178
G. Bissky et al. / Journal of Fluorine Chemistry 109 92001) 173±181
MAT 8222 spectrometer under EI and FAB conditions, for
the covalent and ionic derivatives, respectively. NMR spec-
tra were recorded on a Bruker DPX-200 spectrometer
operating at 200.13 for 1H 4TMS), 188.31 for 19F 4CClF3),
50.32 MHz for 13C 4TMS), some 13C NMR spectra were
recorded on a Bruker AMX-360 spectrometer at 90.56 MHz
4TMS). Compounds 8a,b, 12a,b, 14a,b, 15b, 20, 26a-OTf
were prepared according to [26], for compound 11 see
also [24]. Cyclic voltammetry was performed using a
`home-made' potentiostat [38] with a positive feedback
Ohmic drop compensation and a Tacussel GSTP4 signal
generator. The working electrode was a glassy carbon
4Tokai Corporation) disc 43 mm diameter) and the reference
electrode a SCE. The supporting electrolyte was tetrabu-
tylammonium hexa¯uorophosphate 4NBu4PF6; Fluka pur-
iss). For puri®cation of solvents used for cyclic
voltammetry cf. [7,8].
JHH 8:3 Hz); 19F NMR d 4CD3CN À80:4 4s, CF3),
À82.2 4d, CF2, 2JPF 70:7 Hz); 31P NMR
4CD3CN 15:7 4t, 1P); HRMS calcd. for C20H20N2F2P
357.13322; found 357.132221.
d
3.4. 1-9Difluoro-trimethylsilyl-methyl)-4-dimethylamino-
pyridinium triflate 94)
Yield 53%; mp 117±1188C; 1H NMR d 4CDCl3 0:3 4s,
CH3), 3.3 4s, CH3), 7.2 4d, CH, JHH 7:8 Hz), 8.0 4d,
JHH 8:3 Hz), 19F NMR d 4CDCl3 À79:5 4s, CF3),
À92.9 4s, CF2); 13C NMR d 4CDCl3) À5.0 4CH3), 40.6
4CH3), 120.7 4q, CF3, JCF 321:0 Hz), 125.6 4t, CF2,
JCF 303:7 Hz), 108.6±157.3 4m); HRMS calcd. for
C11H19N2F2Si 245.12856; found 245.12877; anal. calcd.
for C12H19N2F5SiO3S: C 36.54, H 4.86, F 24.08; found C
36.48, H 4.79, F 24.0%.
3.1. 1-91,1-Difluoro-2-hydroxy-2-phenyl-ethyl)-4-
dimethylamino-pyridinium bromide 92)
3.5. 1-91,1-Difluoro-2-hydroxy-2-phenyl-ethyl)-3-methyl-
imidazolium triflate 925a-OTf)
To a solution of 2.62 g 47.89 mmol) of 1 and 4.18 g
439.5mmol) of benzaldehyde in 15 ml benzonitrile was
added at À208C in 1.58 g 47.89 mmol) of TDAE, stirred
at À208C for 1 h and for 1 h at ambient temperature. After
®ltrating-off TDAE2 2BrÀ, 20 ml water was added, then
the remaining water evaporated and the residue recrystal-
lized from acetonitrile. Yield of 2 1.3 g 446%), mp 2258C;
1H NMR 4CD3CN) d 3:3 4s, CH3), 4.7 4s, CH), 5.5 4s,
OH), 7.1 4s, CH), 7.4 4s, CH), 8.3 4s, CH); 19F NMR d
Yield 47%; mp 112±1138C; 1H NMR d 4CDCl3 3:9 4s,
CH3), 4.7 4s, CH), 5.5 4s, OH), 7.6 4s, CH), 7.7 4s, CH), 9.2 4s,
CH); 19F NMR d 4CDCl3) À80.5 4s, CF3), À86.9 4dd, CF2,
3
JFF 209:8, JFH 3:5 Hz), À98.3 4dd, CF2, JFF 209.8,
3JFH 14.1 Hz); 13C NMR 4&) 4CDCl3 39:3 4s, CH3),
2
72.5 4t, CH, JCF 31:9 Hz), 129.3 4t, JCF 275:3 Hz),
124.1 4s, CH), 121.9 4q, JCF 320:8 Hz), 129.5±141.9 4m);
HRMS calcd. for C12H13N2F2O 239.22316; found:
239.22738.
3
4CD3CN À91:9 4dd, JFF 202:7, JFH 3:6 Hz),
3
À101.3 4dd, JFF 202:7, JFH 3:6 Hz); 13C NMR d
3.6. 1-91,1-Difluoro-2-hydroxy-2-phenyl-ethyl)-2-phenyl-
3-methyl-imidazolium triflate 925b-OTf)
4CD3CN 41:2 4s, CH3), 73.2 4m, CH), 121.0 4t, CF2,
JCF 270:5 Hz), 108.0±157.8 4m); HRMS calcd. for
Yield 54%; mp 122±1238C; 1H NMR d 4CDCl3 3:8 4s,
CH3), 4.5 4s, CH), 5.7 4s, OH), 7.2±7.7 4m, 7H); 19F NMR d
4CDCl3 À80:4 4s, CF3), À82.3 4dd, JFF 201:8, CF2,
C15H17N2F2O 279.13089; found 279.13250; anal. calcd.
for C15H17N2F2OBr: C 50.15, H 4.77, F 10.58; found: C
50.25, C 4.85, F 10.7%.
3JFH 3:4 Hz),
À92.8
4dd,
CF2,
JFF 219:3,
3JFH 13:1 Hz); 13C NMR 4&) 4CDCl3 40:1 4s,
3.2. Typical procedure for 3, 4, 25a,b-OTf
CH3), 85.2 4t, CH, 2JCF 28:1 Hz), 135.2 4t,
1
To a solution of 2.74 g 425.3 mmol) of chlorotrimethyl-
silane and 0.84 g 42.53 mmol) of 1 in 15 ml benzonitrile
was added at À208C in 0.51 g 42.53 mmol) of TDAE,
stirred at À208C for 1 h and for 1 h at ambient tempera-
ture. After ®ltrating-off TDAE2 2BrÀ, trimethylsilyl
tri¯ate 0.42 g 42.53 mmol) was added and the solution
stirred for additional 15 min at ambient temperature. After
evaporation of the solvent under reduced pressure, the
residue was recrystallized from THF. Yield of 4 0.53 g
453%).
1JCF 289:4 Hz), 121.8 4q, JCF 320:7 Hz), 124.5±
145.1 4m); HRMS calcd. for C18H17N2F2O 315.31498;
found: 315.31453.
3.7. Tetramethylammonium 1-91,1-difluoro-2-phenyl-
ethylat)-4-dimethylamino-pyridinium triflate 95)
1
Yield 32%; mp 254±2568C; H NMR d 4CD3CN 3:1
4s, CH3), 3.2 4s, CH3), 4.7 4s, CH), 7.2 4s, CH), 7.4 4s, CH),
8.3 4s, CH); 19F NMR d 4CD3CN À80:4 4s, CF3), À93.8
4dd, JFF 200:1, 3JFH 3:0 Hz), À103.6 4dd, JFF 200:1,
3JFH 13:8 Hz); 13C NMR d 4CD3CN 40:3 4s, CH3),
56.3 4s, CH3), 120.9 4q, CF3, JCF 321:1 Hz), 125.6 4t, CF2,
JCF 303:7 Hz), 107.4±159.1 4m); anal. calcd. for
C20H28F5N3O4S: C 47.90, H 5.63, F 18.94; found: C
47.85, H 5.69, F 19.01%.
3.3. 1-9Difluoro-diphenyl-phosphanyl-methyl)-4-
dimethylamino-pyridinium triflate 93)
1
Yield 67%; mp 115±1168C; H NMR d 4CD3CN 3:2
4s, CH3), 6.8 4d, CH, JHH 8:3 Hz), 8.0 4d, CH,