Regiospecific Synthesis of Mono-Or Diacetylated Polyethylenepol Yamine Derivatives

Phenyl esters, preferred reagents for mono-acylation of polyamines in the presence of water

“…At room temperature using the general procedure, 12 was acylated to give 13 in 56% isolated yield (entry 7). The cyclic diamine piperazine (14), which was recently mono-acylated with the more expensive ionic immobilization approach, 9 was also shown to be a good substrate for our simple and inexpensive procedure. By simply mixing 14 with 2 and suitable amount of water, the mono-acylated product 15 was obtained in 39% yield at room temperature and in 69% yield at 55°C (entries 8 and 9).…”