Phosphate → HCID 552105, compound

Participants

Reaction Steps

To a solution of 17.38 g of p-toluenesulfonic acid maintained between -18° C.-25° C., 23.9 mL of ethylvinyl ether in. 125 mL of dichloromethane is added in drops over a period of 1-1.5 hours. When the addition is complete, the mixture is stirred for another 1 hour. To the above cold solution 250 mL of pH 7 phosphate buffer is added and the cold mixture is poured into a mixture of 800 mL of ethyl acetate and 200 mL of water. The organic layer is removed and the aqueous layer is extracted with 2×200 mL of ethyl acetate. The combined layers were washed with brine, dried over anhydrous MgSO4 and evaporated to give S-(1-ethoxy)ethylmercaptoacetic acid 11 in 100 mL of dry tetrahydrofuran were added 4.85 g of N-hydroxysuccinimide and 8.7 g of N,N'-dicyclohexycarbodiimide. The mixture is stirred for 2-3 hours. TLC in EtOAc:hexanes:acetic acid 49:50:1 (p-anisaldehyde stain) showed the completion of the reaction. Dicyclohexylurea is removed by filtration and the filtrate is evaporated. The oily residue is dissolved in 50 mL of ethyl acetate and washed with water. The solution is dried over anhydrous MgSo4 and evaporated and the product is purified by silica gel flash column chromatography.

Provenance & Evidence