6-Methylcoumarin → 6-Bromomethyl-chromen-2-one

Participants

Reaction Steps

To a solution of 500 g (31.25 mmoles) of 6-methylcoumarin in 200 ml CCl4 is added 5.56 g (31.25 mmoles) of NBS. This solution is subjected to a sunlamp at reflux for 41/2 hours. After cooling, the reaction mixture is filtered and the filtrate concentrated in vacuo to yield a solid which upon trituration with ethyl acetate affords 6-bromomethylcoumarin which is used directly in the next step.

Provenance & Evidence