反应详情

A solution of 785 mg (1.71 mmole) of (S)-4-(benzyloxycarbonyl)-1-(diphenylacetyl)piperazine-2carboxylic acid (from Step A) in 25 ml of methanol was treated with 800 mg of 10% Pd/C and the mixture was hydrogenated at 40 psi at 25° C. with rocking for 4 hours. The mixture was filtered and the catalyst was washed with 4×30 ml of acetic acid. All organic phases were combined, concentrated in vacuo, redissolved in 100 ml of water and reconcentrated in vacuo to leave 404 mg (73%) of waxy solid which was homogeneous by TLC (4:1:1 n-butyl alcohol-acetic acid-water, Rf =0.55).

1. filtrationThe mixture was filtered
2. washthe catalyst was washed with 4×30 ml of acetic acid
3. concentrationconcentrated in vacuo
4. dissolutionredissolved in 100 ml of water
5. customto leave 404 mg (73%) of waxy solid which