Abstract
The preparation of 2-(2,2,2-trichloroethylidene)cyclohexanone(1), as a key compound for synthesizing 2-substituted 5,6,7,8-tetrahydro-3-cinnolinones, was attempted by the enamine condensation of cyclohexanone with chloral. However, the condensation of 1-morpholino-1-cyclohexene (2) with chloral afforded 2-(1-hydroxy-2,2,2-trichloroethyl) cyclohexanone (3), and its dehydration led to 2-(2,2-dichlorovinyl)-2-cyclohexenone (4). 2-Aryl-5,6,7,8-tetrahydro-3-cinnolinones could be synthesized using morpholinium ${\alpha}$-(4-morpholinyl)-${\alpha}$-(2-oxocyclohexyl)-acetate (5) in place of 1 with arylhydrazines.
2-치환 5,6,7,8-테트라히드로-3-신놀린온 합성에 이용할 2-(2,2,2-트리클로로에틸리덴) 시클로헥산온(1)을 시클로헥산온과 클로랄의 엔아민축합으로 얻고자 하였다. 그러나 1-모르폴리노-1-시클로헥센(2)과 클로랄을 축합한 결과 2-(1-히드록시-2,2,2-트리클로로에틸)시클로헥산온(3)이 생성되었으며, 이것을 탈수시킨 결과 2-(2,2-디클로로비닐)-2-시클로헥센온(4)이 얻어졌다. 화합물 1대신에 ${\alpha}$-(4-모로폴린일)-${\alpha}$-(2-옥소시클로헥실)아세트산 모르폴린일륨(5)을 사용하여 아릴 하드라진들과 반응시킴으로써 2-아릴-5,6,7,8-테트라히드로-3-신놀린올들을 합성할 수 있었다.