反应详情

Deprotect 3′-(4-ethoxyphenyl)-2,3,5,6-tetrahydro-[1,2′]bipyrazinyl-4-carboxylic acid t-butyl ester (1.80 g, 4.7 mmol) using 4 M HCl in 1,4-dioxane (38 mL) in DCM (100 mL). Concentrate and dissolve the residue in DCM and 10% aqueous sodium carbonate. Separate the layers and extract the aqueous layer with DCM (2×150 mL). Combine the organic layers, wash with saturated aqueous sodium chloride, dry (magnesium sulfate) and concentrate to give the title preparation (1.12 g, 84%). MS (ES): m/z=285 [M+H]+.

1. concentrationConcentrate
2. dissolutiondissolve the residue in DCM
3. customSeparate the layers
4. extractionextract the aqueous layer with DCM (2×150 mL)
5. washCombine the organic layers, wash with saturated aqueous sodium chloride
6. dry with materialdry (magnesium sulfate)
7. concentrationconcentrate
8. customto give the title
9. custompreparation (1.12 g, 84%)