To a solution of 13 (550 mg, 2.226 mmol) in toluene 25 mL was added 3-chloro-4-(trifluoromethyl)benzaldehyde 90 (464.2 mg, 2.226 mmol). PTSA (846.7 mg, 4.452 mmol) was added to the reaction, and stirred at 120° C. for 6 h, then diluted with ethyl acetate and washed with water (3×25 mL). The organic layer was dried over sodium sulphate and concentrated to get the crude compound 91 which was purified through flash chromatography by using 100-200 mesh silica gel. The compound was eluted at 30% ethyl acetate in hexane to afford yellow coloured solid compound (E)-2-(3-chloro-4-(trifluoromethyl)benzylidene)-6-methoxy-5-morpholino-2,3-dihydro-1H-inden-1-one 91.
