Studies on the syntheses of aliphatic diamines. Xii

Abstract

1, 7-Diaminoheptane has been synthesized from 1, 7-dichloroheptene-3 through ammonolysis followed by hydrogenation. For the formation of the desirable primary amine in the ammonolysis reaction, the following conditions have been proved favorable: use of liguid ammonia with or without a small amount of water or an organic solvent rather than aqueous ammonia, use of an excessive amount of ammonia, reaction temperatures above 80°C, in case of aqueous ammonia and above 60°C, in case of liquid ammonia, the effects of temperature upon yield being small over the range 100~140°C, and efficient agitation to ensure thorough contact of the reactants. The maximum yield of 1, 7-diaminoheptene-3, however, was 72~73%. Attempts to improve the yield resulted in the formation of secondary and tertiary polyamine by-products. 1, 7-Diaminoheptene-3 thus obtained was readily hydrogenated into 1, 7-diaminoheptane in 96% yield in the presence of Raney nickel catalyst under the atmospheric pressure as well as under pressure. Condensation polymerization of 1, 7-diaminoheptene-3 and that of 1, 7-diaminoheptane with urea proceeded smoothly and white solid polyureas with good spinning properties were obtained. The former polyurea showed m.p. 216°C, d204 1.13 and the latter, m.p. 260°C, d20 1.12. The melting point of the polyurea obtained from 1, 9-non amethylenediamine fell between that of the two polymers, and the specific gravity of the former was approximately 5% less than that of the latter two. The fiber of 1, 7-diaminoheptene-3 polyurea as well as that of 1, 7-diaminoheptane polyurea showed a slightly better dyeing properties with acidic and dispersing dyes than 1, 9-nonamethylenediamine polyurea, though other properties of those three types of fiber were alike. © 1965, The Society of Synthetic Organic Chemistry, Japan. All rights reserved.