反应详情

2,3-Dihydro-benzo[1,4]dioxine-6-carbaldehyde (188 mg, 1.14 mmol, 1.8 eq) is added at room temperature to a stirred solution of the trifluoroacetic acid salt of 6-methoxy-quinoline-3-carboxylic acid trans-4-amino-cyclohexylmethyl ester (200 mg, 0.64 mmol, 1.0 eq) in 1,2-dichloroethane (10 mL), followed by sodium triacetoxyborohydride (1.35 g, 6.36 mmol, 10.0 eq). After 18 hours stirring at room temperature, the reaction mixture is extracted with dichloromethane (3×10 mL) and a saturated sodium hydrogen carbonate aqueous solution (10 mL). The combined organic layers are dried over sodium sulfate, filtered and concentrated to give a residue that is purified by preparative HPLC to afford 6-methoxy-quinoline-3-carboxylic acid trans-4-[(2,3-dihydro-benzo[1,4]dioxin-6-ylmethyl)-amino]-cyclohexylmethyl ester as a white powder (123 mg, 40% yield).

1. extractionthe reaction mixture is extracted with dichloromethane (3×10 mL)
2. dry with materialThe combined organic layers are dried over sodium sulfate
3. filtrationfiltered
4. concentrationconcentrated
5. customto give a residue that
6. customis purified by preparative HPLC