METHYL 5-FORMYL-2-THIOPHENECARBOXYLATE

Step 1. Methyl 5-formyl-2-thiophenecarboxylateA mixture of 5-formyl-2-thiophene carboxylic acid (2.34 g, 15 mmol) and sodium carbonate (5.57 g, 52.5 mmol) in DMF (25 ml) at 25 To a solution of 4-methylmorpholine N-oxide (0.449 g, 3.83 mmol) in MeCN (5 mL) at 0 °C, in presence of molecular sieves 3Å, compound 13 in MeCN (0.300 g, 1.28 mmol) was added. Reaction mixture was kept stirring at 25 °C for 12 h and then filtered and purified by column chromatography on silica gel (EtOAc/n-hexane 1:20) to obtain the title compound (yield 70percent);The compound 24 (3 g, 17.4 mmol) was dissolved in acetone and an excess of MN02 was added thereto. After 2days of the reaction time, the reaction solution was filtered under reduced pressure with Celite545 and then an exraction process was conducted with acetone sufficiently. The filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (hexane: ethyl acetate= 2: 1) to obtain the compound 25 (2.2 g, yield 75percent) 1H NMR (300MHZ, CDC13) 9.98 (s, 1H), 7.85-7. 84 (d, J=3.9Hz, 1H), 7.76-7. 75 (d, J=3.9Hz, 1H). 13C NMR (300MHZ, CDC13) 183.02, 160.99, 139.75, 136.36, 135.09, 132.28, 51.96.In a reaction vessel, 5-formylthiophene-2-carboxylic acid (0.50 g), 4-dimethylaminopyridine (0.11 g), methanol (0.87 g) and chloroform (12 mL) were added, It was cooled to 5 ° C.To this was added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.74 g).After stirring at room temperature for 1 hour, 3 mol / L hydrochloric acid (8 mL) was added.The reaction solution was extracted with chloroform, The organic layer was washed with saturated brine.The organic phase was dried over anhydrous sodium sulfate, The solvent was distilled off to obtain a crude product.This was purified with a silica gel column (chloroform)To give a yellow product (5-formylthiophene-2-carboxylic acid methyl ester, 0.45 g).In a reaction vessel, Pyrrole (1.26 g), 2-formyl-5-hexylthiophene (2.77 g), In a reaction vessel, 5-formylthiophene-2-carboxylic acid (0.50 g), 4-dimethylaminopyridine (0.11 g), methanol (0.87 g) and chloroform (12 mL) were added, It was cooled to 5 ° C.To this was added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.74 g).After stirring at room temperature for 1 hour, 3 mol / L hydrochloric acid (8 mL) was added.The reaction solution was extracted with chloroform, The organic layer was washed with saturated brine.The organic phase was dried over anhydrous sodium sulfate, The solvent was distilled off to obtain a crude product.This was purified with a silica gel column (chloroform)To give a yellow product (In a reaction vessel, 5-formylthiophene-2-carboxylic acid (0.50 g), 4-dimethylaminopyridine (0.11 g), methanol (0.87 g) and chloroform (12 mL) were added, It was cooled to 5 ° C.To this was added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.74 g).After stirring at room temperature for 1 hour, 3 mol / L hydrochloric acid (8 mL) was added.The reaction solution was extracted with chloroform, The organic layer was washed with saturated brine.The organic phase was dried over anhydrous sodium sulfate, The solvent was distilled off to obtain a crude product.This was purified with a silica gel column (chloroform)To give a yellow product (To a solution of 4-methylmorpholine N-oxide (0.449 g, 3.83 mmol) in MeCN (5 mL) at 0 °C, in presence of molecular sieves 3A, compound 13 in MeCN (0.300 g, 1.28 mmol) was added. Reaction mixture was kept stirring at 25 °C for 12 h and then filtered and purified by column chromatography on silica gel (EtOAc/n-hexane 1:20) to obtain the title compound (yield 70percent);

Molecular Weight:170.19
XLogP3:1.6
Hydrogen Bond Acceptor Count:4
Rotatable Bond Count:3
Exact Mass:170.00376522
Monoisotopic Mass:170.00376522
Topological Polar Surface Area:71.6
Heavy Atom Count:11
Complexity:169
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes