CHLOROSULFONATION OF 9-ARYLOCTAHYDROXANTHEN-1,8-DIONES

The 9-aryloctahydroxanthen-1,8-diones (3, 4– 24) were prepared by reaction of cyclohexan-1,3-dione (1) with selected arylaldehydes. The xanthendiones (4– 9, 11, 12, 18, 21, 22) were successfully reacted with chlorosulfonic acid, and the crude sulfonyl chlorides were converted into 15 sulfonamides (26– 40) for screening as potential pesticides. Attempted chlorosulfonation of the xanthendiones (13– 17) was unsuccessful. α-Methylcinnamaldehyde was reacted with cyclohexandione (1) to yield the corresponding xanthendione derivative (23). On the other hand, with o-methoxycinnamaldehyde an impure product formed and the p-methoxy isomer afforded the corresponding 2-arylpyran (25). The NMR spectral data of the compounds are briefly discussed.