Treatment of 2,3-dihydro-4aH-cyclohepta-1,4-dithiin with triphenylmethyl tetrafluoroborate followed by condensation with α-bromomalononitrile in pyridine afforded 5- and 7-(dicyanomethylene)-2,3-dihydrocyclohepta-1,4-dithiins in good yields. When changing the solvent to acetonitrile, the products obtained were 5- and 6-(2,2-dicyanoethyl)-2,3-dihydro-1,4-benzodithiins. This new method was applicable
用四
氟硼酸三苯甲酯处理 2,3-二氢-4aH-环庚-1,4-二噻英,然后在
吡啶中与 α-
溴丙二腈缩合,得到 5-和 7-(二
氰基亚甲基)-2,3-二氢环庚-1,4-二噻英收益良好。将溶剂改为
乙腈,得到的产物为5-和6-(2,2-二
氰乙基)-2,3-二氢-1,4-苯并二噻英。这种新方法适用于从托鎓盐一般合成二
氰基七富烯。