Hydrochloric Acid → 2-Chloro-6-ethoxybenzylamine

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Reaction Steps

To a solution of 2-chloro-6-ethoxybenzonitrile, 135, (93.2 g, 0.513 mol) in THF (350 mL) at room temperature under a dry nitrogen atmosphere was added borane in THF (1.0 M, 620 mL, 0.62 mol). The resulting mixture was heated to reflux for 3 hours and then cooled to room temperature. Water (250 mL) was added very slowly to the solution allowing for the evolution of hydrogen. Concentrated HCl (50 mL) was then added over several minutes and the solution was heated to 50° C. for 2 hours. The mixture was cooled and partitioned between chloroform and water. The aqueous layer was washed 6 times with chloroform. The combined organic fractions were washed with HCl (1 M) and this organic layer was discarded. Chloroform was added to the combined aqueous layers and solid KOH was added until the aqueous phase was basic (pH>9). The aqueous layer washed with chloroform an additional five times. The organic fractions were combined and washed with water, brine, and dried over MgSO4 and silica gel (2 g). This mixture was filtered and the filtrate was concentrated under reduced pressure to give 2-chloro-6-ethoxybenzylamine, 136, (60.1 g, 64% yield) as a light yellow oil.

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