Diethyl Ether → [8-(4-Methoxy-phenyl)-1,4-dioxa-spiro[4.5]dec-8-yl]-dimethylamine

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Reaction Steps

Magnesium (3.65 g, 150 mmol) and an iodine crystal were provided in a nitrogen atmosphere and heated. Abs. ether (10 mL) was then added and a solution of 4-bromoanisole (18.8 mL, 150 mmol) in abs. ether (150 mL) was added in drops so that the ether lightly boiled. The solution formed was subsequently stirred for 1 h at RT and then mixed in drops with a solution of 8-dimethylamino-1,4-dioxa-spiro[4.5]decane-8-carbonitrile (10.5 g, 50.0 mmol) in abs. THF (100 mL), and the solution heated to 37-40° C. until boiling during the addition. A precipitate separated out and the batch was stirred overnight at RT. The solution was mixed with NH4Cl solution with ice cooling, the phases were separated, the aqueous phase extracted three times with ether, the combined organic phases washed with saturated NaCl solution and water, dried over Na2SO4 and concentrated to low volume in a vacuum. Flash chromatography of the residue with ethyl acetate/methanol (20:1→9:1→4:1→1:4→MeOH) gave the desired product.

Provenance & Evidence