step 3 a mixture consisting of 6 fluoro 7 methylindole 3 2 allyl ethanol prepared in step 2 11 0 g 0 048 mol 3 methoxy 2 pentenoic acid methyl ester 11 g bf 3 et 2 o 1 ml and dichloromethane 500 ml was stirred at room temperature for 2 hours diluted with dichloromethane washed with 5 nahco 3 water dried mgso 4 and concentrated to give 21 g of oil this was washed through a silica gel column using hexane followed by 5 ethyl acetate hexane preparative liquid chromatography on a waters assoc prep 500 instrument using 3 5 ethyl acetate hexane as eluant afforded the esters 5 g of isomer a and 6 5 g of isomer b isomer a ester was hydrolyzed by refluxing with a mixture of koh 5 g methanol 500 ml and water 10 ml for 2 5 hours the reaction was concentrated diluted with water and extracted with ether the aqueous phase was acidified with 5 hcl and extracted with chloroform 3 u00d7 200 ml the combined extracts were washed with water dried mgso 4 and concentrated to give 3 g of solid acid recrystallization from toluene petroleum ether afforded 2 0 g 12 6 yield of title compound m p 159 u00b0 160 u00b0 c ______________________________________nmr dmso d sub 6 no of protons type chemical shift u03b4 ______________________________________3 ch sub 3 0 72 t j 7 2 ch sub 2 1 95 m 3 ch sub 3 2 35 s 2 u2550 ch sub 2 5 1 m 1 h c u2550 c 5 8 m 2 aromatic.