p-Toluenesulfonic acid → 3-[[(S)-2-[[(1,1-Dimethylethoxy)carbonyl]amino]-1-oxo-3-phenylpropyl]amino]propanoic acid, phenylmethyl ester

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Reaction Conditions

Reaction Steps

2.03 g of TEA was added to a mixture of 5.84 g of Boc-Phe-OH and 7.03 g of TosOH.β-Ala-OBzl in 80 ml of dichloroethane. 4.54 g of DCC was added to the solution at 0 ° C. After stirring for 3 hrs at 0 ° C. and overnight at room temperature, precipitated DCUrea was filtered off and the solvent was distilled in vacuo. The residue was dissolved in ethyl acetate and the solution was washed with 10% citric acid aqueous solution, water, 5% sodium hydrogencarbonate aqueous solution and brine. After dehydration over sodium sulfate anhydride, the solvent was evaporated to give 8.36 g of Boc-Phe-β-Ala-OBzl; yield 98%.

Provenance & Evidence