Water → 6-(5-morpholino-3-pyridyl)-3,4-dihydro-2H-1,8-naphthyridine-1-carboxamide

Participants

Reaction Conditions

Reaction Steps

In a sealed tube which contains the crude 6-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-3,4-dihydro-2H-[1,8]naphthyridine-1-carboxylic acid amide (generated according to the procedure for Step 3 of Example 16 in 5 ml 1,4-dioxane, 0.78 mmol) is added 4-(5-bromo-pyridin-3-yl)-morpholine (228 mg, 0.94 mmol), Na2CO3 (166 mg, 1.56 mmol) and water (1.0 ml). The mixture is bubbled with Argon for 5 min. Then PdCl2(DPPF) DCM complex (64 mg, 0.078 mmol) is added. The mixture is then bubbled with Argon for 5 min. The cap is sealed and the mixture is heated at 90° C. in oil bath for 1 h. The reaction mixture is cooled to room temperature. The reaction mixture is filtered through diatomaceous earth and washed with DCM. The filtrate is partitioned between water and DCM. The aqueous phase is extracted with DCM. The combined DCM phases are concentrated. The crude is purified by flash silica gel column (MeOH/DCM 0 to 4% gradient, then 4%). The fractions which contain the desired product are combined, concentrated and further purified by C-18 prep HPLC (MeCN with 0.1% TFA/Water with 0.1% TFA, 20 ml/min, 0 to 45% gradient over 10 min run). The desired fractions are combined and basified by 1N Na2CO3 to pH=10, and are extracted by DCM. The DCM phases are combined and concentrated under vacuum to obtain 60 mg of the title compound.

Provenance & Evidence