylamines. More interestingly, Mori et al have reported the synthesis of five- to seven-membered lactams 169 by reaction of alkynylamines 168 with the carbene complex 118 (Scheme ) . The process is invoked to begin with an alkyne insertion and evolves through a CO insertion followed by intramolecular nucleophilic nitrogen attack to the ketene intermediate.…”

Section: 22 From Nitrogen-containing Organic Substratesmentioning

confidence: 99%