preparation of Dess Martin reagent

recently made about 50 g of it.
here is the detail.

1. oxone 2 eq. and 2-iodobenzylacid? 1 eq. mixed together with deionized water.
stirred at 70-73C for about 4 hr. during the stirring, the insoluable iodoacid will get into the water solution. Finally a nearly clear solution will be seen with some precipitation on the bottom. good stirring is necessary.

2. cool the temp down to 0-5C for 2hr, filter out the white precipitation. wash with acetone.
The ibx is potencially explosive, it is stable at rt and should be dried at rt and 1 atm.

3. pour in Ac2O and catalytic amount of psOH-H2O solid. heated to 80C for 3 hr, a clear solution resulted. cooled it down to 0-5 C, then liquid filtered. washed with ether.
also explosive, dried in vacuo briefly.
stored in freezer.