HETARYLSULFONIUM SALTS BY CYCLIZATION

Reaction of tetrahydrothiophene with the N-(iodoacetyl)anthranilic aci d derivatives 1a, b and 2-(iodoacetylamino)acetophenone (1c) yields th e 1-(2-oxoquinolin-3-yl)tetrahydrothiophenium salts 3a-c in two steps. Analogously the heterocondensed 1-(2-oxopyridin-3-yl)tetrahydrothioph enium salts 6 and 7 can be prepared. The 1-(3-oxopyridazin-4-yl)- and (2-oxopyridin-3-yl)tetrahydrothiophenium salts 10, 13, 16, 18 are synt hesized on the same way. From the tetrahydrothiophenium salt 3a the 3- (alkylthio)-4-aminoquinolin-2(1H)-ones 19 arise.