Method of purifying phosphorus compound and method of reusing the same

A method of purifying a phosphorus compound, comprising the steps of:

• obtaining a mixture of a phosphorus compound represented by the following general formula (1):
• wherein, in general formula (1), each of R1 and R2 independently represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aryloxy group;
• wherein R1 and R2 may be bonded with each other to form a cyclic structure, an alkenyl phosphorus compound represented by the following general formula (2):
• wherein, in general formula (2), the definitions of R1 and R2 are the same as those of R1 and R2 in the general formula (1) and a transition metal complex;
• and
• subjecting the mixture to distillation after adding a Lewis acid to the mixture, to obtain a first distillate containing the phosphorus compound represented by the general formula (1).