Overview[1]
The organophosphorus compound triethyl phosphoryl acetate is an important chemical substance that exhibits many excellent properties and is widely used in agriculture, medicine, industry, etc. The construction of phosphorus-carbon bonds through the Arbuzov reaction is an effective way to prepare compounds such as hydrocarbyl phosphonates, phosphinates, and phosphine oxides. The Arbuzov reaction was first discovered by Michaelis in 1898 and later developed by Arbuzov. It mainly uses halogenated hydrocarbons and phosphate esters as substrates to prepare hydrocarbyl phosphates. The difficulty of performing the Arbuzov reaction on halogenated hydrocarbons depends on two points: 1. It is the degree of polarization of the carbon-halogen bond. The stronger the polarity, the easier it is to proceed, so RI>RBr>RCl; dichrome carbon black is a steric obstacle to the hydrocarbon group. The greater the obstacle, the more difficult it is to proceed. Generally, it is difficult for aryl halides to undergo Arbuzov reaction. Some chlorinated hydrocarbons have low activity, limited reaction temperature of the system, and long reaction time, which greatly limits the application of this reaction in organic synthesis.
Preparation[1]
The preparation of triethyl phosphoryl acetate is as follows: heat a dry and clean 500mL coil to 170°C, take 1000g (0.7eq.8.16mol) of compound 1 (boiling point under standard atmospheric pressure 142~145°C) and place it In the mixing bottle A, add 0g cupric antioxidant benzene to dilute, take 1937g (1.0eq.11.66mol) of triethyl phosphite (boiling point under standard atmospheric pressure 156.6°C) and place it in the mixing bottle B, add 3063g toluene Dilute and start pumping after the coil temperature stabilizes. Pump A (toluene solution of triethyl phosphoryl acetate): 16.7g/min, pump B (toluene solution of triethyl phosphite): 16.7g/min. The residence time is 15 minutes, and the reaction pressure is 0.5~2.0Mpa. The discharge port is directly connected to the thin film evaporation device, the pressure is controlled to 4~10×10Pa, and the temperature is 105~115°C. Finally, 1701g of the product triethyl phosphorylacetate (boiling point 129~131°C 800Pa) is obtained, with a yield of 93 %.
