Reaction #2254171

Reaction equation

sodium borohydride

ethanol

Ethyl 7-hydroxychromen-4-one-2-carboxylate

calcium chloride

Sodium borohydride

→

2-methoxy-7-hydroxy-4H-chromen-4-one

Conditions

Workup

1. 1
   Temperatureagain cooled
2. 2
   workup.STIRRINGThe mixture is stirred overnight at RT

Procedure

Ethyl 7-hydroxychromen-4-one-2-carboxylate (2 g, 8.538 mmol) and granulated and dried calcium chloride (1 g, 9.01 mmol) are initially introduced, and ethanol (absolute, 40 ml) is added. Sodium borohydride (1.33 g, 35.157 mmol) is subsequently added in portions with ice cooling. The reaction mixture is stirred at RT for 2 hours, then again cooled using an ice bath, and sodium borohydride (0.45 g, 11.895 mmol) is again added. The mixture is stirred overnight at RT.

Source