The bromination of phosphorus oxybromide, at this time, the carbonyl group is relatively active. This mechanism is more interesting, so eliminating the nucleophilic addition makes the enol easier to synthesize than the ester itself. At this time, the positively charged oxygen is a good leaving group, similar to the α-bromination reaction of catalyzed carboxylic acid. Mainly rely on the energy of the P-O bond to increase the reaction. Of course, this step is reversible and a protonated acid halide intermediate is obtained. However, this is a bit cumbersome. The positively charged oxygen again acts as a leaving group. After cyclization, bromide ions attack the carbonyl group in turn, and the ester oxygen attacks first, so the halogenation reaction is easier, and nucleophilic addition and cyclization reactions are prone to occur. This acid halide is similar to the brominated acid halide of a carboxylic acid. Through nucleophilic substitution, a ring-opened halo acyl intermediate is obtained, and the position of the oxygen is close to the carbonyl group, which results in a nucleophilic addition reaction. After the enol is halogenated, there is no need to eliminate bromine. The previously generated bromide ions attack the phosphorus to obtain the halogenated product.
Analyzing the current phosphorus oxybromide industrial chain, my country's various industries are in strong demand and the industrial chain structure is complete, and the life cycle of related industries is analyzed. At present, my country's related industries are in the industry growth period, the downstream demand of the industry continues to grow, the number of enterprises in the industry is still on the rise, the market competition is temporarily flat, and the market concentration needs to be further increased. Analysis of the Increasing Capacity of the Tribromophosphate Industry With the growth of downstream demand of the tribromophosphate industry and the expansion of the market scale, the development capacity of the industry has maintained steady growth, and the average gross profit margin of the market is relatively good. It is expected that the industry development capacity will continue to increase in the future. Data source of the average gross profit margin trend of the brominated phosphoryl industry from 2013 to 2021: "Market Analysis and Investment Prospects Research Report on China's Brominated Phosphoryl Industry in 2021-2026" based on the relevant overview of China's brominated phosphoryl industry and the brominated phosphoryl industry Business environment, analysis of the status quo of the brominated phosphoryl industry, the supply and demand status of the brominated phosphoryl industry, the import and export status of the brominated phosphoryl industry, the competitive landscape of the brominated phosphoryl industry, and the analysis of the key points of my country's phosphorus bromide industry The business status of the enterprise and the development prospects and investment of my country's phosphorus bromide industry are analyzed. This report is a rare product for enterprises in the brominated phosphoryl production industry, scientific research institutions and other units to accurately understand the current development trend of the brominated phosphoryl industry and grasp the corporate positioning and development direction. Main research methods: systematic analysis, comparative analysis, concrete and abstract analysis, comprehensive analysis, induction and deduction, qualitative analysis, quantitative analysis, etc.