Electric Literature of 628691-93-0 ,Some common heterocyclic compound, 628691-93-0, molecular formula is C6H3ClFNO2, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc., below Introduce a new synthetic route.
.-Benzyl-6-chloro-7-fluoro- 1 H-spiro [furo [3 ,4-c]pyridine-3 ,4′ -piperidin] – 1 -one2 3To a solution of 2,2,6,6-tetramethylpiperidine (72 g, 0.51 mol) in 200 ml of anhydrous THF under nitrogen at -78C was added n-BuLi (270 ml, 0.68 mol). After stirring for 0.5 h, the resulting mixture was added to a solution of 2-ch]oro-3-fluoropyridine-4-carboxylic acid (35 g, 0.2 mol) in 80 ml of anhydrous THF under nitrogen at -78C. After stirring for 3 h, the reaction mixture was added a solution of l-benzyl-piperidin-4-one (38 g, 0.20 mol) in 50 ml of THF under nitrogen at -78C. After stirring at -78C for 2 h, and room temperature for 1 h5 the reaction was quenched with 2 M aqueous hydrochloride (final pH = ca 2). The mixture was stirred at room temperature overnight, and the pH was adjusted to 9-10 with 2 M aq sodium hydroxide. The product was extracted with ethyl acetate (3x 500 mL), and the combined extracts were washed with brine, dried over Na2S0 j filtered and concentrated. The residue was purified by eluting on a silica gel column with PE: EtOAc = 3:1 to give the title compound.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route,628691-93-0, its application will become more common.
Reference:
Patent; MERCK SHARP & DOHME CORP.; MSD K.K.; LIN, Linus, S.; SUZUKI, Takao; WO2011/37771; (2011); A1;,
Pyridine – Wikipedia,
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