Method for catalytic synthesis of iminodibenzyl

Abstract

The invention discloses a preparation method of iminodibenzyl. The method utilizes 2, 2-diaminobibenzyl as a raw material to realize catalytic synthesis of iminodibenzyl. The preparation method comprises filling a fixed bed reactor with a H3PO4 / SiO2. Al2O3 catalyst, carrying out heating to 280 to 370 DEG C, introducing high temperature water vapor into the heated liquid 2, 2-diaminobibenzyl raw material so that bubbles are produced at the bottom and bring out the raw material, introducing water vapor mixed gas with the raw material into and through a fixed bed reaction pipe with the H3PO4 / SiO2. Al2O3 catalyst so that the raw material undergoes a deamination and loop closing reaction in the catalyst bed to produce a desired product, and precipitating the vapor-carried desired product in a solid form in a condenser pipe. The preparation method has an iminodibenzyl single-pass yield of 100%, realizes continuous synthesis for 3 months without replacement of a catalyst and has an iminodibenzyl yield of 98% or more.

Description

technical field

[0001] The invention relates to a method for preparing iminodibenzyl, specifically a method for synthesizing iminodibenzyl by catalyzing 2,2-diaminobibenzyl. Background technique

[0002] Iminodibenzyl is a very important drug synthesis intermediate, which can be used to produce carbamazepine, an analgesic and antispasmodic drug, and carbamazepine, an antiepileptic drug. Its main synthetic route is shown in the following formula: 2,2-diaminobibenzyl is used as raw material, and under the catalysis of a catalyst, iminodibenzyl is catalyzed under certain conditions.

[0003]

[0004] At present, the industrial catalytic synthesis of iminodibenzyl has the following methods:

[0005] 1. Catalytic deoxidation method

[0006] Literature (Molecular Catalysis, Gu Yusheng, Suo Jishuan, 2009, 23, 541-544) reported a method using γ-Al 2 o 3 As a catalyst, combined with γ-Al 2 o 3 The surface acidity characteristics of the surface, the method of preparing iminod...

Examples

Embodiment Construction

[0017] One, catalyst preparation embodiment

[0018] Weigh 500 g of amorphous silicon-aluminum molecular sieve microspheres with a silicon-aluminum ratio of 10:1, add them to 1 L of concentrated phosphoric acid, stir and soak at room temperature for 6 hours. The impregnated silica-alumina molecular sieve was filtered out, dried, and calcined in a muffle furnace at 600° C. for 4 hours. After roasting, continue soaking in phosphoric acid, drying and roasting, this process is repeated three times to increase the loading capacity of phosphoric acid. After the catalyst is prepared, it is crushed into particles with a particle diameter of 1-2 mm.

[0019] Two, catalytic deamination embodiment

[0020] Fill the pulverized catalyst into a fixed-bed reaction tube with a diameter of 1.5 cm and a length of 20 cm and heat it to 300°C. The flow rate of distilled water is 5mL / min through the constant liquid sampling pump, and it is input into the high-temperature steam generator, and is ...

technical field

[0001] The invention relates to a method for preparing iminodibenzyl, specifically a method for synthesizing iminodibenzyl by catalyzing 2,2-diaminobibenzyl. Background technique

[0002] Iminodibenzyl is a very important drug synthesis intermediate, which can be used to produce carbamazepine, an analgesic and antispasmodic drug, and carbamazepine, an antiepileptic drug. Its main synthetic route is shown in the following formula: 2,2-diaminobibenzyl is used as raw material, and under the catalysis of a catalyst, iminodibenzyl is catalyzed under certain conditions.

[0003]

[0004] At present, the industrial catalytic synthesis of iminodibenzyl has the following methods:

[0005] 1. Catalytic deoxidation method

[0006] Literature (Molecular Catalysis, Gu Yusheng, Suo Jishuan, 2009, 23, 541-544) reported a method using γ-Al 2 o 3 As a catalyst, combined with γ-Al 2 o 3 The surface acidity characteristics of the surface, the method of preparing iminod...

Examples

Embodiment Construction

[0017] One, catalyst preparation embodiment

[0018] Weigh 500 g of amorphous silicon-aluminum molecular sieve microspheres with a silicon-aluminum ratio of 10:1, add them to 1 L of concentrated phosphoric acid, stir and soak at room temperature for 6 hours. The impregnated silica-alumina molecular sieve was filtered out, dried, and calcined in a muffle furnace at 600° C. for 4 hours. After roasting, continue soaking in phosphoric acid, drying and roasting, this process is repeated three times to increase the loading capacity of phosphoric acid. After the catalyst is prepared, it is crushed into particles with a particle diameter of 1-2 mm.

[0019] Two, catalytic deamination embodiment

[0020] Fill the pulverized catalyst into a fixed-bed reaction tube with a diameter of 1.5 cm and a length of 20 cm and heat it to 300°C. The flow rate of distilled water is 5mL / min through the constant liquid sampling pump, and it is input into the high-temperature steam generator, and is ...

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