Novel generation ponytails in fluorous chemistry: Syntheses of primary, secondary, and tertiary (nonafluoro-tert-butyloxy)ethyl amines

(Nonafluoro-tert-butyloxy)ethyl tosylate 4 was prepared in 65% yield from nonafluoro-tert-butanol 1 using commercially available reagents. Further reaction of 4 with HNR1R2 (R1 = R2 = H, CH3; R1 = H, R2 = CH3, (CH2)3C8F17, CH2CH2OC(CF3)3) affords the appropriate (CF3)3COCH2CH2NR1R2 amines in 20–69% yields. Improved overall yields of [(CF3)3COCH2CH2]3−nNRn to 1 were obtained by the reaction of (CF3)3CONa 2 and (XCH2CH2)3−nNRn (X = Cl, n = 0, 1, 2, R = CH3; X = CH3SO2O, n = 1, R = CH3SO2) nitrogen mustards and a similar reactive β-substituted ethyl amine. The title amines are mobile colorless liquids and volatile with steam. The bulky fluorous ponytail (CF3)3CO(CH2)2 displays high acidic stability and increases fluorous character almost as much as the classical straight-chain C8F17(CH2)3 ponytail.