Download (4Mb) - Etheses - Saurashtra University

Chapter – 4 Studies on different types of reactions…..
4.9.4 GENERAL PROCEDURE FOR THE PREPARATION OF DNJ-701 TO
DNJ-705
METHOD – (A) CONVENTIONAL APPROACH
0.01 mole of 1-(2, 6-dichlorophenyl)-2-indolinone was dissolved into 30
ml of methanol into 100 ml round bottom flask. 0.01 mole of an appropriately
substituted pyrazole-4-carboxaldehyde was added to the above flask along
with catalytic amount of piperidine. The reaction mixture was refluxed on
water bath for 5-7 hours. The progress and the completion of the reaction
were checked by silica gel-G F254 thin layer chromatography using hexane :
ethyl acetate (6 : 4) as a mobile phase. After the reaction to be completed, the
reaction mixture was cooled to room temperature and the product was
separated by filtration. The product was washed with methanol and dried to
give desired product in moderate yield which was recrystallized by DMF.
(Physical data of the synthesized end products are summarized in the table
4.10.1)
METHOD – (B) MICROWAVE APPROACH
0.01 mole of 1-(2, 6-dichlorophenyl)-2-indolinone was dissolved into 20
ml of dimethylformamide into 100 ml microwave flask. 0.01 mole of an
appropriately substituted pyrazole-4-carboxaldehyde was added to the above
flask along with catalytic amount of piperidine. The reaction mixture was
irradiated under microwave irradiation using Qpro-M microwave synthesizer
for the desired time at 400 W. The progress and the completion of the
reaction were checked at the interval of every one min. by silica gel-G F254
thin layer chromatography using hexane : ethyl acetate (6 : 4) as a mobile
phase. After the reaction to be completed, the reaction mixture was cooled
and scratched into 30 ml of methanol. The separated product was filtered off
and washed with methanol and it was dried to give desired product in good
yield which was recrystallized by DMF. (Physical data of the synthesized end
products are summarized in the table 4.10.1)
Department of Chemistry, Saurashtra University, Rajkot – 360 005 226