V-Trifluoroacetyl derivatives

A sensitive method for primary amines is shown in reaction 2, leading to the corresponding 7V-benzenesulfonyl-/V-trifluoroacetyl derivatives. These can be determined by GC-ECD using SE-30 columns LOD 1-5 pg, which is about 200 times more sensitive than GC-FID. The method was applied for determination of phenethylamine (33) in urine110. This analysis was performed also by LLE into n-pentane, derivatization to the benzenesulfonamide and GC-FPD using a capillary column recoveries of aliphatic primary amines in urine were 91-107%, RSD 0.2-4.5%111,112. Amines in environmental waters and sediments were determined after LLE with dichloromethane, derivatization with benzenesulfonyl chloride and GC-SIM-MS LOD 0.02-2 pg/L of water and 0.5-50 ng/g of sediment113. 

In an alternative route employing fewer overall steps, Borbas and Lipt k119 synthesized the trisaccharide hapten as a 4-aminophenyl glycoside protected as the (V-trifluoroacetyl derivative 13 for potential conjugation to protein.108 Ethyl 1-thio-a-L-rhamnopyranoside as the 2,3-O-diphenylmethylene acetal 23 was the precursor for both rhamnosyl residues. Condensation of 23 with glycosyl bromide 24 with silver triflate as promoter, followed by O-deacetylation and O-benzyliden-... 

Reagent used to prepare V-trifluoroacetyl derivs. of amino acids etc. Bp 148-149°. 

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