5-tert-butyloxycarbonyl octahydrofuro[3,2-c]pyridine-7-carboxylic acid synthesis method

Abstract

The present invention relates to a 5-tert-butyloxycarbonyl octahydrofuro[3,2-c]pyridine-7-carboxylic acid synthesis method. In the prior art, the suitable industrial synthesis method does not exist. A purpose of the present invention is mainly to solve the technical problem in the prior art. The synthesis method comprises six steps, and specifically comprises that a compound 1 and 1-bromo-2-chloroethane are subjected to an alkylation reaction to obtain a compound 2, an intramolecular ring closure reaction is performed to generate a compound 3, the double bond of the compound 3 is subjected to hydrogenation reducing to obtain a compound 4, and the compound 4 is subjected to hydrolysis to obtain a compound 5. The reaction formula is defined in the specification.

Description

technical field

[0001] A method for synthesizing the compound 5-tert-butoxycarbonyl octahydrofuro[3,2-c]pyridine-7-carboxylic acid involved in the present invention. Background technique

[0002] Compound 5-tert-butoxycarbonyloctahydrofuro[3,2-c]pyridine-7-carboxylic acid (CAS: 1445951-87-0 and 1314399-22-8) and related derivatives in medicinal chemistry and organic synthesis has wide application. Currently, the synthesis of 5-tert-butoxycarbonyl octahydrofuro[3,2-c]pyridine-7-carboxylic acid is difficult. Therefore, it is necessary to develop a synthetic method with readily available raw materials, convenient operation, easy control of the reaction, and suitable overall yield. Contents of the invention

[0003] The purpose of this invention is to develop a kind of raw material that is easy to get, easy to operate, easy to control the reaction, and the synthesis of 5-tert-butoxycarbonyl octahydrofuran [3,2-c] pyridine-7-carboxylic acid with higher yield method. It main...

Examples

Embodiment 1

[0010] Example 1: Dissolve compound 1 (8.0g, 0.0295mol) in tetrahydrofuran (60mL), cool to -20 degrees Celsius, add potassium tert-butoxide (8.8g, 0.0738mol), stir for half an hour, then dropwise add Bromochloroethane (6.3g, 0.0443mol), after the addition was complete, the reaction was warmed to 15°C overnight. TLC (petroleum ether: ethyl acetate volume ratio=5 / 1, R f =0.5) showed that the reaction was complete, the reaction mixture was quenched with saturated ammonium chloride solution (30 mL), and extracted with ethyl acetate (20 mLx3). The organic phase was dried with anhydrous sodium sulfate and concentrated, the residue was purified by column chromatography, the eluent ratio was (petroleum ether: ethyl acetate volume ratio = 20 / 1), and compound 2 in yellow oil was obtained after removing the solvent (9.8 g), yield 100%.

[0011] Compound 2 (9.8g, 0.0295mol) was dissolved in tetrahydrofuran (80mL), sodium hydrogen (1.77g, 0.0441mol) was added under nitrogen protection at...

Embodiment 2

[0015] Example 2: Dissolve compound 1 (80g, 0.295mol) in tetrahydrofuran (600mL), cool to -20 degrees Celsius, add potassium tert-butoxide (88g, 0.738mol), stir for half an hour, then add bromochlorohydrin dropwise under nitrogen protection Ethane (63 g, 0.443 mol), after the addition was complete, the reaction was warmed to 15°C overnight. TLC (petroleum ether: ethyl acetate volume ratio=5 / 1, R f =0.5) showed that the reaction was complete, the reaction mixture was quenched with saturated ammonium chloride solution (300mL), and extracted with ethyl acetate (200mLx3). The organic phase was dried with anhydrous sodium sulfate and concentrated, the residue was purified by column chromatography, the eluent ratio was (petroleum ether: ethyl acetate volume ratio = 20 / 1), and compound 2 in yellow oil was obtained after removing the solvent (98g), yield 100%.

[0016] Compound 2 (98g, 0.295mol) was dissolved in tetrahydrofuran (800mL), sodium hydrogen (17.7g, 0.441mol) was added un...

Embodiment 3

[0020] Example 3: Dissolve compound 1 (400g, 1.475mol) in tetrahydrofuran (4.0L), cool to -20 degrees Celsius, add potassium tert-butoxide (440g, 3.69mol), stir for half an hour, then add bromine dropwise under nitrogen protection Ethyl chloride (315g, 2.215mol), after the addition was complete, the reaction was warmed to 15°C overnight. TLC (petroleum ether: ethyl acetate volume ratio=5 / 1, R f =0.5) showed that the reaction was complete, the reaction mixture was quenched with saturated ammonium chloride solution (1.0L), and extracted with ethyl acetate (1.0Lx3). The organic phase was dried with anhydrous sodium sulfate and then concentrated, and the residue was purified by column chromatography, the eluent ratio was (petroleum ether: ethyl acetate volume ratio = 20 / 1), and compound 2 in yellow oil was obtained after removing the solvent (490 g), yield 100%.

[0021] Compound 2 (490g, 1.475mol) was dissolved in tetrahydrofuran (4.0L), sodium hydrogen (177g, 4.41mol) was adde...

technical field

[0001] A method for synthesizing the compound 5-tert-butoxycarbonyl octahydrofuro[3,2-c]pyridine-7-carboxylic acid involved in the present invention. Background technique

[0002] Compound 5-tert-butoxycarbonyloctahydrofuro[3,2-c]pyridine-7-carboxylic acid (CAS: 1445951-87-0 and 1314399-22-8) and related derivatives in medicinal chemistry and organic synthesis has wide application. Currently, the synthesis of 5-tert-butoxycarbonyl octahydrofuro[3,2-c]pyridine-7-carboxylic acid is difficult. Therefore, it is necessary to develop a synthetic method with readily available raw materials, convenient operation, easy control of the reaction, and suitable overall yield. Contents of the invention

[0003] The purpose of this invention is to develop a kind of raw material that is easy to get, easy to operate, easy to control the reaction, and the synthesis of 5-tert-butoxycarbonyl octahydrofuran [3,2-c] pyridine-7-carboxylic acid with higher yield method. It main...

Examples

Embodiment 1

[0010] Example 1: Dissolve compound 1 (8.0g, 0.0295mol) in tetrahydrofuran (60mL), cool to -20 degrees Celsius, add potassium tert-butoxide (8.8g, 0.0738mol), stir for half an hour, then dropwise add Bromochloroethane (6.3g, 0.0443mol), after the addition was complete, the reaction was warmed to 15°C overnight. TLC (petroleum ether: ethyl acetate volume ratio=5 / 1, R f =0.5) showed that the reaction was complete, the reaction mixture was quenched with saturated ammonium chloride solution (30 mL), and extracted with ethyl acetate (20 mLx3). The organic phase was dried with anhydrous sodium sulfate and concentrated, the residue was purified by column chromatography, the eluent ratio was (petroleum ether: ethyl acetate volume ratio = 20 / 1), and compound 2 in yellow oil was obtained after removing the solvent (9.8 g), yield 100%.

[0011] Compound 2 (9.8g, 0.0295mol) was dissolved in tetrahydrofuran (80mL), sodium hydrogen (1.77g, 0.0441mol) was added under nitrogen protection at...

Embodiment 2

[0015] Example 2: Dissolve compound 1 (80g, 0.295mol) in tetrahydrofuran (600mL), cool to -20 degrees Celsius, add potassium tert-butoxide (88g, 0.738mol), stir for half an hour, then add bromochlorohydrin dropwise under nitrogen protection Ethane (63 g, 0.443 mol), after the addition was complete, the reaction was warmed to 15°C overnight. TLC (petroleum ether: ethyl acetate volume ratio=5 / 1, R f =0.5) showed that the reaction was complete, the reaction mixture was quenched with saturated ammonium chloride solution (300mL), and extracted with ethyl acetate (200mLx3). The organic phase was dried with anhydrous sodium sulfate and concentrated, the residue was purified by column chromatography, the eluent ratio was (petroleum ether: ethyl acetate volume ratio = 20 / 1), and compound 2 in yellow oil was obtained after removing the solvent (98g), yield 100%.

[0016] Compound 2 (98g, 0.295mol) was dissolved in tetrahydrofuran (800mL), sodium hydrogen (17.7g, 0.441mol) was added un...

Embodiment 3

[0020] Example 3: Dissolve compound 1 (400g, 1.475mol) in tetrahydrofuran (4.0L), cool to -20 degrees Celsius, add potassium tert-butoxide (440g, 3.69mol), stir for half an hour, then add bromine dropwise under nitrogen protection Ethyl chloride (315g, 2.215mol), after the addition was complete, the reaction was warmed to 15°C overnight. TLC (petroleum ether: ethyl acetate volume ratio=5 / 1, R f =0.5) showed that the reaction was complete, the reaction mixture was quenched with saturated ammonium chloride solution (1.0L), and extracted with ethyl acetate (1.0Lx3). The organic phase was dried with anhydrous sodium sulfate and then concentrated, and the residue was purified by column chromatography, the eluent ratio was (petroleum ether: ethyl acetate volume ratio = 20 / 1), and compound 2 in yellow oil was obtained after removing the solvent (490 g), yield 100%.

[0021] Compound 2 (490g, 1.475mol) was dissolved in tetrahydrofuran (4.0L), sodium hydrogen (177g, 4.41mol) was adde...

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