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Chukhajian E O, Speaker at Catalysis Conference
The Scientific Technological Centre of Organic and Pharmaceutical Chemistry of National Academy of Sciences, , Armenia
Title : Base catalized intramolecular Cyclization of (4 hydroxybuth-2-ynyl)(3-(4-aryl)prop-2-ynyl)ammonium chlorides and intramolecular Recyclization of obtained products

Abstract:

It was established that for Cyclization of -(4-hydroxybuth-2-ynyl)[3-(4-aryl)prop-2-ynyl]ammonium chlorides (1) in the presence of  0,2 mol of alkali per mol of initial salt, unlike of propargylyc analogs, it is necessary the heating of reaction mixture at 45-50oC  during 10-15 min, then take place Cyclization with self-heating giving cyclic products 2 with high yields.
In these conditions with 13-15%  yields were obtained also amines 3, which are result of intramolecular Recyclization of cyclic products 2.
It was shown that the Cyclization of dialkyl(4-hydroxybuth-2-ynyl)[3-(4-bromphenyl)prop-2-ynyl]ammonium chlorides in water medium at step addition of twofold mol of water base on one mol of initial salts is realized with self-heating and following Recyclization of cyclic products 2, leading with high yields to formation of amines of Recyclization 3.
The chlorides of 2,2-pentamethylene-6-brombenzo[f]isoindolinium and (spiro-6-brombenzo[f]isoindolin)-2,4’-morpholinium in water solution at room temperature in the presence of  equimolar quantity of KOH smoothly undergo intramolecular Recyclization with formation of amines 3 with high yields.
The observing phenomenon is unique case in the field of intramolecular Recyclization. This can be explained by the fact that in the presence of bromine atom in the cycle is increased the electronic density of the molecule, thereby facilitates the ability of nucleophilic attack of alkoxy anion on a partially positive charged isoindolinium cycle.

Biography:

Prof.  Emma Chukhajian is Leading Scientist and Head of the laboratory of aminocompounds of The Scientific Technological Centre of Organic and Pharmaceutical Chemistry of National Academy of Sciences of Republic of Armenia. She obtained her Ph.D. in Science in 1970 and postdoctorial in the group of Academician Araksya T. Babayan. In 1969 with A. Babayan she discovered base-catalized intramolecular Cyclization of unsaturated ammonium salts containing β,ϒ-unsaturated groups along with 3-alkenyl(aryl)propargylic groups. In 2003 she with coauthors revealed intramolecular Recyclization of 4-hydroxymethylisoindolinium salts and their condensed derivatives. Among of cyclic products there are representatives with pharmacological activity. In 2008 – the phenomenon of isomerisation of 3a,4-dihydroisoindolinium salts, in 2011 – that Stevens rearrangement of the salts, containing allylic type group along with 4-hydroxybuth-2-ynyl, includes the stages of simultaneously transfer of reaction centre in accepting group and conversion of migrating group, in 2016 – phenomenon of deamination during vacuum distillation of 3-(dialkylamino)-1,4-diarylhex-5-en-1-yns and was worked out the method of preparation of terphenyle and its derivatives.

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