Lithium Hydroxide → 5(S)-(Boc-Amino)-4(S)-hydroxy-6-phenyl-2(R)-[(p-benzyloxyphenyl)methyl]-hexanoic acid

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Reaction Steps

In analogy with Example 1i), 1.4 g (2.79 mmol) of 5(S)-[1(S)-(Boc-amino)-2-phenylethyl]-3(R)-[(p-benzyloxyphenyl)methyl]dihydrofuran-2-(3H)-one in 45 ml of dimethoxyethane and 23 ml of water are hydrolysed with 11 ml of a 1M lithium hydroxide solution. The reaction mixture, which has been partially evaporated, is poured onto a mixture of ice, 137 ml of sat. NH4Cl solution, 11 ml of 10% citric acid solution and 56 ml of methylene chloride, and methanol is added until the precipitated solid dissolves. The aqueous phase is extracted with 2 portions of methylene chloride/methanol, approximately 10:1, and the organic phases are washed with saline, dried with Na2SO4 and evaporated: tRet (I)=24.0 min; FAB-MS (M+H)+ =520.

Provenance & Evidence