Synthesis of Z-2-methyl-6-R-1,2,3,4-tetrahydro-4-quinolinecarboxylic acids

Bromination of methyl 2-methyl-6-R-1,2,3,4-tetrahydroquinoline-4-carboxylates

“…IR spectrum, ν, cm -1 : 3363 (NH), 1731 (СО). 1 To a solution of 1 g (5 mmol) of compound I in 15 ml of chloroform in the darkness at -20°С was added dropwise 1.68 g (0.53 ml, 10 mmol) of bromine in 7 ml of chloroform, and the mixture was stirred for 2 h at 20°С, then 35 ml of chloroform was added, the mixture was washed with 5% solution of NaHCO 3 , dried with anhydrous Na 2 SO 4 , the solvent was distilled off in a vacuum. Yield 0.5 g (19%), mp 169-172°С (EtOH).…”

“…In extension of the investigation of the properties of formerly synthesized 2-methyl-6-R-1,2,3,4-tetrahydroquinoline-4-carboxylic acids [1,2] we carried out the bromination of their methyl esters I and II. In the bromination of methyl ester I at -20°С dibromo derivative III was obtained.…”

“…IR spectrum, ν, cm -1 : 3016 (СH), 1731 (СО). 1 Bromination of ester II was carried out similarly to the synthesis of compound III. Esters V and VI were isolated by column chromatography om silica gel 60/200 (eluent petroleum ether-ethyl acetate, 40:1).…”

Synthesis of methyl 4-methyl-2-oxo-1,2,5,6-tetrahydro-4H-pyrrolo[3,2,1-ij]quinoline-6-carboxylate

“…Therefore, interest in development of methods for their preparation is quite understandable. Using previously synthesized substituted 1,2,3,4-tetrahydroquinoline-4-carboxylic acids [2] as starting compounds we obtained methyl 4-methyl-2-oxo-1,2,5,6-tetrahydro-4H-pyrrolo[3,2,1-ij]quinoline-6-carboxylate (I). Acylation of methyl 2-methyl-1,2,3,4-tetrahydroquinoline-4-carboxylate (III) with chloroacetyl chloride gave methyl 1-chloroacetyl-2-methyl-1,2,3,4-tetrahydroquinoline-4-carboxylate (II), and the latter underwent intramolecular alkylation according to Friedel-Crafts with formation of compound I which was isolated as individual Z isomer; its structure was proved by X-ray analysis [3].…”

Bromination of 2-phenyl-1,2,3,4-tetrahydroquinolines

“…In extension of the investigation of 2-R-1,2,3,4tetrahydroquinoline derivatives [13][14][15][16] we studied the bromination of 2-phenyl-and 2-phenyl-N-chloracetyl-1,2,3,4-tetrahydroquinoline with N-bromosuccinimide and bromine in different conditions. At the bromination of 2-phenyl-1,2,3,4-tetrahydroquinoline 4 with bromine in chloroform at the temperature of -20 о С and with N-bromosuccinimide at stirring for 3 h at room temperature in solvents mixture (chloroform-tetrachloromethane) along with the bromination the oxidation of the heterocyclic ring of DOI: 10 The structure of 3,6,8-tribromo-2-phenylquinoline 5 is established by the X-ray diffraction (XRD) method.…”