名称:
环状次膦酸盐酸水解的研究:1-烷氧基-3-膦1-氧化物、1-乙氧基-3-甲基膦1-氧化物和1-乙氧基-3-甲基-1,2,3,4,5 ,6-六氢膦1-氧化物
摘要:
AbstractThe hydrochloric acid‐catalyzed hydrolysis of phosphinates was studied on 1‐alkoxy‐3‐phospholene 1‐oxides, 1‐ethoxy‐3‐methylphospholane 1‐oxide, and 1‐ethoxy‐3‐methyl‐1,2,3,4,5,6‐hexahydrophosphinine 1‐oxide as the model compounds. Under the conditions applied, the isomerization of the 3‐phospholene moiety to the 2‐phospholene ring also occurred leading to mixtures of the corresponding 1‐hydroxy‐3‐phospholene oxide and 1‐hydroxy‐2‐phospholene oxide. According to our optimized method, using 3 equivalents (0.5 mL) of concentrated hydrochloric acid in 1 mL of water per ca. 2 mmol of the substrate at reflux, the completion required 3‐10 hour. The hydrolyses were characterized by pseudo‐first‐order rate constants and the isomerizations by rate constants. The application of p‐toluenesulfonic acid under microwave irradiation at 140°C in the hydrolysis of 1‐alkoxy‐3‐methyl‐3‐phospholene oxides associated with reaction times of 1‐3 hour. The reactivity order of the 5‐ and 6‐ring phosphinates in hydrolysis was set up.