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In the presence of 0.2 mol of aqueous KOH to 1 mol of the initial salt dialkyl(2-butynyl-4-hydroxy)-(3-R 1 -propargyl)ammonium salts (R 1 = Ph, vinyl, or isopropyl) undergo cyclization, forming 2,2-dialkyl-4-hydroxymethylisoindolinium and 2,2-dialkyl-4-hydroxymethylbenzo[f]isoindolinium salts [1][2][3].While studying the question of the stability of the above-mentioned salts under the conditions of aqueous alkaline cleavage we discovered intramolecular recyclization, which included a stage with cleavage of the isoquinoline ring by the action of the alkoxide ion formed in the alkaline medium and the formation of a dihydrofuran ring [2][3][4][5]. It was established that the recyclization process was facilitated by increase in the number of aromatic rings and by the presence of a methyl substituent in the benzene ring. Thus, heating of the reaction mass for only 40-60 min is required for the recyclization of benzo[5,6;5′,6′-a,c]di[2,2-dialkyl-4-hydroxymethyl]isoquinolinium [5].In order to investigate further the effect of the structure of the initial salts on their cyclization and the subsequent recyclization of the obtained products and also to obtain new potentially active isoindolinium R 2 N Cl O H R 2 N OH R 1 1a-c 2a-c 1a-c R 1 = C 6 H 4 Cl-p, 1, 2 a R = Pr, b R 2 = (CH 2 ) 5 , c R 2 = (CH 2 ) 2 O(CH 2 ) 2 + + 1 1' 3' 1 3 5 8 4 OH -Cl Cl --__________________________________________________________________________________________

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Keywords: 4-(dialkylaminomethyl)-1,3-dihydrophenanthro[1,2-c]furans, 4-(dicyclohexylaminomethyl)-1,3-dihydronaphtho[1,2-c]furan, 1-(1,3-dihydronaphtho[1,2-c]furan-4-ylmethyl)-4-(p-fluorophenyl)piperazine, dialkyl(4-hydroxy-2-butynyl)[3-(-naphthyl)-2-propynyl]ammonium chlorides, intramolecular cyclization and recyclization in the presence of base.It has previously been shown that R 2 -(4-hydroxy-2-butynyl)(3-R 1 -2-propynyl)ammonium chlorides (where R = Alk, R + R = (CH 2 ) n , (CH 2 ) 2 O(CH 2 ) 2 , R 1 = Ph, p-ClC 6 H 4 , alkenyl) undergo cyclization in the presence of aqueous KOH solution (5:1 molar ratio of salt to base) to form the corresponding 2,2-R-4-(hydroxymethyl)isoindolinium chlorides [1][2][3][4]. Initiation of the reaction requires preheating of the reaction mixture to 50-55ºC after which the temperature spontaneously rises to 85-90ºC and over 5-10 min the cyclization products are formed. It was also found that the formation of recyclization products (e.g. with R 1 = p-ClC 6 H 4 [3]) occurs

prop-2-ynyl}benzene dichlorides, dialkyl (6-dialkylaminomethyl-7,9,10,12-tetrahydro-8,11-dioxadicyclopenta[c,g]-phenanthren-1-ylmethyl)amines, base catalysis, double intramolecular cyclization, intramolecular recyclization. [3-dialkyl-2-propynylammonio-1-propynyl]benzene dibromides under base catalysis conditions undergo a double intramolecular cyclization of the diene synthesis type with the formation of benzo [5,6;5',6'-a,c]di(2,2-dialkylisoindolinium dibromides in almost quantitative yield [1]. NR 2 N NR 2 N + + Br -Br -R 2 OH -R 2 Br -Br -+ + __________________________________________________________________________________________ p-Bis