Methanol → 4-[2-(4-chloromethyl-benzoylamino)-4-methoxy-benzothiazol-7-yl]-3,6-dihydro-2H-pyridine-1-carboxylic acid tert-butyl ester

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Reaction Steps

To a solution of 0.35 g (0.97 mMol) 4-(2-amino-4-methoxy-benzothiazol-7-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid tert-butyl ester in 20 ml dioxane were added 0.2 ml triethyl amine, 12 mg DMAP and 0.238 g (1.26 mMol) 4-chloromethyl-benzoyl chloride, dissolved in 1 ml of dioxane. The reaction mixture was heated to reflux for 3 h. Then 5 ml methanol were added. The solvent was evaporated to dryness, the residue taken up in ethyl acetate and washed with water and brine. The organic phase was dried over sodium sulfate and evaporated to dryness in vacuo. The residue was subjected to column chromatography (ethyl acetate/hexane 1:1) to yield 0.37, (74%) 4-[2-(4-chloromethyl-benzoylamino)-4-methoxy-benzothiazol-7-yl]-3,6-dihydro-2H-pyridine-1-carboxylic acid tert-butyl ester as a white foam. ES-MS m/e (%): 514 ([M+H]+, 100).

Provenance & Evidence