GB858839A - Novel substituted azulenes - Google Patents

Abstract

The invention comprises substituted azulenes of the general formula : <FORM:0858839/IV(b)/1> wherein X represents a cyano group or the radical produced by removing an active hydrogen atom from an organic compound having at least one such active hydrogen, which azulenes may also be substituted elsewhere in the azulene nucleus, and of the formula : <FORM:0858839/IV(b)/2> wherein X represents the radical of an organic compound having two or more active hydrogen atoms, which radical has two less hydrogen atoms than said organic compound both of which hydrogen atoms have been removed from the same carbon atom which azulenes may also be substituted elsewhere in the azulene nucleus, and processes from the preparation of substituted azulenes wherein (a) an azulene substituted in the 1- and (or 3 position by an aminomethyl or hydroxymethyl group is reacted with an organic compound having at least one reactive hydrogen atom ; (b) a quaternary salt of an p azulene substituted in the 1- and/or 3-position by an amino-methyl group is reacted with a metal salt of an organic compound having at least one reactive hydrogen atom and (c) a 1- and/or 3-immonium salt of an azulene is reacted with a metal salt of an organic compound having at least one reactive hydrogen atom. Specified compounds with active hydrogen atoms are ethyl malonate, ethyl cyanoacetate, nitro-methane barbituric acids, anti-pyrine, phenyl methyl pyrazolone, piperidine and phenol. Solvents mentioned include benzene and petroleum ether. Substituents which may be present in the azulene nucleus include alkyl, aryl, halogen, nitro, azo, or acyl groups and an additional -CH=X group. Examples are furnished relating to the preparation of 1-piperidinomethyl guaiazulene from 1- hydroxymethyl-guaiazulene and piperidine in the presence of perchloric acid and acetone, 4, 6, 8-trimethyl azulyl methyl diethyl malonate from sodium diethyl malonate and dimethylaminomethyl-4, 6, 8-trimethyl azulene in the presence of tetrahydrofuran, 4, 6, 8-trimethyl azulyl acetonitrile from potassium cyanide and 1-dimethylaminomethyl-4, 6, 8-trimethyl azulene methiodide in aqueous solution, 1-(4, 6, 8-trimethyl azulyl)- ethylene-2-dicarboxylic acid diethyl ester from 4, 6, 8-trimethyl azulyl-1-methyl-dimethyl immonium chloride and sodium ethyl malonate, the product optionally being saponified to the corresponding dicarboxylic acid and 1-methyl-3-cyanomethyl azulene from 1-methyl azulyl-3-methyl-trimethyl ammonium iodide, acetonitrile, ethanol, water and potassium cyanide. Aminomethyl azulenes for use as starting materials are obtained by reacting azulenes unsubstituted in the 1-position and/or the 3-position with formaldehyde and amines under the conditions of the Mannich reaction. 1-dimethylaminomethyl-4, 6, 8-trimethyl azulene is prepared from 4, 6, 8-trimethylazulene, bisdimethyl amino-methane and paraformaldehyde. 1- and/or 3- hydroxymethyl azulenes are obtained by reduction of azulene aldehydes and ketones with lithium aluminium hydride or aluminium dialkyl hydride. 1-Hydroxy-ethylguaiazulene is obtained by reacting guaiazulene aldehyde-1 with methyl magnesium bromide. 4, 6, 8-Trimethyl azulyl-1-methyl-dimethyl immonium chloride is prepared by reacting 4, 6, 8-trimethyl azulene and phosphorus oxychloride in dimethyl formamide. Specification 750,209 is referred to.