Six ß-dialkylamino ketones, one a-dialkylamino ketone and one -dialkylamino alcohol, were made, based on the 2,5-diphenyl-3-furyl system.The synthetic work involved a study of (a) the Friedel-Crafts acylation of 2,5-diarylfurans and bromination of the 3-acetyl group, and (b) conversion of the 3-carboxylic acid through the acid (VI). ( 6) Because of the objection to the handling of phenol, this and similar condensations were later carried out in dilute mineral acid according to a procedure used by Banks, This Journal, 66, 1127Journal, 66, (1944.
Experimental42-Methylamino-4,5-dimethylthiazole.-A mixture of methylamine hydrochloride (27 g., 0.4 mole), water (100 ml.) and I (51.6 g., 0.4 mole) was heated at reflux temperature (103°) for 8 hr. The immiscible layer of I disappeared. After cooling the mixture to room temperature the solution was extracted three times with 50-ml. portions of ether to remove unreacted I. After treating with decolorizing carbon the solution was concentrated to one-fourth its volume. White crystals of the hydrochloride were obtained (8.4 g.-11.8%) which melted at 284-287°after recrystallization from ethanol. Anal. Caled, for CsHnClN^S: Cl, 19.84; S, 17.94. Found: Cl, 20.00; S, 18.10. The rest of the product was isolated by neutralization to give the free base (37 g.-65.1%). The white crystalline solid melted at 125-128°after recrystallization from benzene and ethanol. Anal. (See Table I).2-Anilino-4,5-dimethylthiazole. (a) From I and Aniline.-A solution of aniline (93 g., 1 mole), aniline hydrochloride (2.8 g.) and I (64.5 g., 0.5 mole) in benzene (200 ml.) was placed in a flask which was equipped with a 1 X 12-inch column, packed with berl saddles, and an esterification head. The esterification head was designed to separate the water removed by azeotropic distillation with benzene and to continuously return the benzene to the reaction flask. The solution was heated until 8.5 ml. (94.4% of theory) of water was isolated. The benzene and excess aniline (96% recovery) were removed by distillation at 30-50 mm.
It is a matter of some interest to compare the pharmacological properties of substances which contain a phenyl radical with corresponding athienyl compounds.3In this paper we have described a series of athienylaminoalkanes which were examined pharmacologically by L. W. Rowe in the Parke, Davis and Company laboratories. As far as ability to 13, 305 (1940). The analogous l-(«-phenyl-'-furyl) and l-ta-phenyl-a'-pyrryl) compounds also exhibited some activity. Robinson and Todd [/. Chem. Soc., 1743 (1939] prepared 2-(a/-phenyl-a-thienyl)-and 2-(a/-£-methoxyphenyl-a-thienyl) -ethylamine as well as a few of the corresponding furyl and pyrryl compounds.(8) For a discussion of this reaction see Heidelberger, "An Ad-
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