Methylpyrrolinium cation

Sun, J. MacFarlane, D. R. Forsyth, M. A new family of ionic liquids based on the l-alkyl-2-methylpyrrolinium cation, Electrochim. Acta, 2003, 48(12), 1707-1711 Fors3dh, S. Golding, J. MacFarlane, D. R. Forsyth, M. A-methyl-iV-alkylpyrrolidinium tetrafluoroborate salts ionic solvents and solid electrolytes, Electrochim. Acta, 2001, 46(10-11), 1753-1757 Golding, J. J. Macfarlane, D. R. Spiccia, L. et al. Weak intermolecular interactions in sulfonamide salts structure of 1-ethyl-2-methyl-3-benzylimidazolium bis[(trifluoromethyl)sulfonyl]amide, Chem. Commun., 1998, 1593-1594. 

This allows an aldol-type reaction with the A-methylpyrrolinium cation, and finally dehydrogenation of the dihydropyridine ring back to a pyridine gives nicotine. Nornicotine is derived by oxidative demethylation of nicotine. Anaba-sine is produced from nicotinic acid and lysine via the A1 -piperidinium cation in an essentially analogous manner (Figure 6.32). A subtle anomaly has been exposed in that a further Nicotiana alkaloid anatabine appears to be derived by... 

A-methylputrescine oxidase catalyzes the formation of N-methylpyrrolinium cation, an important intermediate of tropane alkaloids biosynthetic pathway as well as of nicotine. Fig. (1). The... 

The subsequent reactions leading from 7V-methylpyrrolinium to tropinone remain doubtful since no enzymes have yet been demonstrated. For a long time, it was believed that the formation of the tropane ring from the jV-methyl-A -pyrrolinium cation occurred by condensation with an acetoacetyl unit, with the release of CO2, to form hygrine. This was... 

Photocyclizations of we a-(OH, OMe, OSiBu Mc2, CH3, CH2SiBu Mc2 and CHjSiMcs) substituted 7V-benzyl-2-methylpyrrolinium perchlorates proceed mainly or exclusively by cation.dirad-ical coupling mechanisms and afford the corresponding benzopyrrolizidines in modest t excellent yields <90JA3594>. 

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