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Silylation reagents
MSTFA · MSHFBA · MBDSTFA

 
Features


N-methyl-N-trimethylsilyl-trifluoroacetamide
m.w. 199.1, Bp 70 °C (75 mm Hg), density d20°/4° = 1.11
MSTFA:
R' = CF3, R" = CH3
  the most volatile trimethylsilyl amide available
very strong TMS donor which does not cause any noticeable FID fouling even after long-time measuring series
The already good solution characteristics can be improved by addition of submolar quantities of protic solvents (e. g. TFA for extremely polar compounds such as hydrochlorides) or pyridine (e. g. for carbohydrates).
recommended application: carboxylic acids, hydroxy and ketocarboxylic acids, amino acids, amines, alcohols, polyalcohols, sugars, mercaptans and similar compounds with active hydrogen atoms. Even amine hydrochlorides can be silylated directly.
advantages: complete reaction with high reaction rates, even without a catalyst (1–2  % TMCS or TSIM)
the by-product of the reaction (N-methyltrifluoroacetamide) features high volatility and short retention time
For a working protocol click here.

   
N-methyl-N-trimethylsilyl-heptafluorobutyramide
m.w. 299.1, Bp 148 °C (760 mm Hg)
MSHFBA:
R' = C3F7, R" = CH3
  similar to MSTFA in reactivity and chromatography
recommended application: carboxylic acids, alcohols, phenols, primary and secondary amines and amino acids
used either alone or in combination with a catalyst (TMCS, TSIM) or another silylation reagent with or without solvent
the by-product N-methylheptafluorobutyric amide has a lower retention time than the silylating reagent 
especially useful for flame ionisation detection due to the large ratio of fluorine to silicon of 7 : 1, since degradation of the excess of MSHFBA does not produce SiO2 but volatile, non-corrosive silicon compounds
For a working protocol click here.

   
N-methyl-N-tert-butyldimethylsilyl-trifluoroacetamide
m.w. 241.3, Bp 168 – 170 °C (760 mm Hg), density d20°/4° = 1.121
MBDSTFA:
R' = CF3, R" = C4H9
  silylation reagent which donates a tert-butyldimethylsilyl group (TBDMS) for derivatising active hydrogen atoms in hydroxyl, carboxyl and thiol groups as well as primary and secondary amines
fast reactions (typically 5 – 20 min) with high yields (> 96%)
by-products are neutral and volatile
TBDMS ethers are 104 times more stable than the corresponding TMS ethers; chromatographic retention times are longer due to the large protecting group, which may improve some separations;
because of the high molecular ion concentration at M+-57 useful for GC-MS applications
For a working protocol click here.


Ordering information

Packing unit
MSHFBA
MSTFA
MBDSTFA
10 x 1 ml
    701440.101
20 x 1 ml
701260.201
701270.201 701440.201
1 x 10 ml
701260.110 701270.110  
5 x 10 ml
701260.510 701270.510  
1 x 100 ml
701260.1100 701270.1100  
6 x 50 ml

701270.650  
6 x 100 ml
701260.6100 701270.6100  
12 x 100 ml
  701270.12100  
Due to their purpose, derivatisation reagents are very reactive substances. For this reason they should be stored cool and protected from moisture. Our derivatisation reagents are supplied in vials with crimp caps for easy access with a syringe. Vials with pierced sealing disks have limited stability and should be used soon.


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