The process 11, wherein {TAIL ~ the solvent} of each reaction step is a mixture of {HEAD ~ tert} butyl alcohol and an inert solvent other than the tert butyl alcohol, and the other inert solvent is used in an amount of 0.1 part by volume or less, based on 1 part by volume of the tert butyl alcohol 
The process 11 , wherein { TAIL ~ the solvent } of each reaction step is a mixture of { HEAD ~ tert } butyl alcohol and an inert solvent other than the tert butyl alcohol , and the other inert solvent is used in an amount of 0.1 part by volume or less , based on 1 part by volume of the tert butyl alcohol
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH