In general, if the atoms that make up the ring contain heteroatoms, such rings become heterocycles, and organic compounds containing heterocycles are called heterocyclic compounds. An article called Methoxyindoles and their derivatives, published in 1924, which mentions a compound: 67929-86-6, Name is Methyl 5-methoxyindole-2-carboxylate, Molecular C11H11NO3, Electric Literature of C11H11NO3.
2,5-O2N(HO)C6H3Me, m. 128°, was obtained in 58 g. yield (together with 42 g. of 4,5-O2N(HO)C6H3Me) by slowly adding 140 g. m-HOC6H4Me in 140 g. AcOH to a stirred mixture of 200 g. HNO3 (d. 1.5) and 400 g. AcOH at -8° to -5°, and removing the 4-NO2 derivative by steam distillation Me2SO4 (252 g.) added to 153 g. 2,5-O2N(HO)C6H3Me and 46 g. Na in 750 cc. MeOH gave a 90% yield of 2,5-O2N(MeO)C6H3Me (I), m. 55°. 2-Nitro-5-methoxyphenylpyruvic acid (II), yellow, m. 128° (phenylhydrazone, yellow, m. 151-2° (decomposition)), results in 51 g. yield from 50 g. of I and 63 g. (CO2Et)2 added to a suspn. of 35 g. EtONa in 300 cc. dry Et2O. Oxidation of II by H2O2 in 2% NaOH gave 2-nitro-5- methoxyphenylacetic acid, m. 176°. Reduction of II in NH4OH by FeSO4 gave a 73% yield of 5-methoxyindole-2-carboxylic acid (III), m. 196-7° (evolution of gas). Warmed with Ehrlich’s reagent, a deep pink color is produced, which fades on cooling. Me ester, m. 177°. Et ester, m. 156°. 2,3-O2N(MeO)C6H3Me, (CO2Et)2 and KOEt in Et2O give a 75% yield of 2-nitro-3-methoxy-phenylpyruvic acid (IV), pale yellow, m. 161-2°, or yellow with 0.5 AcOH of crystallization, m. 118-45°. The EtOH solution gives a deep green color with FeCl3, destroyed by mineral acids. Phenylhydrazone, yellow, m. 159° (decomposition). Oxidation of IV gives 2-nitro-3-methoxyphenylacetic acid, m. 137-8°, while reduction with FeSO4 and NH4OH gives 7-methoxyindole-2-carboxylic acid (V), m. 182° and decomposes on continued heating. Et ester, m. 114°. Me ester, m. 120°. 2-Nitro-6-methoxyphenylpyruvic acid (VI), yellow, m. 47-55°; phenylhydrazone, yellow, m. 173-4° (decomposition). Oxidation with H2O2 gives 2-nitro-6-methoxyphenylacetic acid, yellow, m. 172°, while reduction of VI gave 4-methoxyindole-2-carboxylic acid (VII), m. 234-5°, in 63% yield. Ehrlich’s reagent gives a purple color, which disappears on cooling. Me ester, m. 143.5°. Et ester, m. 161.5°. p-MeOC6H4NHNH2 (VIII), best prepared by diazotizing p-MeOC6H4NH2 and reducing with SnCl2 in concentrated HCl, m. 65°; yield, 44%. α-Ketobutyric acid p-methoxy-phenylhydrazone (IX), yellow, m. 105°. o-Methoxyphenylhydrazone (X), pale yellow, m. 112°. The action of concentrated H2SO4 on IX (or the components in EtOH) gives 5-methoxyskatole-2-carboxylic acid (XI), m. 200-1° (decomposition), isolated as the Et ester, m. 151-2°; Me ester, m. 156°. In the same way X gave 7-methoxyskatole-2-carboxylic acid (XII), m. 222-3°, isolated as the Me ester, m. 144-15°, the yield of the acid being only 23%. A by-product of this reaction is Et ketobutyrate phenylhydrazone, yellow, m. 59-60°. III, changed to the acid chloride by PCl5 in AcCl, this dissolved in CHCl3 and treated with MeNHCH2CH(OMe)2, gave 5-methoxyindole-2-carboxydimethylacetalyl-methylamide, m. 159°. This is converted by warming with saturated alc. HCl at 40-50° for 15 min. into a mixt, of about equal amounts of 10-methoxy-3-keto-4-methyl-3,4-dihydro-4-carboline (XIII), m. 280°, has a distinct blue fluorescence in the solid state, gives a yellow HCl salt, which is dissociated by H2O and gives no color with Ehrlich’s reagent or with vanillin and HCl in the cold; the alc. solution has a striking lilac fluorescence; and 10- methoxy-5-keto-4- methyl-4,5-dihydroindole-1,4-diazine (XIV), m. 243°, gives a greenish blue color with Ehrlich’s reagent, fading to a pale yellow on cooling and becoming green on boiling, and gives an intense purple color with vanillin and HCl; the EtOH solution has a very faint blue fluorescence which is not increased by adding HCl. 5-Methoxyindole-2-carboxyacetalylamide m. 151-2°, results from the chloride of III and H2NCH2CH(OEt)2; Ehrlich’s reagent gives a purple solution, becoming intense blue on warming, while NaNO2 produces a green color in the cold. Vanillin and HCl produce a deep pink which becomes intense bluish violet on the addition of NaNO2 and warming. The action of alc. HCl gives 10-methoxy-5-keto-4,5-dihydroindole-1,4-diazine (XV), sinters 265°, m. 280°. 5-Methoxyindole-2-carboxydimethylacetalylamide, m. 154°, and with alc. HCl gives XV. 5-Methoxyindole-2-carboxyacetalylmethylamide, m. 127°, is formed from the chloride of III and MeNHCH2CH(OEt)2; with alc. HCl it yields about equal quantities of XIII and XIV. 7- Methoxyindole-2-carboxydimethylacetalylmethylamide, obtained only as a sirup, gives with alc. HCl a mixture of approx. 4 parts 12-methoxy-3-keto-4-methyl-3,4-dihydro-4-carboline, pale yellow, m. 250°, yielding a golden-yellow HCl salt, and 1 part 12-methoxy-5-keto-4-methyl-4,5-dihydroindole-l,4-diazine, m. 135°, which gives a blue color with vanillin and HCl and a green color with Ehrlich’s solution 4-Methoxyindole-2-carboxydimethylacetalylmethylamide, m. 112°, which, with alc. HCl, gave 9-methoxy-3-keto-4-methyl-3,4-dihydro-4-carboline, m. 250°, and yields a sparingly soluble yellow HCl salt. The mother liquors gave a green color with vanillin and HCl but the diazine was not isolated. When XII was subjected to the above reactions, a compound C14H13O2N2Cl, m. 190°, was obtained, which was unchanged by treatment with 10% MeOH-KOH for 10 min. and is probably 9-chloro-12-methoxy-5-keto-4,7-dimethyl-4,5-dihydroindol-l,4-diazine. III decomposes vigorously when heated to 205-210°, yielding 5-methoxyindole (XVI), b17 176-8° m. 55°, acquires a pink tint which slowly darkens on standing, is only slightly volatile with steam (1 g. per l. of H2O), colors a pine shaving moistened with HCl reddish violet, gives a purple precipitate with concentrated HNO3 and NaNO2. Picrate, bright red, m. 145°. 1-Ac derivative (XVII), b25 210-1°, m. 80-1°. Nitration of the Ac derivative gave a mixture of an a-NO2 derivative, light brown, m. 149°, soluble in EtOH, and the b-NO2 derivative, brown, m. 213-4°, the a-derivative predominating. Hydrolysis gave a- and b-nitro-5-methoxyindoles, yellow, m. 144° (mixture m. about 112°); the a-form gives an orange-purple color with a pine stick, the b-form a deep purple. The a-form gives a pale red color with Ehrlich’s reagent, not affected by addition of NaNO2, while the b-form develops a red color only after addition of NaNO2. XVI, treated with CHCl3 and EtOH-KOH, yields a mixture of 5-methoxyindole-3-aldehyde, m. 178°, and 3-chloro-6-methoxyquinoline, m. 73-4°, separated by steam distillation XVI was also synthesized as follows: 4-Methoxy-2-aldehydophenylglycineamide oxime, yellow, m. 196° (decomposition) was obtained in 70% yield from 5,2-MeO(H2N)C6H3CH:NOH and ClCH2CONH2 (formyl derivative, bright yellow, m. 223°); on hydrolysis yields 4-methoxy-2-aldehydophenylglycine oxime, pale yellow, m. 178°; with saturated H2SO3 this is changed to 4-methoxy-2-aldehydophenylglycine, bright orange, m. 183° (decomposition) (phenylhydrazone, yellow, m. 175-6°) which yields XVII on boiling with AC2O and AcONa. V, decomposed at 230-3°, gives 73% of 7-methoxyindole, b17 157°, b21 159-61°, slowly turns brown on keeping, fairly volatile with steam (2 g. per 500 cc. H2O), gives a deep mauve pine-shaving reaction, gives a yellow color with Ehrlich’s reagent, deepening to orange-red on warming and to a deep reddish purple on addition of dilute NaNO2. Picrate, red, m. 156°. With alc. KOH and CHCl3 this yields 7-methoxyindole-3-aldehyde, m. 159-60°, and 3-chloro-8-methoxyquinoline, m. 84.5°; the yield of both products was small. VII, at 245-50°, gives 4-methoxyindole, m. 69.5°, (picrate, red, m. 159-60°) gives a deep purple pine-shaving reaction and a reddish purple color with Ehrlich’s reagent. XI decomposes at 210° and gives 75% of 5-methoxyskatole, m. 66°, apparently non-volatile with steam, gives a red pine-shaving reaction and a reddish purple color with Ehrlich’s reagent. Picrate, dark red, m. 151-2°. XII similarly yields 7-methoxyskatole, b20 170° (picrate, brownish red, m. 156°). The pine-shaving reaction is a deep purplish red; Ehrlich’s reagent gives no color in the cold; on warming a reddish purple color develops. The K derivative of II gives with Me2SO4 2-nitro-α-methoxycinnamic acid (XVIII), pale yellow, m. 164-5°. Na salt, yellow. Me ester, pale yellow, m. 67°; the Et ester appears to be an oil. Oxidation of XVIII gives o-O2NC6H4CHO. Reduction of XVIII with FeSO4 and NH4OH gives the 2-amino derivative, pale yellow, crystallines with 2AcOH and m. 167°. Me ester, yellow, m. 60-1°. The acid readily loses MeOH, forming indole-2-carboxylic acid, m. 203-4° (heating above its m. p., solution in cold concentrated H2SO4 at room temperature for 16 hrs., boiling with 10% HCl or reduction of XVIII with FeSO4 and NH4OH and boiling the reaction product for 24 hrs.). 2-Nitro-α,3-dimethoxycinnamic acid, from IV, as above, m. 202° (decomposition), and reduced to the 2-amino derivative, m. 139°, and decomposing above its m. p. to give V.
After consulting a lot of data, we found that this compound(67929-86-6)Electric Literature of C11H11NO3 can be used in many types of reactions. And in most cases, this compound has more advantages.
Reference:
Isoquinoline – Wikipedia,
Isoquinoline | C9H7N – PubChem