HFBA - Heptafluorobutyric acid anhydride

Acylation

In principle three classes of compounds can be used for acylation:- acyl halides, anhydrides and bisacylamides

Acyl Halides: are reactive, forming hydrohalic acids as by-products. Excess reagent and acid have to be removed or trapped by a suitable base (e.g. pyridine).

Anydrides: are also very reactive, forming as by-products the corresponding acids. Excess reagent and the acid formed have to be removed.

Bisacylamides: (MBTFA, MBHFBA) are very reactive and form as by-products the corresponding neutral acylamides. Reagent and by-product can easily be removed due to their high volatility. Because of the neutral conditions and the favourable chromatographic properties, removal of the bisacylamide is often unnecessary. Thus sample preparation is much more convenient.