反应详情

To a solution of 4-(2-methoxy-ethyl)-piperidine-4-carboxylic acid ethyl ester (0.72 g) in methylene chloride (40 ml) was added at RT under an argon atmosphere DMAP (0.75 g) and then dropwise 2,2-dimethyl-propane-1-sulfonyl chloride (0.57 ml). The reaction mixture was stirred 12 h at RT then partitioned between AcOEt and aqueous 1M HCl, the layers were separated and the aqueous layer washed with 2M aqueous KHCO3 then dried over Na2SO4. The solvent was evaporated off, the residue purified by flash chromatography (AcOEt/heptane, gradient from 0 to 40%) to give the desired 1-(2,2-dimethyl-propane-1-sulfonyl)-4-(2-methoxy-ethyl)-piperidine-4-carboxylic acid ethyl ester (0.34 g) as a light yellow viscous oil.

1. customthen partitioned between AcOEt and aqueous 1M HCl
2. customthe layers were separated
3. washthe aqueous layer washed with 2M aqueous KHCO3
4. dry with materialthen dried over Na2SO4
5. customThe solvent was evaporated off
6. customthe residue purified by flash chromatography (AcOEt/heptane, gradient from 0 to 40%)