The synthesis of a series of new 2-[(substituted phenyl)methyl]-4-[1,3-dithiolan-2-ylidene]-isoxazolidine-3,5-diones is described for the evaluation of the pesticidal activities.
The requisite 1,3-dithiolan-2-ylidene malonyl chloride was prepared by the hydrolysis of the commercially available diisopropyl-1,3-dithiolan-2-ylidene malonate(isoprothiolane), followed by chlorination. The desired product, 2-[(substituted phenyl)methyl]-4-[1,3-dithiolan-2-ylidene]-isoxazolidine-3,5-diones were synthesized by a reaction of appropriate aromatic hydroxylamine and 1,3-dithiolan2-ylidene malonly chloride in the presence of pyridine as catalyst.
The aromatic hydroxylamines were prepared by the reaction of aromatic aldehyde with hydroxylamine hydrochloride, followed by reduction with sodium cyanoborohydride.
The structure of synthesized products was determined by means of their I.R, $^1H$-NMR, Mass spectra and elemental analysis.
The electron-impact(E.I)mass spectra of these compounds at 70 eV showed some novel fragmentation pathway along with general decomposition. It was observed that the parent molecular ion undergoes primarily cleavage of amide C-N bond or N-O bond in the isoxazolidine-3,5-dione ring, followed by oxygen transfer to produce four-membered ring system.
신규농약 개발의 일환으로 새로운 N-벤질-4-[1,3-디티올란-2-일리덴]-이속사조리딘-3,5-디온을 합성하였다. 여기에 필요한 1,3-디티올란-2-일리덴 마로닐 클로라이드는 디이소프로필-1,3-디티올란-2-일리덴 말로내이트를 가수분해 하고, 염소화 함으로써 만드러졌다. 그리고 이것을 적당한 히드록실 아민과 반응시킴으로써 원하는 최종물질을 합성하였다. 이때 촉매로써 피리딘을 사용하였다.
합성된 화합물들은 자외선 분광 스펙트럼, 핵자기 공명 스펙트럼, 질량분석 스펙트럼, 그리고 원소분석에 의하여 그 구조가 확인되었다. 특히 전자 충돌 방법을 사용한 질량분석 스펙트럼이 연구되었으며, 합성된 화합물에 대해서 쪼개지는 과정을 설명하였다. 여기서 아이소옥사조리딘-3,5-아이원 링의 두가지 가능한 절단을 생각 할 수 있었다.
