Ethyl pentafluoropropionate

Similar effectively uncoupled signals are observed for the ester, ethyl pentafluoropropionate (Scheme 6.8), which exhibits singlets at -123 and -84 ppm. 

The higher homologue of fluoral, pentafluoropropionaldehyde, prepared by reduction of ethyl pentafluoropropionate, is a precursor of diethyl tetrafluoroketene dithioacetal, which is a versatile building block for the synthesis of trifluoromethyl-substimted functional compounds, such as trifluoromethyl lactones, lactams, and heterocyclics, as exemplified in the Figure 2.53. ... 

C5H5F502 ethyl pentafluoropropionate 426-65-3 25.00 1.2990 1 4524 C5H6N203 ethyl cyanoglyoxylate-2-oxime 3849-21-6 25.00 1.3434 2... 

Morphine (1 ng-1 yg) is solved in 50 yl dry ethyl acetate and 100 yl pentafluoropropionic anhydride is added. The tightly stoppered tube is placed in an oven at 60°C for 30 minutes. Excess of reagent is removed by a gentle stream of dry nitrogen and the residue dissolved in 50 yl dry ethyl acetate. Of this solution 1-2 yl is injected for oas chromatonraphic analysis19. 

Sample preparation Mix 500 mg homogenized kidney with 2 g 40 ji.m Bondesil preparative-grade end-capped cyanopropyl bulk packing material (Anal3rtichem), blend with mortar and pestle for 2 min. (For a higher degree of purification, use 3 g Bondesil CN and blend for 3 min.) Place in a chromatography column, wash with 3 mL hexane, wash with 5 mL ethyl acetate, wash with 5 mL MeOH, wash with 5 mL MeOH water 50 50, elute with 1 mL water and then with 8 mL 100 mM formic acid, filter (0.45 p.m) a 4.5 mL aliquot of the eluate. Concentrate 4 mL of the filtrate to 75 p,L under reduced pressure, add 7.5 xL 10% pentafluoropropionic acid in water, vortex, filter (0.20 p.m), inject a 22 p,L aliquot of the filtrate. 

Extraction Derivatization SFE Oven temperature Static extraction Dynamic extraction Extract isolation 20 mg ludr powder, treated with 20 pL ethyl acetate in the extraction cartridge (volume 150 jL) 60 C 15 min, 200—300 bar 5 min, 200—300 bar Transfer of the eluate to a sample botde with about 1 mL ethyl acetate. With pentafluoropropionic anhydride (PFPA). 

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