Sodium Carbonate → 5-Methoxy-2-tetralone

Participants

Reaction Conditions

Reaction Steps

A solution of 5-Methoxy-2-tetralone (X1) (150 g) in toluene (1000 mL) was prepared in a 2 L jacketed vessel equipped with a Dean-Stark condenser. To this solution was added propylamide (Y1) (150 g) and para-toluenesulfonic acid monohydrate (15 g). The mixture was refluxed for 24 hrs and reaction completion evaluated by hplc. The solution was cooled to 60° C. and 1% w/w Na2CO3 added (450 mL). In order to prevent product precipitation a further 300 mL of toluene was added. The phases were separated and the organic layer washed with water (450 mL). The organic layer was then cooled to 50° C. and aged to allow the product to crystallise. After crystallisation the slurry was further cooled to 5-10° C. and filtered. The filter cake was washed with toluene (2×150 mL), petroleum ether (150 mL) and the white crystalline needles were dried under vacuum at 25° C. to a constant weight of 124.4 g corresponding to compound (A2) (63.2% yield).

Provenance & Evidence