N-Methylconiine is a poisonous alkaloid found in poison hemlock in small quantities.
Isolation and properties The -(+)-stereoisomer of N-methylconiine is reported to occur in hemlock in small quantities,Planta and Kekulé, Annalen, 1854, 89, 150. and methods for its isolation are described by WolffensteinBer., 1894, 27, 2615; 1895, 28, 302 and by von Braun.Ber., 1905, 38, 3108; 1917, 50, 1477. It is a colourless, oily, coniine-like liquid, specific rotation [α]D +81.33° at 24.3 °C. The salts are crystalline ("B" marks one molecule of the base): the hydrochloride, B•HCl, forms masses of needles, mp. 188 °C; the platinichloride, B2•H2PtCl6, has mp. 158 °C.
The -(−)-stereoisomer was obtained by AhrensBer., 1902, 35, 1330; cf. Löffler and Friedrich, ibid., 1909, 42, 107. from residues left in the isolation of coniine as hydrobromide or by removing coniine as the nitroso-compound. It is a colourless, coniine-like liquid, bp. 175.6 °C/767 mmHg, specific rotation [α]D −81.92° at 20 °C. The monohydrochloride crystallises in leaflets, mp. 191–192 °C; the monohydrobromide in leaflets, mp. 189–190 °C; the platinichloride in orange crystals, mp. 153–154 °C; the aurichloride in leaflets, mp. 77–78 °C; and the picrate in long needles, mp. 121–122 °C.
Synthesis N-Methyl--coniine was prepared by the action of potassium methyl sulfate on coniine by Passon.Ber., 1891, 24, 1678. Hess and EichelBer., 1917, 50, 1386; 1919, 52, 1622; 1920, 53, 129. have shown that -coniine with formaldehyde and formic acid yields an active N-methyl--coniine, and that methyl-isopelletierine hydrazone yields N-methyl--coniine when heated with sodium ethoxide at 150–170 °C.
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