Russian Chemical Bulletin, International Edition, Vol. 53, No. 8, pp. 1717—1721, August, 2004 1717 1066-5285/04/5308-1717 © 2004 Springer Science+Business Media, Inc. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1652—1656, August, 2004. Multicomponent heterocyclization of hydrazine, hydrogen sulfide, and formaldehyde S. R. Khafizova, V. R. Akhmetova,  T. V. Tyumkina, L. M. Khalilov, R. V. Kunakova, and U. M. Dzhemilev Institute of Petrochemistry and Catalysis, Bashkortostan Republic Academy of Sciences and Ufa Research Center of the Russian Academy of Sciences, 141 prosp. Oktyabrya, 450075 Ufa, Russian Federation. Fax: +7 (347 2) 31 2750. E-mail: ink@anrb.ru Multicomponent heterocyclization of hydrazine, hydrogen sulfide, and formaldehyde gave previously unknown bi-, tri-, and tetracyclic nitrogen- and sulfur-containing heterocycles. 3,7-Dithia-1,5-diazabicyclo[3.3.0]octane, 4,9-dithia-1,2,6,7-tetraazatricyclo[5.3.1.1 2,6 ]do- decane, and 4,9,14-trithia-1,2,6,7,11,12-hexaazatetracyclo[10.3.1.1 2,6 .1 7,11 ]octadecane were obtained selectively, depending on the reaction temperature (0—60 °C). Key words: heterocyclization, thiomethylation, hydrazine, formaldehyde, hydrogen sul- fide, 3,7-dithia-1,5-diazabicyclo[3.3.0]octane, 4,9-dithia-1,2,6,7-tetraazatricyclo[5.3.1.1 2,6 ]do- decane, 4,9,14-trithia-1,2,6,7,11,12-hexaazatetracyclo[10.3.1.1 2,6 .1 7,11 ]octadecane. One-pot methods for the synthesis of heterocycles with practically useful properties are of particular interest and hold promise. 1 According to available data, 2—8 multicom- ponent thiomethylation of primary amines with hydrogen sulfide and formaldehyde yields dithiazines and linear bis(N-alkylmethyl) sulfides, while similar reactions with ammonia and hydrazine afford polycyclic systems con- taining thiadiazine and thiadiazolidine fragments. Thiaza- heterocycles exhibit biocidal activity and find use as extractants, complexones, and flotation agents for metals. 9,10 With the aim of extending the area of application of this method and of synthesizing novel types of nitrogen- and sulfur-containing heterocycles, we studied the reac- tion of hydrazine with hydrogen sulfide and formalde- hyde under different reaction conditions. Results and Discussion About half a century ago, 8 the product with the mo- lecular formula C 4 H 8 N 2 S 2 was obtained in 11% yield by the reaction of hydrazine with formaldehyde and hydro- gen sulfide in the 1 : 2 : 2 ratio at T < 0 °C. Later, 11 the 1,3,4-thiadiazolo[3,4-c]-1,3,4-thiadiazole structure was assigned to that product, though no confirming spectro- scopic data were reported. We studied the effects of the temperature and the ratio of the reagents on the thio- methylation of hydrazine with a CH 2 O—H 2 S system pre- pared by bubbling gaseous hydrogen sulfide through a formalin solution. It was found that the heterocyclization of hydrazine 1 with an excess of the CH 2 O—H 2 S mixture (1 : 6 : 4) in the temperature range from 0 to 60 °C gives bi-, tri-, and tetracyclic nitrogen- and sulfur-containing heterocycles 2—4, depending on the reaction tempera- ture (Scheme 1). Scheme 1 It turned out that the direction and selectivity of the thiomethylation of hydrazine is substantially affected by the temperature. For instance, at 40 and 60 °C, the reac-