ETHYLATION OF 4-AMINO AND 4-OXO COMPOUNDS OF INDENO[1,2-B]PYRIDINE

Ethyl no-2-methyl-5H-indeno[1,2-b]pyridine-3-carboxylate (1) reacts wi th diethyl sulfate to yield the 4-ethylamino compound 12, whereas the reaction with ethyl iodide and potassium hydroxide under the condition s of phase transfer catalysis (PTC) affords the ethyl indene 14. Ethyl ethyl-4-oxo-5H-indeno[1,2-b]pyridine-3-carboxylate (2) and ethyl iodi de react, depending on the base used, to give the O-alkylated products 16 and 17 or the C,C,O-trialkylated substances 19 and 20. The structu re of the by-product 21 obtained under PTC conditions is elucidated.