Page 255 - Applied Pharmacognosy

Disadv.
*the by-product , TMS-acetamide Interference
*form silicon dioxide ( FID )

4-Bis trimethyl silyl trifluoro acetamide (BSTFA)
*the by-product , trifluoro acetamide (little interference).
*form silicon triflouride.

2- Acylation

For OH, NH2, SH groups

Acylation derivatives are esters, thioesters, amides
Difficult to prepare.
Acylating reagents:
• fluorinated acid anhydrides (commonly used)
•fluoro acyl imidazole
•Acyl halides

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