In 1960,Reimlinger, Hans K. published 《Bisdiazoalkanes. II. The preparation of bispyrazolylalkane derivatives》.Chemische Berichte published the findings.Application In Synthesis of Methyl 1H-pyrazole-3-carboxylate The information in the text is summarized as follows:
cf. CA 53, 15060d. Alkynes, activated by α-CO groups, yielded with bisdiazoalkanes in solution or in situ ringsubstituted bispyrazolylalkanes. The reaction of nascent monodiazoalkanes with (CCO2Me)2 (I) gave, depending on the reaction conditions, the expected di-Me pyrazoledicarboxylate (II) together with di-Me bis(dicarbomethoxypyrazolyl)succinate (III) or its alkylated derivatives The III was formed from I with II by a Michael-type addition reaction; the addition which occurred on the pyrazole-N was reversible. HCCCO2Me (IV) yielded in an analogous reaction an acrylic ester derivative, substituted on the pyrazole-N. Na2SO4 (1 g.) and 47 mmoles I in 200 cc. dry Et2O treated at -5° with 1 g. K2CO3, the mixture cooled to -10°, treated dropwise below -5° with stirring with 94 mmoles N,N’-dinitroso-N,N’-diacetylalkylenediamine in 50 cc. absolute MeOH, the mixture stirred 5 hrs. with cooling, filtered, the residue washed with H2O, and recrystallized from hot H2O gave the corresponding bis(4,5-dicarbomethoxy-3-pyrazolyl)alkane (V); the filtrate neutralized with AcOH and evaporated in vacuo gave a dark brown N-free sirup; in this manner were prepared the following V (number of C atoms of alkane chain, m.p., and % yield given): 1, 179-81°, 22; 2 (VI), 199°, 22; 4, 180-1°, 16; 6, 107°, 20; 8, 98-9°, 30. The pentamethylene derivative could only be obtained as a crude brown sirup. VI (2 g.) in 200 cc. 2N H2SO4 refluxed 2 days, cooled, and filtered yielded 1 g. hygroscopic 1,2-bis(4,5-dicarboxy-3-pyrazolyl)ethane (VII), decomposed at 260°. VII (1 g.) added in small portions to excess CH2N2-Et2O, the mixture treated with AcOH, and evaporated yielded 1 g. N,N’-di-Me derivative of VI. [(CH2)4NH2]2 (50 g.) in 200 cc. C6H6 treated dropwise with 40 cc. Ac2O, the mixture stirred 15 min., and filtered gave 76% [AcNH(CH2)4]2 (VIII), m. 130° (Me2CO). VIII in AcOH-Ac2O treated with nitrous gases, poured onto crushed ice, and filtered yielded 96% [AcN(NO)(CH2)4]2 (IX), m. 55-6°. IV (6 g.) in 200 cc. Et2O treated dropwise at 0° with (CH2CH2CHN2)2 in Et2O and filtered after 1 hr. gave 70% 1,4-bis(5-carbomethoxy-3-pyrazolyl)butane, m. 183-4° (H2O). (BzC)2 (10 g.) in 100 cc. Et2O treated in the usual manner with IV yielded 11.8 g. (crude) 1,4-bis(5-benzoyl-3-pyrazolyl)butane, m. 191° (MeOH). I (14.2 g.) and 2 g. Na2SO4 added to 100 cc. Et2O, the mixture cooled to 0°, treated with 2 g. K2CO3 and then during 15 min. with stirring with 10 g. [AcN(N0)CH2]2 (X) in 75 cc. MeOH, and filtered after 2 hrs. yielded 500 mg. 4,4′,5,5-tetracarbomethoxy-3,3′-bipyrazolyl, needles, m. 170° (2:1 C6H6-EtOH). Dry Et2O (100 cc.), 2 g. K2CO3, 2 g. Na2SO4, and 11.3 g. AcN(NO)Me (XI) treated dropwise at 10-15° with 14.2 g. I in 50 cc. MeOH, filtered, and the residue treated with hot H2O left 3.4 g. di-Me α,α’-bis[3,4(4,5)-dicarbomethoxy-1-pyrazolyl]succinate (XII), decomposed at 191°; the Et2O solution evaporated and the residue recrystallized from the aqueous filtrate gave 9 g. di-Me 3,4-dicarbomethoxypyrazole (XIII), m. 141°. A similar run in which MeOH was added to a mixture of I, XI, K2CO3, and Na2SO4 in Et2O yielded 93% XII. A run in which I in MeOH was added to XI, K2CO3, and Na2SO4 in Et2O gave 20% XII and 48% XIII; the XI in MeOH added to I, K2CO3, and Na2SO4 in Et2O gave 74% XII; the I and XI in MeOH added to K2CO3 and Na2SO4 in Et2O yielded 25% XII and 42% XIII. I (2.9 g.) and 3.7 g. XIII in 70 cc. Et2O and 35 cc. MeOH refluxed 4 hrs. and evaporated, the viscous residue heated 1 day on the water bath, diluted with Et2O, filtered, the residue digested with boiling H2O, and filtered left 300 mg. XII. I (4.6 g.) and 4 g. XIII in 50 cc. MeOH and 100 cc. Et2O treated with a few drops concentrated NaOMe in MeOH and filtered after 2 days yielded 4.3 g. XII. XII (5 g.) in 50 cc. MeOH, containing a small piece of Na, neutralized immediately with AcOH, evaporated, the residue treated with petr. ether, filtered, and the filtrate evaporated gave a few drops of oily I; the petr. ether-insoluble solid (1.5 g.) was XIII, m. 141°. XII (3 g.) heated slowly under N to 190°, kept 1 min. at 190°, cooled, treated with boiling H2O, filtered, and the filtrate cooled gave 0.2 g. XIII; 0.2 g. 2nd crop; the H2O-insoluble solid treated with AcOH gave 2.1 g. XII. XII (10 g.) in 200 cc. 2N HNO3 refluxed 2 days, filtered hot, and cooled gave hydrated 3,4-dicarboxypyrazole (XIV), needles, decomposed at 263-4°, which dried 1 day over P2O5 in a desiccator gave XIV.H2O and dried further at 80° over P2O5 gave XIV; the aqueous acidic filtrate extracted 3 days with Et2O, the extract evaporated, and the residue treated with the calculated amount of CH2N2 yielded XIII. XIV and XIII treated with excess CH2N2 yielded the N-Me derivative of XIII, b11 124-5°. XIII (1 g.) in 25 cc. ClCO2Et refluxed 1.5 hrs., evaporated in vacuo, and cooled yielded 77% N-MeO2C derivative of XIII, m. 73° (H2O). I (3.4 g.) and 3.55 g. I. in 50 cc. Et2O treated with a few drops of concentrated NaOMe-MeOH and filtered after standing overnight yielded 0.5 g. di-Me α,α’-di(1-pyrazolyl)succinate (XV), m. 139° (hot H2O). Pyrazole K derivative in dry C6H6 from 5 g. pyrazole treated slowly dropwise with 5 g. (CHClCO2Me)2 in 50 cc. C6H6, the mixture refluxed 0.5 hr., washed with H2O, and worked up yielded 22.4% XV. I (10 g.) and 1 g. Na2SO4 added to 200 cc. dry Et2O, the mixture cooled to -2°, treated with 1 g. K2CO3 and then dropwise during 2.5 hrs. with 6.9 g. X in 130 cc. absolute MeOH, the mixture cooled to -10°, and filtered gave 25% 1-(1,2-dicarbomethoxyvinyl)-4,4′,5,5-tetracarbomethoxy-3,3′-bipyrazolyl, m. 220° (H2O). XI (13 g.) and 14.2 g. I in 50 cc. Et2O treated with 2 g. Na2SO4 and 3 g. K2CO3, the mixture treated dropwise at 15-20° with 25 cc. MeOH, and filtered after 2 hrs. yielded 7 g. di-Me α,α’bis[5(3)-methyl-3,4(4,5)-dicarbomethoxy-1-pyrazolyl] succinate (XVI), decomposed at 143-4°; 0.7 g. 2nd crop; the aqueous filtrate neutralized with AcOH and evaporated, the residue extracted with C6H6, and the oily residue from the extract digested with petr. ether yielded 15% 5(3)-methyl-3,4(4,5)dicarbomethoxypyrazole (XVII), m. 106°, also obtained from I and MeCHN2. AcN(NO)Pr (10 g.) in 50 cc. Et2O treated with 2 g. Na2SO4 and 3 g. K2CO3 and then during 2 hrs. with stirring at 10-15° with 9.7 g. I in 50 cc. MeOH, the mixture filtered after standing overnight, neutralized with AcOH, evaporated in vacuo, and the residue reprecipitated from dioxane with H2O yielded 3.3 g. 5(3)-Et analog of XVI, prisms, decomposed at 123.5° (MeOH); the aqueous dioxane filtrate evaporated and distilled gave 3 g. 5(3)-Et analog of XVII, b0.05 150-2°. AcNHC18H37 in 200 cc. Ac2O-AcOH treated 7 hrs. with nitrous gases and poured onto ice and H2O yielded 94.5% AcN(NO)C18H37 (XVIII), lemon-yellow, m. 43-4° (Me2CO). I (7.1 g.) and 19 g. XVIII in 50 cc. Et2O treated with 1 g. Na2SO4 and 1.5 g. K2CO3 and then during 2 hrs. with 25 cc. MeOH, the mixture filtered after 3 hrs., the residue dissolved in MeOH, and cooled to -40° yielded 64% 1-(N-octadecyldicarbomethoxypyrazolyl)heptadecane, m. 47°. Ba(OH)2 (3 g.) in 50 cc. Et2O and 50 cc. MeOH treated during 2 hrs. with 15.5 g. I and 18 g. AcN(NO)Bu below 25°. the mixture filtered, neutralized with AcOH, evaporated in vacuo, the red-brown viscous residue (21 g.) diluted with Et2O, filtered, evaporated, and the viscous residue (17 g.) fractionated gave 12 g. 5(3)-Pr analog of XVII, b0.0001 140°. I (14.2 g.) and 15 g. AcN(NO)CH2CH2OMe gave in the usual manner 21.5 g. (crude) 5(3)-MeOCH2CH2 analog of XVII, b0.0001 154-6°. IV (8.4 g.) in 100 cc. Et2O and 12 g. XI in 50 cc. MeOH yielded with 2 g. Na2SO4 and 2 g. K2CO3 9.5 g. 3(5)-carbomethoxypyrazole (XIX), m. 142° (MeOH). XI (9.5 g.) in 50 cc. MeOH and 13.3 g. IV in 50 cc. Et2O with 2 g. Na2SO4 and 2 g. K2CO3 gave Me β-(3)-carbomethoxy-1-pyrazolyl]acrylate (XX), m. 110-10.5° (H2O). IV (1.7 g.) and 2.5 g. XIX in 30 cc. MeOH treated with 3 drops concentrated NaOMe-MeOH, the mixture heated 1 hr. on the water bath, and kept 7 days gave 300 mg. XX, m. 110°. After reading the article, we found that the author used Methyl 1H-pyrazole-3-carboxylate(cas: 15366-34-4Application In Synthesis of Methyl 1H-pyrazole-3-carboxylate)
Methyl 1H-pyrazole-3-carboxylate(cas: 15366-34-4) belongs to pyrazoles. The application of pyrazole derivatives in the development of anticancer agents has been thoroughly investigated and verified. Moreover, the medicinal features of a number of natural products incorporating pyrazole moiety such as pyrazofurin, pyrazofurin B, pyrazole-3(5)-carboxylic acid and 4-methylpyrazole-3(5)-carboxylic acid have been reported.Application In Synthesis of Methyl 1H-pyrazole-3-carboxylate
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics