Abstract
The 1,2-thiazoles obtained from 3-chloroalk-2-enals and ammonium thiocyanate (7 to 9, Scheme 1) are easily transformed to 1,2-thiazol-3(2H)-one 1,1-dioxides 10 on treatment with H202 in AcOH at 80°. Hydrogenation of 10 in AcOH yields the corresponding saturated 1,2-thiazolidin-3-one 1,1-dioxides 16 (Scheme 3). Cycloalka[c]-1,2-thiazoles 18 are prepared from 2-[(thiocyanato)methyliden]cycloalkan-l-ones and ammonia (Scheme 4). Surprisingly, oxidation of 18a with H202 in AcOH yields the tricyclic oxaziridine 19.
Schulze, Bärbel