Studies of derivatives of diacetylene

Diacetylene: a candidate for industrially important reactions

“…The reaction of diacetylene with primary amines in the presence of copper(I) salts occurs as 1,4-addition and results in the formation of pyrrole or 1-alkylpyrroles. 3 This reaction is carried out at 140 ± 160 8C both in the absence of the solvent and in methanol, ethanol or DMF. In the latter case, the resulting pyrroles have a high degree of purity and are formed in higher yields.…”

“…The reaction of ammonia and primary alkyl-and arylamines with disubstituted symmetrical 1,3-diynes in the presence of copper(I) chloride affords 1,2,5-trisubstituted pyrroles 23. 3 According to Shostakovsky and Bogdanova, 3 the role of a catalyst in this reaction consists in the formation of a non-polar p-complex with one of the triple bonds where the electron density is evenly distributed between both carbon atoms, which facilitates the interaction of the nucleophilic nitrogen with the fourth carbon atom of the conjugated diyne system. The smooth course of this reaction made it possible to develop a general scheme for the synthesis of substituted pyrroles.…”

“…Despite the fact that many compounds of the diacetylene series (1,3-diynes) had been known since the XIX century, the development of the chemistry of these compounds began only after 1950 3 when they were discovered in nature 4,5 as well as among the products of electrocracking and oxidative pyrolysis of methane. 6 Under industrial conditions, these two reactions yield, in addition to acetylene, some of its homologues and derivatives among which diacetylene constituting 5% of the whole manufacture of acetylene presents the greatest practical interest.…”

“…Higher alkynes and diacetylene are extracted with the help of selective solvents, e.g., anhydrous ammonia, cooled methanol, N-methylpyrrolidone, DMF. 3,6 The first solution to this problem was proposed and implemented at the oldest petrochemical plant `Chemische Werke Huls A.G.' 41 Preparation of 1-methoxybut-1-en-3-yne as a 50% solution in methanol from accompanying diacetylene has been described. 42 However, this method is not industrially acceptable because of extremely high diacetylene concentrations in the reactor.…”

“…The reaction of diacetylene with secondary amines gives 1-dialkylaminobut-1-en-3-ynes (3). 3,47 The stereochemistry of the reaction of diacetylene with diethylamine in various solvents and at different temperatures resulting in the formation of the Z-and E-isomers 3b has been studied. 50 The E : Z ratio increases with temperature.…”