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NICOTINE, C10H
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See also:NICOTINE, C10H ,4N2, an See also:alkaloid, found with small quantities of nicotimine, C19H,4N2, nicoteine, C1oH,2N2, and nicotelline, C10H$N2, in See also:tobacco. The name is taken from Nicotiana, the tobacco plant, so called after See also:Jean Nicot (1530-1600), See also:French See also:ambassador at See also:Lisbon, who introduced tobacco into See also:France in 156o. These four alkaloids exist in See also:combination in tobacco chiefly as malates and citrates. The alkaloid is obtained from an aqueous See also:extract of tobacco by See also:distillation with slaked See also:lime, the distillate being acidified with oxalic See also:acid, concentrated to a See also:syrup and decomposed by potash. The See also:free See also:base is extracted by See also:ether and fractionated in a current of See also:hydrogen. It is a colourless oil, which boils at 247° C. (745 mm.), and when pure is almost odourless. It has a See also:sharp burning See also:taste, and is very poisonous. It is very hygroscopic, dissolves readily in See also:water, and rapidly undergoes oxidation on exposure to See also:air. The free alkaloid is strongly laevo-rotatory. F. Ratz (Monats., 1905, 26, p. 1241) obtained the value [a]u=-169.54° at 20 its salts are dextro-rotatory. It behaves as a di-acid as well as a di-See also:tertiary base. On oxidation with chromic or nitric acids, or See also:potassium permanganate, it yields nicotinic acid or /3-See also:pyridine carboxylic acid, C5H,N'See also:CO2H; alkaline potassium ferricyanide gives nicotyrine, C,oH,0N2, and hydrogen peroxide oxynicotine, C,oH,4N20. Oxidation of its isomethylhydroxide with potassium permanganate yields trigonelline, C7H7NO2 (A. Pictet and P. Genequand, Ber., 1897, 30, p. 2117). It gives rise to various decomposition products such as pyridine, picoline, &c., when its vapour is passed through a red-hot See also:tube. The hydrochloride on See also:heating with hydrochloric acid gives methyl chloride (B. Blau, Ber.. 1893, 26, p. 631). Hydriodic acid and See also:phosphorus at high temperature give a dihydro-See also:compound, whilst See also:sodium and See also:alcohol give hexa- and octo-hydro derivatives. Nicotine may be recognized by the addition of a drop of 3o % formaldehyde, the mixture being allowed to stand for one See also:hour and the solid See also:residue then moistened by a drop of concentrated sulphruic acid, when an intense See also:rose-red See also:colour is produced (I. Schindelmeiser, Pharm. Zentralhalle, 1899, 40, p. 704). The constitution of nicotine was established by A. Pinner (see papers in the Berichte, 1891 to 1895). With See also:bromine in acetic acid See also:solution at See also:ordinary temperature, nicotine yields a perbromide, C,oH1oBr2N20•HBr3, which with See also:sulphur dioxide, followed by potash, gives dibromcotinine, CioH1oBr2N2O, from which cotinine, C,oH,2N20, is obtained by distillation over See also:zinc dust. By heating nicotine with bromine in hydrobromic acid solution for some See also:hours at too° C., dibromticonine hydrobromide, C,oHEN2Br2O2•HBr, results. Dibromcotinine on See also:hydrolysis yields oxalic acid, methylamine and $-methyl pyridyl ketone: C1oH10Br2N20+3H20+0= H2C204+CH3NH2+C5H4N•000H3+2HBr; whilst dibromticonine yields methylamine, malonic acid and nicotinic acid : C1oH1Br2N2O2+ 4H2O=CH3NH2+See also:CH2(CO2H)2+CSH4N•CO2H+2HBr, or if heated with zinc and See also:caustic potash, methylamine and pyridyl-,By-dioxybutyric acid. Thus the groupings U-C•C- —C•C— >N•See also:CH3 and —C•C•CN exist in the See also:molecule, and the alkaloid is to be represented as a-pyridyl-N-met hyl-pyrollidi ne. This result has been confirmed by its See also:synthesis by A. Pictet and P. Cr6pieux (Comptes rendus, 1903, 137, p. 86o) and Pictet and Rotschy (See also:Bee., 1904, 37, p. 1225): $-aminopyridine is converted into its mucate, which by dry distillation gives N-/3-pyridylpyrrol. By passing the vapour of this compound through a red-hot tube, it yields the isomeric ai3-pyridylpyrrol; the potassium See also:salt of which with methyl iodide gives a substance methylated both in the pyridine and See also:pyrrol nuclei. By distillation over lime, the methyl See also:group is removed from the pyridine See also:ring, and the resulting a-pyridyl-N-methylpyrrol gives i-nicotine on reduction. This base is resolved into its active components by d-tartaric acid, l-nicotine-d-tartrate crystallizing out first. The natural (laevo) base is twice as toxic as the dextro. The following formulae are important: N —CH 1 C =CH CH•CH2 0—C CH ~/ NH CH l\p N CH2 N / N \// N • \/ CH CH H,C CH2 N-0-Pyridylpyrrol, a$-pyridylpyrrol, nicotine. Acetyl and benzoyl derivatives of nicotine on hydrolysis do not yield nicotine, but an isomeric, inactive oily liquid (metanicotine). It is a secondary base, and boils at 275°-278° C. Nicotimine is a colourless liquid which boils at 25o°-255° C. Its aqueous solution is alkaline. Nicoteine is a liquid which boils at 267° C. It is separated from the other alkaloids of the group by distilling off the nicotine and nicotimine in See also:steam and then fractionating the residue. It is soluble in water and is very poisonous. Nicotelline crystallizes in needles which melt at 147° C. and is readily soluble in hot water. Additional information and CommentsThere are no comments yet for this article.
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