Studies On The Synthesis Of Isothiazolones And 3-benzylidenetetrahydrofuran Compounds

In recent years,isothiazolinone and tetrahydrofuran derivatives have been widely used in the fields of medicine and chemical industry.Given the importance of isothiazolinone and tetrahydrofuran derivatives,the cost-effective synthesis of isothiazolinone and 3-benzylidenetetrahydrofuran derivatives still face significant challenges.The three-membered ring compounds have a special tension that make their C-C bond broken easily,and show high reactivity in organic synthesis.This paper mainly studies the methods for the construction of isothiazolinone and3-benzylidenetetrahydrofuran derivatives via the ring-opening reaction of three-membered ring compounds.The text contains the following two parts:Part I:Study on preparing isothiazolinone by the ring-opening reaction of cyclopropenoneDescribed herein is the synthesis of isothiazolone via Fe（Ⅲ）-catalyzed three-component reaction of cyclopropenone,aniline,and elemental sulfur.The cascade reaction involves the C-S,C-N,and N-S bond formation along with the ring-opening of cyclopropenone.The method is suitable for a wide range of substrates,polysubstituted anilines,symmetric and asymmetric diphenylcyclopropenones can smoothly react to obtain the target product in good yield.Simultaneously,the[3+1+1]cyclization strategy of cyclopropenones also has been extended to the synthesis of isoselenazolinones.Part II:Study on preparing 3-benzylidenetetrahydrofuran by the ring-opening reaction of cyclopropyl（aryl）methanolThe 3-benzylidenetetrahydrofuran compounds are synthesized by cyclization of DMSO with homoallylic alcohol which is generated by the isomerization and ring-opening of cyclopropyl（aryl）methanol under Tf₂O catalysis.In this reaction,the solvent DMSO is activated by Oxone^?to afford sulfenium ion intermediate,which provides carbon source for the construction of 3-benzylidenetetrahydrofuran compounds.The method shows good compatibility for cyclopropyl（aryl）methanol compounds with different types of substituents,and can obtain a series of3-benzylidenetetrahydrofuran derivatives in good yields.