[摘要]:An improved protocol for the preparation of 1-oxo-1,2,3,4-tetrahydroacridine-9-carboxylic acid derivatives via Pfitzinger condensation under acidic conditions is described, it provides a simple one-pot synthetic method for some useful 1-oxo-1,2,3,4-tetrahydroacridine-9-carboxylic acids which could not be synthesized successfully by Pfitzinger reactions under usual conditions using the corresponding isatins and 1,3-diketones. All the synthesized compounds are characterized by spectral data.