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the corresponding carbonyls and carboxylic acids in a continuous flow reactor (Fig.3). The continuous flow reactor has the ability to dissipate heat rapidly, and controls the temperature effectively. This continuous flow system provided the desired product in high production and great purity under room temperature13.

1.3 Grignard reagents
The reactions involving Grignard reagents need to be controlled by accomplishing at very low temperature in batch reactors. The continuous flow synthesis technology represents an innovative way to perform the reactions involving Grignard reagents at a temperate reaction condition, such as room temperature, which avoiding low-temptation regulation. Qiulin Deng et al. represented a new continuous flow synthesis method to synthesis 2, 4, 5-Trifluorobenzoic acid via the Grignard reagents reactions under a room temperature and an atmosphere pressure (Fig.4). The product 2, 4, 5-Trifluorobenzoic acid is obtained in high yield with great purity in micro reactors than batch reactors14.

E. Riva et al. set up a new protocol for performing the reaction of carbonyl compounds with Grignard reagents in a continuous flow system. This chemical reaction conditions were controlled at room temperature avoiding cryogenic temperatures. The production yields is excellent by using an optimized protocol. And this continuous flow system could be applied for the preparation an analgesic drug called Tramadol, which allowed the addition of Grignard reagents to the process under room temperature15.

2.Liquid-solid phase reaction
Recently, the isolated enzymes are used to replace toxic metal catalysts and develop a new effective process. Particularly, the isolated enzymes immobilized on the solid supports are more suitable for the environmental medical reactions. Many studies indicate the polymerization reactions using solid-supported enzymes in the micro reactors has more advantages compared to the one in batch reactors, such as specific temperature control, safer and less wastes pollution. Santanu Kundu used micro reactors to catalyze ring-opening polymerization ofε-caprolactone to polycaprolactone via solid-supported enzymes. By using the continuous flow synthesis technology, the polymerization is more quick and efficient compared to the batch synthesis. And the micro reactors also enable to improve the reaction condition and rapid production compared to the batch reactors. It seems the similar continuous flow system can apply on the other enzyme-solid chemical reactions16. Gjergji Shore et al. used Pd thin films as an excellent catalyst for Suzuki-Miyama and Heck reactions in continuous flow system. If the reactions were run in batch reactors, the reactions will never flow through the microwave chamber and have no productions17.

3.Liquid-gas phase reaction
Fluorination is a chemical reaction involving the substitution of hydrogens to fluorine in chemical compounds. The fluorination is anextremely exothermic reaction, and the heat released during the reaction can destroyed the structures of chemical molecular. Therefore, the fluorination has advantages by using the continuous flow system compared to the batch flow system, such as temperature control, higher yield of production and lower yield of wastes.There are several researches proving the hypothesis. Jessica R et al. presented the first example of the 4-Fluoropyrazo