The Synthesis Of Novel Spiroheterocycles By The1,3-dipolar Cycloaddition Reaction Of Azomethine Ylides

The paper focus on the study of the synthesis of a number of novelspir-oheterocycles by the1,3-dipolar cycloaddition reaction of AzomethineYlides. The1,3-dipolar cycloaddition reaction of azomethine ylides withexocyclic olefins repr-esents an efficient method for the construction of thespirooxindole structural unit.49novel dispiroheterocycle compounds weresynthesized by the1,3-dipolar cycloadditi-on of azomethine ylide whichgenerated in situ from sarcosine and isatin or sarcosine and acena-phthen-equinone and self-synthesized dipolarphiles with exo-cyclic double bond.There are six series of new heterocycle among them. Which can bedescribed into two portions as followed:1.The1,3-dipolar cycloaddition of an azomethine ylide generated by adecarboxylative route from sarcosine and isatin to:7-arylmethylidene-3-aryl-3,4-dihydro-2H-thiazolo[3,2-a][1,3,5]triazin-6(7H)-ones, the mixtureof4-aryl-octahydro-pyrano[2,3-d]pyrimidine-2-thione, dim-ethyl and acet-ylenedicarboxylate(DMAD),2-arylmethylidene-2,3-dihydro-1H-pyrrolizin-1-ones],afforded: noveldispiro[oxindole-pyrrolidine]-thiazolo[3,2-a][1,3-,5]triazines,1’-methyl-2,3’’-di-oxo-5’’-aryl-1,2,5a’’,7’’,8’’,9a’’-hexah dro-5’’H,6’’H-dispiro[indole-3,2’-pyrrolidine-3’,2’’-pyrano[2,3-d][1,3]thiazolo[3,2-a]pyrimidine]-4’-carboxylic acid methylester],and[1’-methyl-4’-(aryl)-1’’H-di-spiro[indole-3,2’-pyrrolidine-3’,2’’-pyrrolizine]-1’’,2(1H)-diones inmoderate yields.2.7-arylmethylidene-3-aryl-3,4-dihydro-2H-thiazolo[3,2-a][1,3,5]triazin-6(7H)-ones,2-arylm-ethylidene-5-phenyl-5a,7,8,9a-tetrahydro-5H,6H-pyrano[2,3-d][1,3]thiazolo[3,2-a]pyrimidin-3(2H)ones,(obtained by reaction of4-phenyl-octahydro-pyrano[2,3-d]pyrimidine-2thi-one,ethyl ch-loroacetate and the appropriate aromatic aldehyde),7-arylmethy-lidene-6,7-dihydroindolizin-8(5H)-ones, afforded: dispiro[acenaphthylene-1,2’-pyrrolidine]-3’,7’’-[1,3]thiazolo[3,2-a][1,3,5]triaz-ines,[4’-aryl-1’-methyl-5’’-phenyl-5a’’,7’’,8’’,9a’’-tetrahydro-2H,5’’H,6’’H-dispiro[acenaphthylene-1,2’-pyrrolidine-3’,2’’-pyrano[2,3-d][1,3]thiazolo[3,2-a]pyrimidine]-2,3’’-diones,and4’-aryl-1’-methyl-5’’,6’’-dihydro-2H,8’’H-dispiro[acenaphthylene-1,2’-pyrrolidine-3’,7’’-indolizine]-2,8’’-diones in moderate yields.The structures of the products were determined and characterized thoroughly by NMR, MS, IR, elemental analysis and X-ray crystallographicanalysis. The results of experiment indicated that this1,3-dipolarcycloaddition proceeded with high stereoselectivity and regioselectivity.