Reactions of 1,3-Thiazine-2,6-dithiones. Part 8. Formation of a New Series of 2-Pyrroline-4-thiones by the Rearrangement of 1,3-Thiazine-6-spiro-2’-thiirane-2-thiones and 2-Methylthio-1,3(6H)-thiazine-6-spiro-2’-thiiranes and Some Related Reactions
作者:Tatsuo Yamamoto、Hiroshi Miyamae、Motomu Muraoka
DOI:10.3987/com-17-13831
日期:——
1,3(6H)-Thiazine-6-spiro-2'-thiirane-2-thiones 2a-c and 3',3'-di substituted 2-methylthio-1,3-thiazine-6-spiro-2'-thiiranes 12a-f were synthesized by the reaction of 1,3-thiazine-2,6-dithiones 1 or 11a-d, which are 2-methylthio derivatives of thiazinedithiones 1, with diazomethane derivatives. 1,3(6H)-Thiazine-6-spiro-2'-thiiranes 2a-c and 12a-f rearranged into a series of 2-pyrroline-4-thione derivatives 3a-c and methyl 4-thioxopyrroline-1-dithiocarboxylates 13a-f on treatment with a base or gentle heating. 2-Pyrroline-4-thione derivative 13c, upon heating to 140 degrees C for 1 h, reversely rearranged into the thiirane derivative 12c. The structure of the 2-pyrroline-4-thione 13e was determined by single-crystal X-ray analysis.