反应详情

To a cooled (-60°) solution of 4.9 g of 5-(5-methoxycarbonylpentyl)-imidazo[1,5-a]pyridine (obtained by esterification of 5-(5-carboxypentyl)-imidazo[1,5-a]pyridine of Example 2 with diazomethane in methylene chloride) in 140 ml of methylene chloride is added 40 ml of a 1.75 M solution of di-isobutyl aluminum hydride in hexane in a dropwise manner over a 20 minute period. On completion of the addition, the reaction is allowed to stir at -60° for a further 20 minutes. Then, 10 ml of methanol, followed by 100 ml of water, are added to quench the reaction. The reaction mixture is stirred at room temperature for 15 minutes, the methylene chloride layer is separated and the solvent evaporated under reduced pressure to yield 5-(5-formylpentyl)-imidazo[1,5-a]pyridine as an oil; NMR (CDCl3) 9.7 (m, 1H); IR (CH2Cl2) 1710 cm-1.

1. additionOn completion of the addition
2. additionare added
3. customto quench
4. customthe reaction
5. stirringThe reaction mixture is stirred at room temperature for 15 minutes
6. customthe methylene chloride layer is separated
7. customthe solvent evaporated under reduced pressure