Acetic Acid → 2-Oxo-2-ethoxy-3,3,5-trimethyl-5-diethylphosphono-1,2-oxaphospholane

Participants

Reaction Conditions

Reaction Steps

10 ml of a mixture of 70.8 g of 4-methyl-4-(diethylphosphono)-pentan-2-one (prepared from mesityl oxide and diethyl phosphite) and 82.8 g of diethyl phosphite were dissolved in 100 ml of toluene, and the solution was heated to 80° C. A catalytic amount of sodium was added and a vigorous exothermic reaction commenced. The reaction temperature was held between 80° C. and 90° C. by alternately adding the previously prepared mixture and small pieces of sodium. Altogether 1.65 g of sodium was used as catalyst. The reaction took 20 minutes. The reaction mixture was subsequently stirred at 80°-90° C. for 30 minutes with heating, then cooled and neutralized with 4.5 g of glacial acetic acid. This reaction mixture was distilled to yield 2-oxo-2-ethoxy-3,3,5-trimethyl-5-diethylphosphono-1,2-oxaphospholane with a boiling point of 156°-161° C./1.1 mm. This substance is identical to the oxaphospholane manufactured according to Example 4.

Provenance & Evidence