Abstract
1,3-Dipolarcycloaddition reactions of 6-arylmethylene-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-ones (1) with nitrilimines 3 were investigated in benzene and chloroform. The reaction products were 2',4',6,7,8,9-hexahydro-2',4',5'-triaryl spiro[benzocycloheptene-6(5H),3'(3H-pyrazol)-5-ones (4) or spiro[benzocycloheptene-6(5H),4'(4H-pyrazol)-5-ones (5). X-ray crystallographic analysis was carried out for compound 5b. It was found that the regioselectivity of the produced compounds was altered based on changing solvent type. (C) 2012 Elsevier Ltd. All rights reserved.