Trithiazyl chloride 1 converts the oximes of simple cyclic ketones into fused 1,2,5-thiadiazoles and bis-1,2,5-thiadiazoles in mild one-pot reactions. Cyclopentanone oxime gives the bisthiadiazole 3 (20%) in which all four methylene groups have been functionalised. Indan-1-one oxime 4 gives the thiadiazole 5 (63%), and tetralone oximes 6 and 8 give the bisthiadiazole 7 in low yields (20%) in complex reactions. Benzosuberone oxime 11 however gives only the monothiadiazole 12 (30%) which is not converted further with more trimer 1. These
reactions probably occur by mechanisms analogous to those proposed earlier for the conversion of alkenes, alkynes, active methylene compounds and enamines into 1,2,5-thiadiazoles. Bisthiadiazole 3, a reactive analogue of fluorene, condenses with p-anisaldehyde to give 13 and is oxidised by PCC to the fluorenone analogue 15 in low yield; 15 is formed directly from cyclopentane-1,3-dione with trimer 1. Ketone 15 condenses with malononitrile and Hünig's base to give the dicyanomethylene derivative 17 (94%) which forms a black metallic 1 ∶ 1 complex with TTF at room temperature.
Trithiazyl chloride 1 通过温和的单锅反应,将简单环酮的
肟转化为融合的
1,2,5-噻二唑和双-
1,2,5-噻二唑。
环戊酮肟可以得到双
噻二唑 3(20%),其中的四个亚甲基均已官能化。
茚酮
肟 4 可以生成
噻二唑 5(63%),四氢
萘酮
肟 6 和 8 在复杂的反应中可以生成双
噻二唑 7,但产率较低(20%)。然而,苯并环酮
肟 11 只生成了单
噻二唑 12(30%),而这种单
噻二唑 12 在三聚体 1 的作用下无法进一步转化。这些反应的发生机理可能与之前提出的烯、炔、活性亚甲基化合物和烯胺转化为
1,2,5-噻二唑的机理类似。双
噻二唑 3 是
芴的活性类似物,它与对
甲氧基苯甲醛缩合生成 13,并被
PCC 氧化为
芴酮类似物 15,产率较低;15 是由
环戊烷-1,3-二酮与三聚体 1 直接生成的。酮 15 与
丙二腈和 Hünig 碱缩合,得到二
氰亚甲基衍
生物 17(94%),该衍
生物在室温下与
TTF 形成黑色
金属 1 ∶ 1 复合物。