- 路 Microwave
- 路 Atmospheric Pressure Microwave 路 Pressure Microwave 路 Parallel Microwave
- 路 Ultrasonic 路Low Temperature Ultrasound
- 路 Ultraviolet Light
- 路 Microwave Heating 路 Atmospheric Pressure Synthesis 路 Atmospheric Pressure Catalysis 路 Atmospheric Pressure Extraction
- 路 Sample Preparation 路 Microwave Digestion
- 路 Soil Digestion 路 High Pressure Synthesis
- 路 Solid Phase Synthesis
- 路 Organic Synthesis
- 路 Ionic Liquid Synthesis
- 路 Degradation Of Natural Organic Matter
- 路 Natural Product Extraction / Purification
300UL Synthesis of methylthiomethyllithium by microwave ultraviolet light combined catalysis
>This research by the Institute of Physical Organic and Medicinal Chemistry of Capital Normal University, the paper discusses the synthesis of methylthiomethyl lithium by microwave ultraviolet light, and published in the important journal "Research Progress in
In this paper, methylthiomethyllithium was efficiently synthesized by microwave and ultraviolet light combination catalysis, and it was reacted with N-phenethylpiperidone to obtain the corresponding N-phenethyl-4-methylthiomethylpiperidine. alcohol. In the process of synthesizing methylthiomethyllithium, the relationship between time and yield of microwave and ultraviolet irradiation was designed, and the optimal catalytic reaction time was determined.
By using microwave and ultraviolet light irradiation method, when methylthiomethyllithium compound is prepared from dimethyl sulfide, tetramethylethylenediamine is not used, which can not only obtain a high yield but also greatly shorten the reaction time. Experiments show that 2 hours is the best reaction time: the reaction is almost complete and there are almost no by-products. In less than 2 hours, the reaction was incomplete and an excess of 2 hours produced unknown by-products. Dimethyl sulfide is a very weak acid and is very stable under normal conditions. In order to promote the S-H bond rupture, special energy is required. Microwaves and ultraviolet light can increase their energy inside the molecule. The energy of microwave and ultraviolet light increases the fracture tendency of C-Li bond on the one hand, and increases the cleavage of S-H bond in dimethyl sulfide on the other hand, thereby accelerating the reaction process. Experiments show that the ultraviolet light energy is the most important factor in the preparation of methylthiomethyllithium.
XH-300UL computer microwave ultrasonic ultraviolet light combined catalytic synthesis instrument (Beijing Xiangyu Technology Development Co., Ltd.), set reaction temperature 45 ° C, microwave power 400 w, ultraviolet light (UV-365, intensity 152 & micro; w / cm 2).