Open Access Open Access  Restricted Access Subscription Access

1,3-DIPOLAR CYCLOADDITION OF DIPHENYLNITRILIMINE AND 5-ARYLMETHYLIDENE-1-PHENYL-1,5,6,7-TETRAHYDRO-4H-INDAZOL-4-ONES TO AFFORD NOVEL SPIRO[INDAZOLE-5,3'-PYRAZOLE] DERIVATIVES

Ren Demin, Kuang Guojiang, Li Xiaofang
Cover Image

Abstract


Novel 4'-aryl-1,2',5'-triphenyl-2',4',6,7-tetrahydrospiro[indazole-5,3'-pyrazol]-4(1H)-ones have been synthesized in moderate yields by 1,3-dipolar cycloaddition of 5-arylmethylidene-1-phenyl-1,5,6,7-tetrahydro-4H-indazol-4-ones and diphenylnitrilimine, generated in situ from N-phenylbenzohydrazonoyl chloride and triethylamine. According to structural analyses by NMR spectroscopy and single crystal X-ray diffraction method, the reaction proceeds regioselectively affording products with C(5)–C(3') connectivity at the spiro center.


Keywords


indazole, nitrilimine, pyrazole, spiro heterocycle, 1,3-dipolar cycloaddition.

Full Text: PDF Supplementary File(s): None


 

 

Latvian Institute of Organic Synthesis - Aizkraukles iela, 21, Riga, LV-1006, Latvia - hgs@osi.lv