ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Synthesis of some derivatives of alkaloids. XVIII

K. Babor, I. Ježo, V. Kaláč, M. Karvaš, and K. Tihlárik

Slovak Academy of Sciences, Bratislava

Abstract: cf. CA 54, 22698f. Synthesis of dl-1-hydroxymethyl-7-hydroxypyrrolizidine, identical with platynecine, was described. SOCl₂ with 2-hydroxy-3-methoxybutyronitrile, b18 133°, n20D 1.4365, formed 2-chloro-3-methoxybutyronitrile, b9 90°, n20D 1.4439, d20 1.1287, which by condensation with di-Et sodiomalonate via di-Et (1-methoxy-3-cyanoisopropyl)malonate, b9 170-2°, n20D 1.4410, d20 1.087, could be catalytically hydrogenated either to Et 5-amino-3-methoxymethyl-2-carbethoxyvalerate (under pressure with PtO₂ at room temp.) or 4-methoxymethyl-3-carbethoxy-2-piperidone (with Raney Ni at 120-30°/80 atm. initial pressure), b2 178-84°, n22D 1.4830. Both compds. after alkali hydrolysis and benzoylation (Schotten - Baumann) with 3,5-dinitrobenzoyl chloride formed 5-(3,5-dinitrobenzoylamino)-3-methoxymethyl-2-carboxyvaleric acid, m. 151-2°, which either by bromination or by thermal decarboxylation was changed into 2-carbethoxy-3-methoxymethylpyrrolidine (I), b16 118-20°, n20D 1.4585, d20 1.055. In glacial HOAc viscous oily 5-(3,5-dinitrobenzoylamino)-3-methoxymethyl-2-bromo-2-carboxyvaleric acid formed, which after intramol. cyclization with alkali formed N-(3,5-dinitrobenzoyl)-2,2-dicarboxy-3-methoxymethylpyrrolidine (not isolated), acid hydrolyzed and esterified to give I. 5-(3,5-Dinitrobenzoylamino)-3-methoxymethylvaleric acid, m. 131-2°, by bromination in the presence of red P formed 5-(3,5-dinitrobenzoylamino)-3-methoxymethyl-2-bromovaleric acid, m. 192°, which after intermol. cyclization gave N-(3,5-dinitrobenzoyl)-2-carboxy-3-methoxymethylpyrrolidine (not isolated), acid hydrolyzed and esterified to give I. Michael addn. of Et acrylate to I gave Et 3-(3-methoxymethyl-2-carbethoxypyrrolidino)propionate, b0.05 132-5°, b1 160-5°, n20D 1.4573, d20 1.059, which after Dieckmann condensation gave 1-methoxymethyl-6-carbethoxy-7-oxopyrrolizidine (not isolated), decarboxylated to 1-hydroxymethyl-7-oxopyrrolizidine, n20D 1.4400, d20 1.093, catalytically hydrogenated to dl-1-hydroxymethyl-7-hydroxypyrrolizidine, m. 138-41° (acetone); picrate m. 176-8° (EtOH); MeI salt m. 200-2° (EtOH).

Full paper in Portable Document Format: 1410a679.pdf (in Slovak)

Chemical Papers 14 (10) 679–689 (1960)