反应详情

97.0 g (343 mmol) of the compound from Example III are initially introduced into 500 ml of pyridine, and 31.3 ml (343 mmol) of phosphorus oxychloride are added at 0° C., while stirring. The mixture is heated slowly, and is finally boiled under reflux for 1 hour. After cooling to room temperature, ether and an amount of 1M hydrochloric acid such that the pH of the aqueous phase is 1.5 are added. The organic phase is washed three more times with 1M sulphuric acid, dried with sodium sulphate and evaporated on a rotary evaporator and the residue is freed from the residual solvent under a high vacuum.

1. additionare added at 0° C.
2. temperatureThe mixture is heated slowly
3. temperatureunder reflux for 1 hour
4. additionare added
5. washThe organic phase is washed three more times with 1M sulphuric acid
6. dry with materialdried with sodium sulphate
7. customevaporated on a rotary evaporator