Acylation Reagents
Acylation reagents offer the same types of advantages available from silylation reagents: creating less polar, more volatile derivatives. However, in comparison to silylating reagents, the acylating reagents can more readily target highly polar multi-functional compounds, such as carbohydrates and amino acids. In addition, acylating reagents offer the distinct advantage of introducing electron-capturing groups, thus enhancing detectability during analysis.
Generally, these reagents are available as acid anhydrides, acyl derivatives, or acyl halides. The acyl halides and acyl derivatives are highly reactive and may be suited for use where issues of steric hindrance may be a factor. Acid anhydrides are available in a number of fluorinated configurations, which improve detection. These fluorinated anhydride derivatives are used primarily for Electron Capture Detection (ECD), but can also be used for Flame Ionization Detection (FID). Fluorinated anhydrides are often used in derivatizing samples to confirm drugs of abuse. Despite the special utility of these reagents, their acidic nature requires that any excess or byproducts be removed prior to analysis to prevent deterioration of the column.
Fluorinated Anhydrides: HFBA/PFPA/TFAA
Heptafluorobutyric Anhydride/Pentafluoropropionic
Anhydride/Trifluoroacetic Anhydride
CAS 10416-59-8
- Most commonly used for ECD
- React with alcohols, amines and phenols
- Bases such as triethylamine and trimethylamine can be added to promote reactivity
- Frequently used for drugs of abuse confirmation
- HFBA derivatives are the most sensitive to ECD
- PFPA derivatives require the lowest analysis temperatures
- TFAA is the most reactive and volatile of the anhydrides
HFBI
Heptafluorobutyrylimidazole
- Readily forms derivatives with phenols, alcohols and amines suitable for ECD
- Reactions are fast and mild
- Imidazole is not acidic, so no decomposition or corrosion occurs on columns
MBTFA
N-Methyl-N-bis(trifluoroacetamide)
- Reacts rapidly under mild conditions with primary and secondary amines
- Reacts more slowly with alcohols, phenols, and thiols
- Works well in the analysis of sugars
PFPOH
2,2,3,3,3-Pentafluoropropanol
- Used in combination with PFPA to make derivatives of the most common functional groups, especially polyfunctional bio-organic compounds
- Formed derivatives are highly suitable for ECD.
| Product | Size | Regis
Product # | U.S. Price |
| PFPOH |
| PFPOH | 5 gram | 270815 | $35.00 |  |
| PFPOH | 25 gram | 270816 | $95.00 | |
| MBTFA |
| MBTFA | 5 gram | 270091 | $43.00 | |
| MBTFA | 10x1 gram | 270092 | $90.00 | |
| MBTFA | 100 gram | 270093 | $525.00 | |
| MBTFA | 25 gram | 270095 | $175.00 | |
| HFBI |
| HFBI | 5x1 gram | 270611 | $105.00 | |
| HFBI | 5 gram | 270612 | $86.00 | |
| Fluorinated Anhydrides: HFBA/PFPA/TFAA |
| HFBA | 10x1 gram | 270851 | $75.00 | |
| HFBA | 25 gram | 270853 | $100.00 | |
| PFPA | 10x1 gram | 640110 | $95.00 | |
| PFPA | 25 gram | 640113 | $95.00 | |
| PFPA | 100 gram | 640114 | $275.00 | |
| TFAA | 10x1 gram | 270841 | $65.00 | |
| TFAA | 25 gram | 270843 | $30.00 | |