Help DPPA is reacted with a carboxylic acid, and the BOC protecting amine compound is re-formed by CURTIUS.

Tert-butanol is solvent, 1.1 equivalent DPPA, 90 degrees seem to remember such an operation

Is your DPPA a little less?The literature molar ratio is 1: 1, you can add more, to make sure you first raw into an acid nitrogen, the raw material reaction is completely or mostly no heating.
When you rearrange, you can try two ways: one is heating for 1 to 2 hours, directly add t-butanol, temperature you can refer to the way upstairs;, Then heat together.

http://yunpan.cn/cje4xjrhnz729 (extraction code: b14f)

This reaction should be not so difficult, the acyl is more nitrogen in the case of heating, and the isocyanate is reactive, and the isocyanate is reactive to generate BOC amine, here should pay attention to two points: First of all, no water is requiredBecause of the diameruclearity of your tert-butanol, the isocyanate is hydrolyzed into an amine, and then you don't have to do it. Six or nonted, you can happen too much.It is normal.So I suggest you take an unwater THF to do a solvent, and the pick-on plate is completely disappeared. Directly add a quantitative t-butanol into the left and sole it is about 70 degrees.Cry dry is not very safe)

I also do a similar reaction, but I use benzyl alcohol, and finally CBZ, and you are BOC, my conditions are: 90 degrees of toluene, DPPA, TEA, first 90 degrees, after 2 h, then add benzAlcohol and continue to react for 3 days.After purification, hydrocarnate CBZ is added.

Blessing