Tetrabutylammonium Fluoride → 5-(4-{2(R)-[2(R)-(3-Chlorophenyl)-2-hydroxyethyl-amino]propoxy}benzyl)thiazolidine-2,4-dione

88 g of tetrabutylammonium fluoride were added to a solution of 46.2 g of 5-(4-{2(R)-[2(R)-(3-chlorophenyl)-2-t-butyldimethylsilyloxyethylamino]propoxy}benzyl)thiazolidine-2,4-dione [prepared as described in Preparation 3]in 500 ml of tetrahydrofuran, whilst ice-cooling, and the mixture was stirred at room temperature for 15 hours. At the end of this time, the tetrahydrofuran was distilled off under reduced pressure. The residue was then mixed with water and extracted with ethyl acetate. The extract was washed-with a saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate, after which the solvent was distilled off under reduced pressure. The residue was then purified by column chromatography through silica gel, using a 5:1 by volume mixture of ethyl acetate and ethanol as the eluent, to obtain the title compound in the form of crude crystals. These crystals were then recrystallized from a mixture of ethyl acetate and ethanol to give 27.1 g of the title compound melting at between 100° C. and 112° C.

1. customprepared
2. temperaturecooling
3. distillationAt the end of this time, the tetrahydrofuran was distilled off under reduced pressure
4. additionThe residue was then mixed with water
5. extractionextracted with ethyl acetate
6. dry with materialdried over anhydrous sodium sulfate
7. distillationafter which the solvent was distilled off under reduced pressure
8. customThe residue was then purified by column chromatography through silica gel
9. additionby volume mixture of ethyl acetate and ethanol as the eluent

ORD record

ord-f3f2c5f83bd44ce99e9b041396dfb9b4

Source dataset

uspto-grants-1995_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05436257