Triphenylphosphine → 3-[(Benzenesulfonyl(methoxycarbonylmethyl)amino)methyl]-6-methylpyridine-2-carboxylic acid isopropyl ester

Participants

Reaction Steps

According to the conditions reported by Anthony et al (WO 02/30931 A2) for the preparation of 3-[(benzenesulfonyl(methoxycarbonylmethyl)amino)methyl]pyridine-2-carboxylic acid isopropyl ester, a solution of diisopropyl azodicarboxylate (1.07 g, 5.30 mmol) in THF (5 mL) was added dropwise over 40 min to a stirred solution of 3-hydroxymethyl-6-methyl-pyridine-2-carboxylic acid isopropyl ester (739 mg, 3.53 mmol), N-(phenylsulphonyl)glycine methyl ester (810 mg, 3.53 mmol) and triphenylphosphine (1.39 g, 5.30 mol) in THF (15 mL) The resulting solution was then left to stir at room temperature overnight. The reaction mixture was concentrated to give crude 3-[(benzenesulfonyl(methoxycarbonylmethyl)amino)methyl]-6-methylpyridine-2-carboxylic acid isopropyl ester as a golden syrup. This was used in the subsequent step without further purification.—Selected 1H NMR (CDCl3): δ 4.73 (s, 2H), 4.00 (s, 2H), 3.54 (s, 3H), 2.70 (s, 3H).

Provenance & Evidence