Potential hydroxy heterocyclic compounds are heated in HMPA at 220–230° for 20 min-15 h. The OH Group is thereby replaced by a dimethylamino-group and the yields for the reactions are indicated for the following compounds: 2-Dimethylamino-quinoline (79%); 2- dimethylamino-lepidine (77%); 2-dimethylamino-benzo [b] furan (47%); 2-dimethylamino-1- methyl-indole (68%); 2-di-methylamino-thiophene (3%); 2-dimethylamino-5-methyl- ...