阅读说明：本技术 一种利用微通道反应装置连续制备联苄的方法 (Method for continuously preparing bibenzyl by using microchannel reaction device ) 是由 李玉光 季栋 张锴 孟繁荣 花加伟 郭凯 于 2020-10-26 设计创作，主要内容包括：本发明提供了一种利用微通道反应装置连续制备联苄的方法,以甲苯为反应原料,在催化剂、氧化剂及溶剂的存在下,在微通道反应装置内连续反应,通过自由基自身偶联反应得到联苄Ⅱ；该方法提供了一种新的联苄制备方法,工艺操作简便、安全、高效,反应条件温和。所述反应过程如反应式所示：(The invention provides a method for continuously preparing bibenzyl by utilizing a microchannel reaction device, which takes methylbenzene as a reaction raw material, continuously reacts in the microchannel reaction device in the presence of a catalyst, an oxidant and a solvent, and obtains bibenzyl II through self-coupling reaction of free radicals; the method provides a novel method for preparing bibenzyl, and has the advantages of simple, convenient, safe and efficient process operation and mild reaction conditions. The reaction process is shown as a reaction formula:)

1. A method for continuously preparing bibenzyl by using a microchannel reaction device is characterized in that methylbenzene is used as a reaction raw material and continuously reacted in the microchannel reaction device to obtain bibenzyl; the reaction comprises the following steps:

(1) dissolving toluene and a catalyst in a solvent A to obtain a homogeneous solution A; dissolving an oxidant in a solvent B to obtain a homogeneous solution B;

(2) pumping the homogeneous phase solutions A and B obtained in the step (1) into a micro mixer in a micro-channel reaction device respectively, mixing, and injecting into the micro-channel reactor for reaction;

(3) collecting reaction liquid flowing out of the microchannel reactor to obtain bibenzyl;

the reaction formula is as follows:

2. the method of claim 1, wherein in step (1), the catalyst is any one or more of N-iodosuccinimide, tetramethylammonium iodide, tetrabutylammonium bromide and iodine.

3. The method according to claim 1, wherein in the step (1), the oxidizing agent is any one or more of tert-butyl hydroperoxide, hydrogen peroxide, tert-butyl peroxybenzoate and di-tert-butyl peroxide; the solvent A and the solvent B are respectively and independently one or a combination of more of acetonitrile, dimethyl sulfoxide, dioxane, N-dimethylformamide, dichloroethane and water.

4. The method according to claim 1, wherein in the step (1), the concentration of the toluene in the homogeneous solution A is 0.05-0.3 mmol/mL; the concentration of the catalyst in the homogeneous phase solution A is 0.01-0.03 mmol/mL; the concentration of the oxidant in the homogeneous solution B is 0.1-0.4 mmol/mL.

5. The method according to claim 1, wherein in the step (2), the flow rate of the homogeneous solutions A and B pumped into the microchannel reactor is 0.2ml/min to 1 ml/min; the reaction temperature is 30-80 ℃.

6. The method of any one of claims 1 to 5, wherein the micro-reaction device comprises a pump A, a pump B, a micro-mixer, a micro-channel reactor and a receiver, wherein the pump A and the pump B are connected to the micro-mixer in parallel, and the micro-mixer, the micro-channel reactor and the receiver are connected in series, wherein the connection is via a pipe.

7. The process of claim 6 wherein the microchannel reactor has a reaction volume of 5ml to 10ml and a coil internal diameter of 0.5mm to 1 mm.

Technical Field

The invention belongs to the field of organic synthesis, and particularly relates to a method for continuously preparing bibenzyl by using a microchannel reaction device.

Background

Bibenzyl compounds are commonly found in many natural products and have potential biological and agricultural activity. Some bibenzyl derivatives are used as starting materials for the synthesis of highly useful drug molecules and therefore attract much attention from chemists.

At present, the preparation method of bibenzyl mainly comprises the following steps: (1) self-coupling of benzyl halides to synthesize bibenzyls, as described in the literature (org. lett.,2014,16, 3756); (2) nickel-catalyzed olefin hydrogenation reactions, as described in the literature (chem. eur. j.2020,26, 6113-; (3) precious metal-catalyzed aluminum powder is used for reducing tolane to synthesize bibenzyl, which can be seen in the literature (Tetrahedron 72(2016)6943e 6947); (4) titanium dioxide photoredox catalysis utilizes radical coupling of phenylacetic acid, as can be seen in the literature (org. lett.2014,16, 5394-5397). Although the existing preparation routes of bibenzyl are numerous, most of the methods use toxic metals, and have complicated reaction conditions and long reaction time, so that the industrial application of bibenzyl is limited.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the problems of long reaction process period and metal catalysis requirement of the traditional reaction system are solved, and a novel method for synthesizing bibenzyl is provided.

In order to solve the technical problems, the invention adopts the technical scheme that:

a method for continuously preparing bibenzyl by using a microchannel reaction device takes methylbenzene as a reaction raw material, and continuously reacts in the microchannel reaction device to obtain bibenzyl; the reaction comprises the following steps:

(1) dissolving toluene and a catalyst in a solvent A to obtain a homogeneous solution A; dissolving an oxidant in a solvent B to obtain a homogeneous solution B;

(2) pumping the homogeneous phase solutions A and B obtained in the step (1) into a micro mixer in a micro-channel reaction device respectively, mixing, and injecting into the micro-channel reactor for reaction;

(3) collecting reaction liquid flowing out of the microchannel reactor to obtain bibenzyl;

the reaction formula is as follows:

in the step (1), the catalyst is any one or more of N-iodosuccinimide, tetramethyl ammonium iodide, tetrabutyl ammonium bromide and iodine, and tetrabutyl ammonium iodide is preferred.

In the step (1), the oxidant is any one or more of tert-butyl hydroperoxide, hydrogen peroxide, tert-butyl peroxybenzoate and di-tert-butyl peroxide, and preferably tert-butyl hydroperoxide; the solvent A and the solvent B are respectively and independently one or a combination of more of acetonitrile, dimethyl sulfoxide, dioxane, N-dimethylformamide, dichloroethane and water, and preferably the dimethyl sulfoxide and the water are used as mixed solvents with the volume ratio of 1: 1.

In the step (1), the concentration of toluene in the homogeneous solution A is 0.05-0.3 mmol/mL; the concentration of the catalyst in the homogeneous phase solution A is 0.01-0.03 mmol/mL; the concentration of the oxidant in the homogeneous solution B is 0.1-0.4 mmol/mL.

In the step (2), the flow rate of the homogeneous solutions A and B pumped into the microchannel reactor is 0.2 mL/min-1 mL/min, preferably 0.5 mL/min; the reaction temperature is 30-80 ℃, and preferably 40 ℃.

Preferably, the micro-reaction device comprises a pump A, a pump B, a micro mixer, a micro channel reactor and a receiver, wherein the pump A and the pump B are connected to the micro mixer in a parallel manner, and the micro mixer, the micro channel reactor and the receiver are connected in a series manner, and the connection is realized through a pipeline.

Preferably, the reaction volume of the microchannel reactor is 5ml to 10ml, and the inner diameter of a coil of the reactor is 0.5mm to 1 mm; most preferably, the microchannel reactor has a reaction volume of 10ml and a coil internal diameter of 0.5 mm.

Preferably, the pumps A and B are injection pumps.

Has the advantages that: the invention adopts a microchannel reaction device, the reaction time is shortened to ten minutes from the traditional dozens of hours, the product yield is higher, and the reaction efficiency is obviously improved; the method does not need to add a metal catalyst, is simple and convenient to operate and has low cost; the invention continuously reacts through the injection pump and the microchannel reaction device, the preparation process is easy to operate and control, the safety is high, the reaction condition is mild, and the invention has better industrial amplification potential.

The microchannel reactor used in the invention is a microchannel reactor with small channel diameter and high heat transfer efficiency. The method for quickly synthesizing the bibenzyl by using the microchannel reactor greatly improves the yield, reduces side reactions, is favorable for amplification reaction, and has safe, efficient and simple reaction process. The microchannel reactor is a three-dimensional structural element that can be used for chemical reactions, fabricated with a fixed matrix by means of special microfabrication techniques. The microchannel reactor has very small channel size and channel diversity, and fluid flows, mixes and reacts in the channels, so that the micro-structured chemical equipment has extremely large specific surface area (surface area/volume), thereby bringing the advantages of extremely large mass transfer and heat transfer efficiency, namely, the accurate control of reaction temperature and the instantaneous mixing of reaction materials in accurate proportion, which are all key to the improvement of yield, selectivity, safety and product quality.

Drawings

FIG. 1 is a schematic flow diagram of a microchannel reactor apparatus according to the present invention.

FIG. 2 is a hydrogen spectrum of bibenzyl prepared in the examples.

FIG. 3 is a carbon spectrum of bibenzyl prepared in the examples.

Detailed Description

The invention will be better understood from the following examples. However, those skilled in the art will readily appreciate that the description of the embodiments is only for illustrating the present invention and should not be taken as limiting the invention as detailed in the claims.

Using the apparatus diagram of fig. 1, the following steps are followed: (1) respectively adding the solution A and the solution B which are prepared in proportion into injection pumps a and B; (2) injecting the mixture into a microchannel reaction device by an injection pump according to a certain proportion for mixing and reacting; (3) the reaction temperature of the microchannel reactor is controlled by an oil bath pan; (4) collecting the effluent reaction liquid, adding saturated sodium thiosulfate for quenching, adding ethyl acetate for extraction and separation, and calculating the product yield by an HPLC method; and measuring the product yield by a high performance liquid chromatography, and separating by column chromatography to obtain the target product.

Example 1

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 82% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

¹H NMR(400MHz,Chloroform-d)δ7.22–7.16(m,4H),7.11(td,J＝6.3,1.5Hz,6H),2.83(s,4H).

¹³C NMR(101MHz,Chloroform-d)δ140.73,127.41,127.29,124.87,36.90.

HRMS(TOF)m/z[M+H]⁺Calcd for C₁₄H₁₅ 183.1168 found 183.1165.

Example 2

Dissolving 1mmol (0.092g) of toluene and 0.1mmol (0.037g) of tetrabutylammonium iodide in 5mL of dimethyl sulfoxide and 5mL of water to obtain a homogeneous solution A, and adding the homogeneous solution A to a syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 70% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 3

1mmol (0.092g) of toluene and 0.3mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 77% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 4

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 1mmol TBHP (70%, 0.386g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 80% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 5

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 4mmol TBHP (70%, 0.257g) (t-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 72% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 6

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.2 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 25 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 63% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 7

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 1 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 5 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 61% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 8

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 30 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 75% by using an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 9

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 60 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 77% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 10

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 80 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 69% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 11

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 10mL of dimethyl sulfoxide to give a homogeneous solution A, which was added to syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) in 10mL dimethyl sulfoxide to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 48% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 12

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 5ml, and the reaction time is 5 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 70% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 13

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 30 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 80% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 14

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 1 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 62% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 15

Dissolving 1mmol (0.092g) of toluene and 0.2mmol (0.040g) of tetramethylammonium iodide in 5mL of dimethyl sulfoxide and 5mL of water to obtain a homogeneous solution A, and adding the homogeneous solution A into a syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 72% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 16

Dissolving 1mmol (0.092g) of toluene and 0.2mmol (0.064g) of tetrabutylammonium bromide in 5mL of dimethyl sulfoxide and 5mL of water to obtain a homogeneous solution A, and adding the homogeneous solution A into a syringe pump a; 2mmol TBHP (70%, 0.257g) (tert-butyl hydroperoxide) 5mL dimethyl sulfoxide and 5mL water to give a homogeneous solution B, which was added to syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 72% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 17

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; adding 2mmol of DTBP (0.292g) (di-tert-butyl peroxide) in 5mL of dimethyl sulfoxide and 5mL of water to obtain a homogeneous solution B, and adding the homogeneous solution B into a syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 82% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Example 18

1mmol (0.092g) of toluene and 0.2mmol (0.074g) of tetrabutylammonium iodide were dissolved in 5mL of dimethyl sulfoxide and 5mL of water to give a homogeneous solution A, which was added to syringe pump a; adding 2mmol TBPB (0.388g) (tert-butyl peroxybenzoate) 5mL dimethyl sulfoxide and 5mL water to obtain a homogeneous solution B, and adding the homogeneous solution B into a syringe pump B; the injection flow rates of the injection pumps a and b are both 0.5 ml/min; the reaction volume V of the microchannel reactor is 10ml, and the reaction time is 10 min; the inner diameter of the micro-channel reactor is 0.5 mm; the temperature of the microchannel reactor is 40 ℃; after one period of reaction in the microchannel reactor, collecting reaction liquid, calculating the product yield to be 82% by an HPLC method, and obtaining the bibenzyl after column chromatography separation.

Comparative example 1

1mmol (0.092g) of toluene, 0.2mmol (0.074g) of tetrabutylammonium iodide, 2mmol of TBHP (70%, 0.257g) (tert-butyl hydroperoxide), 10mL of dimethyl sulfoxide and 10mL of water were sequentially added to a 100mL eggplant-shaped flask, stirred at 40 ℃ for 6 hours, the reaction liquid was collected, the product yield was 62% by HPLC, and bibenzyl was obtained after column chromatography separation.