2-Benzoxazolinone

2-Benzoxazolinone or 2-(3H)-benzoxazolone is an organic compound used as a precursor to several insecticides. It has quite an interesting structure (in my opinion anyway). I plan to use 2-Benzoxazolinone to make 2-aminophenol.

2-Benzoxazolinone can be made from salicylamide. I tried this out.

To a 225ml conical flask, I added 3.4g of crude salicylamide and 100ml of water. I then placed this in an ice bath to cool down. To a separate vessel, I added 50ml of water, 3g of sodium hydroxide and 13ml 4% sodium hypochlorite bleach. The sodium hydroxide prevents ring chlorination. Anyway, once the salicylamide mixture had cooled to 7 C, I started to slowly add the bleach mix in 5ml portions with strong stirring. It's very important that the temperature is low. Once the bleach addition was complete, I added 15ml 10% sodium hydroxide solution and heated the mixture to 70 C for 30 minutes. After this I chilled the mixture down again in the ice bath.

Once the temperature had fallen to 8 C, I added 25ml of 33% hydrochloric acid. A fluffy brown precipitate of 2-benzoxazolinone formed. I filtered the product off and dried it. I was left with 1.8g of 2-benzoxazolinone which is a 54% yield. Not a bad day's work!

For how the reaction works see this
http://www.sciencemadness.org/talk/files.php?pid=416184&aid=42761