benzoylcyanamide) affords the corresponding 2-diaminomethylidenecyclohexane-1,3-diones. The latter act as N,N-dinucleophiles in reactions with diethyl malonate in the presence of MeONa to form 6-hydroxy-2-(2,6-dioxocyclohexylidene)-1,2-dihydropyrimidin-4(3H)-ones. This reaction performed at 200 °C in the absence of bases results in the subsequent self-condensation of the dihydropyrimidinones to give 4
2-[(
氨基)(苯甲酰
氨基)亚甲基]
环己烷-1,3-二酮(
环己烷-1,3-二酮与苯甲酰
氰胺的加成产物)的脱苯甲酰化得到相应的2-二
氨基
亚甲基环己烷-1,3-二酮。后者在 MeONa 存在下与
丙二酸二乙酯反应形成 6-羟基-2-(2,6-二氧代环己基)-1,2-二氢
嘧啶-4(3H)-酮时充当 N,N-双亲核试剂。该反应在 200 °C 下在没有碱的情况下进行,导致随后的二氢
嘧啶酮自缩合生成 4,5'-联
嘧啶衍
生物。