Veratric aldehyde

Protocatechualdehyde has been made by a variety of methods, but is usually prepared from catechol by the Reimer-Tiemann method 1 by demethylation of vanillin,2 or veratric aldehyde 3 or from piperonal by the action of phosphorus pentachloride followed by hydrolysis.4... 

The 1-phenyltetrahydroisoquinolines cryptostyline I (7) and cryptostyline II (8) have been synthesized by the condensation of 3,4-dimethoxyphenylethyl-amine with piperonal and veratric aldehyde respectively, followed by treatment with ethyl chloroformate and reduction with lithium aluminium hydride.21... 

Homoveratric acid has been prepared by the methylation of homoprotocatechuic acid1 and of homovanillic acid2 with methyl iodide, and from veratric aldehyde through the azlactone and 3,4-dimethoxyphenylpyruvic acid.3 The procedure given here is adapted from that last mentioned and from that used for the preparation of -methoxyphenylacetic acid.4... 

In a i-l. round-bottomed flask, 83 g. (0.5 mole) of veratric aldehyde (Org. Syn. 13, 102) is dissolved in 200 cc. of warm 95 per cent alcohol, and a waim solution of 42 g. (0.6 mole) of hydroxylamine hydrochloride (Org. Syn. Coll. Vol. 1, 311) in 50 cc. of water is added. The two solutions are mixed thoroughly and a solution of 30 g. (0.75 mole) of sodium hydroxide in 40 cc. of water is introduced. After the mixture has stood for two and one-half hours at room temperature, 250 g. of crushed ice is added and the solution is saturated with carbon dioxide. This causes the separation of the aldoxime as an oil which solidifies on standing overnight in an ice chest (Note 1). The crystalline oxime is filtered with suction, washed thoroughly with water, and allowed to dry in the air. The yield of oxime is 88-89 g- (97 -9S per cent of the theoretical amount). 

Papaverine has been synthesized from the oxazole (19), obtained from the 2-lithio-derivative of 5-(3,4-dimethoxyphenyl)oxazole with veratric aldehyde, by catalytic reduction to the acyl-/ -phenylethylamine followed by Bischler-... 

Veratric Aldehyde (13,102) By methylation of vanillin with methyl p-toluene-sulfonate. Kanbvska, Arch. Phaim. 271, 462 (1933). 

The reaction mixture is transferred at once to a large beaker, covered with a watch glass, and allowed to cool without disturbance (preferably overnight). The hard, crystalline mass of veratric aldehyde is removed, ground in a mortar with 300 cc. of ice water, filtered with suction, and dried in a vacuum desiccator. The yield is 152-158 g. (92-95 per cent of the theoretical amount) of a product melting at 42.5-43.5 . 

Crude veratric aldehyde, obtained as described in the preceding paragraph, gives a 90 per cent yield of the oxime (m.p. 89-90 ) and an overall yield of 68-70 per cent of veratronitrile (m.p. 65-66 ). The nitrile thus produced is satisfactory for conversion to veratric amide and 4-aminoveratrole (p. 4) without further purification. 

Thebaol [lxvh, It = II] can be converted to /3-dimethylamino-ethylthebaol [lxvh, It = CH2 CII2 NMe2], which is degraded to acetylthebaol [lv] by hot acetic anhydride [43], Methylation of thebaol affords 3 4 6-trimethoxyphenanthrene [lxvh, It = Me] [79], identical with an authentic specimen prepared in the usual way from 2-nitro-veratric aldehyde and 4-methoxyphenylacetic acid [76]. 

If the reaction mixture is cooled too slowly or belov t 25°, the veratric aldehyde may solidify at this stage. If this occurs it is advisable to remelt the product before extracting with ether. 

Veratric aldehyde has been prepared from vanillin by methyl-ation with dimethyl sulfate or with methyl iodide, and from veratrole by reaction with hydrogen cyanide in the presence of aluminum chloride. ... 

The veratric aldehyde obtained by methylating vanillin (p. 102) may be used without further purification. 

The treatment of 3,4-dehydro-9-hydroxylaudanosine (18) with 2% acetic acid on the steam bath yields veratric aldehyde and hydroxylaudanosine, whereas the treatment of narco tine diol (19 R = OMe) and hydrastine diol (19 R = H) with acetic acid and tin(ii) chloride yields the reduced anhydro-compounds (20 R = OMe and H). The oxidation of narcotine with mercury(n) acetate and EDTA affords tarconine methyl ether (21), meconine, and opianic acid. ... 

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