HCID 22917831, compound → Tetra-n-butylammonium 1-(3-nitrophenyl)ethanesulphonate

Participants

Reaction Steps

5.2 g of potassium nonafluorobutanesulphonate dissolved in 12 cm3 of acetone are added to a solution of 10.5 g of a mixture of the A and B forms (about 15/85 in moles) of N-benzylquininium 1-(3-nitrophenyl)ethanesulphonate in 16 cm3 of acetone. The insoluble product is filtered off and then dissolved in 9 cm3 of water. 8.4 cm3 of an aqueous 1N hydrochloric acid solution and 1.15 g of (R)-(-)-phenylglycinol are added. The solution obtained is concentrated to dryness under reduced pressure (2.7 kPa) at 50° C. The residue obtained is extracted with 3 times 15 cm3 of acetonitrile under reflux. The organic phases are combined and concentrated to about 7 cm3 ; after cooling, the crystals are filtered off and dissolved in 7.5 cm3 of an aqueous 1N sodium hydroxide solution. The solution obtained is washed with 8 times 25 cm3 of diethyl ether, after which 60 cm3 of an aqueous 0.5M solution of potassium dihydrogenphosphate and 2.3 g of tetra-n-butylammonium hydrogensulphate are added. The mixture is extracted with 3 times 30 cm3 of methylene chloride. The combined organic phases are dried over magnesium sulphate and concentrated to dryness under reduced pressure (2.7 kPa) at 40° C. 2.8 g of the laevorotatory isomer of tetra-n-butylammonium 1-(3-nitrophenyl)ethanesulphonate are thus obtained in the form of an oil which is used as such in the subsequent syntheses.

Provenance & Evidence