ALKYNYLATION REACTIONS OF SOME HETEROATOMIC ALDEHYDES IN THE PARTICIPATION OF PHENYLACETYLENE

391 Volume 5, Issue 10: Special Issue (EJAR) ISSN: 2181-2020 MPHAPP THE 6TH INTERNATIONAL SCIENTIFIC AND PRACTICAL CONFERENCE “MODERN PHARMACEUTICS: ACTUAL PROBLEMS AND PROSPECTS” TASHKENT, OCTOBER 17, 2025 in-academy.uz ALKYNYLATION REACTIONS OF SOME HETEROATOMIC ALDEHYDES IN THE PARTICIPATION OF PHENYLACETYLENE Saliyeva M.K.1 Ziyadullayev O.E.2 1Tashkent Pharmaceutical Institute, Tashkent, Uzbekistan 2Academy of the Ministry of Emergency Situations of the Republic of Uzbekistan, Tashkent, Uzbekistan email: [email protected], tel: (93)5933309 https://doi.org/10.5281/zenodo.17339501 Relevance: In our country, the synthesis of new types of chemicals that have found their place in the world market, the creation of methods for obtaining import-substituting compounds intended for export, and their use in the pharmaceutical, chemical, energy, and construction sectors are urgent tasks, and scientific research is being conducted in this area and certain results are being achieved. The purpose of the research: To carry out the synthesis of acetylenic alcohols based on the alkynylation reaction of some aldehydes containing heteroatom substituents in their molecules with phenylacetylene in the presence of a new catalytic system InBr3/Et3N/Et2O, to systematically study the effect of the molar ratios of the starting materials, reaction duration, temperature, nature of the catalyst and solvents on the product yield, and to determine the efficiency range of the formation of acetylenic alcohols based on the effect of heteroatoms in the aldehyde molecule on the product yield, and to identify their composition, purity, and structure using physicochemical methods. Methods and techniques: A new generation of acetylenic alcohols was synthesized by alkynylation of aldehydes containing heteroatom substituents - thiophene-2-carbaldehyde, furan-2carbaldehyde, and pyridine-3-carbaldehydes with phenylacetylene in the presence of the InBr3/Et3N/Et2O catalytic system. The reaction scheme is proposed as follows. + R O H C CH R H OH C C 1-3 InBr3Et3N/Et2O 20 o C, 120 min S H OH O H OH H OH N 1 2 3 Results: The following acetylenic alcohols - 1-(thiophenyl-2)-3-phenylpropyn-2-ol-1 (1), 1- (furanyl-2)-3-phenylpropyn-2-ol-1 (2), 1-(pyridinyl-3)-3-phenylpropyn-2-ol-1 (3) - were synthesized by alkynylation of aldehydes containing heteroatom substituents in the molecule - thiophene-2carbaldehyde, furan-2-carbaldehyde, pyridine-3-carbaldehyde with phenylacetylene in the presence of the InBr3/Et3N/Et2O catalytic system. The effects of the molar ratios of the starting materials, reaction duration, temperature, nature of the catalyst and solvents on the product yield were systematically studied. Based on the effect of heteroatoms in aldehyde molecules on product yield, the efficiency range of acetylenic alcohols was determined, and their composition, purity, and structure were identified using physicochemical methods. 392 Volume 5, Issue 10: Special Issue (EJAR) ISSN: 2181-2020 MPHAPP THE 6TH INTERNATIONAL SCIENTIFIC AND PRACTICAL CONFERENCE “MODERN PHARMACEUTICS: ACTUAL PROBLEMS AND PROSPECTS” TASHKENT, OCTOBER 17, 2025 in-academy.uz Conclusions: Based on the results obtained, the most optimal conditions for the synthesis of acetylene alcohols in the InBr3/H2O/Et3N/Et2O catalytic system were found. According to them, the nucleophilic addition reactions of phenylacetylene with selected aldehydes were carried out in a diethyl ether solution in the presence of the catalyst InBr3 for 120 minutes at a temperature of 20 °C, with a 1:1 molar ratio of the starting materials, and the highest yield of acetylene alcohols was determined.