S(=O)(=O)(O)O.O[CH:7]1[C:13]2[CH:14]=[CH:15][CH:16]=[CH:17][C:12]=2[CH2:11][CH2:10][CH:9]([NH2:18])[CH2:8]1.O1CCOCC1>O>[NH2:18][CH:9]1[CH:8]=[CH:7][C:13]2[CH:14]=[CH:15][CH:16]=[CH:17][C:12]=2[CH2:11][CH2:10]112 ml of 18N sulfuric acid were added to a refluxing mixture of 5.6 g of the product of Step C and 60 ml of dioxane and the mixture was refluxed for 2 hours and then was cooled to 20° C. The mixture was poured into 300 ml of water and the neutral fraction was extracted with ether. The aqueous phase was made alkaline with sodium hydroxide addition and was extracted with ethyl acetate. The ethyl acetate extracts were washed with aqueous sodium chloride solution, dried, filtered and evaporated to dryness to obtain 5 g of raw product. The latter was chromatographed over silica gel and was eluted with an 8-2-1 ethyl acetate-benzene-triethylamine mixture to obtain 3 g of 7-amino-6,7-dihydro [5H] benzocycloheptene in the form of a brown oil.
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