The mixture was aged at 90 C for 24 h without stirring. The solid product was recovered by filtration; it was washed with water several times and once with ethanol, then it was dried at 60 C.
The mixture was aged at 90 C for 24 h without stirring. The solid product was recovered by filtration; it was washed with water several times and once with ethanol, then it was dried at 60 C.