T. Komata et al. / Journal of Fluorine Chemistry 128 (2007) 902–909
907
1
2
19
1.32 (3H, d, J = 7.1 Hz), 1.10 (3H, t, J = 7.1 Hz); F NMR
hydroxy-5-(trifluoromethyl)hexan-3-one (6; R = H, R = Et)
and 5,5,5-trifluoro-4-hydroxy-3-methyl-4-(trifluoromethyl)-
pentan-2-one (7) in 85% and 8% yields, respectively. The
reaction mixture was purified by distillation (75–76 8C/6.7 kPa)
+
(CDCl ): d ꢁ79.1 (6F, s); EI-MS m/z (rel. int.): 253 [M + 1]
3
+
(4), 223 [M-C H ] (12), 175 [M-C H CO-HF] (10), 125 [M-
+
2
5
+
2 5
+
C H CO-HCF ] (30), 97 (7), 69 [CF ] (12), 57 [C H CO]
+
2
5
3
3
2 5
1
2
to give 15.5 g (52% yield) of 6 (R = H, R = Et).
,6,6-Trifluoro-5-hydroxy-5-(trifluoromethyl)-3-hexanone
(1 0 0). Anal. Calcd for C H F O : C, 38.11; H, 4.00. Found:
8 10 6 2
6
C, 38.05; H, 3.84.
1
2
; 1
(
NMR (CDCl ) d 6.86 (1H, s), 2.92 (2H, s), 2.61 (2H, q,
6; R = H, R = Et): a colorless oil; bp 75–76 8C/6.7 kPa H
4.3.6. 2-(1,1,1,3,3,3-Hexafluoro-2-hydroxypropan-2-
3
1
J = 7.2 Hz), 1.11 (3H, t, J = 7.2 Hz); F NMR (CDCl ) 5–78.8
9
1
yl)cyclopentanone [6: R + R = –(CH ) –]
2
3
2 3
+
6F, s); EI-MS m/z (rel. int.): 239 [M + 1] (0.2), 209 [M-C H ]
+
(
(
(
A colorless oil: bp 81–83 8C/2.9 kPa (1.0 kPa = 7.5 Torr);
2
5
+
+
20), 181 [M-C H CO] (7.7), 69 [CF ] (16), 57 [C H CO]
+
1
H NMR (CDCl ) d 7.01 (1H, s), 2.33 (6H, m), 1.77 (1H,
19
2
5
3
2
5
3
+
1 0 0), 29 [C H ] (39). Anal. Calcd for C H F O : C, 35.31;
m); F NMR (CDCl ) d ꢁ72.5 (3F, q, J = 9.2 Hz), ꢁ78.3
2
5
7
8
6
2
3
+
(3F, q, J = 9.2 Hz); EI-MS m/z (rel. int.): 250 [M] (14),
H, 3.39. Found: C, 34.83; H, 3.09.
,5,5-Trifluoro-4-hydroxy-3-methyl-4-(trifluoromethyl)-2-
+
+
5
pentanone (7): H NMR (CDCl ) d 6.86 (1H, s), 2.92 (2H, s),
190 [M-C H -H O] (3), 163 (4), 125 [M-C H CO-HCF ]
3 6 2 2 3 3
1
+
+
(4), 83 [C H CO] (2), 55 [C H CO] (1 0 0). Anal. Calcd
4 7 2 3
3
19
2
.61 (2H, q, J = 7.2 Hz), 1.11 (3H, t, J = 7.2 Hz); F NMR
+
for C H F O : C, 38.41; H, 3.22. Found: C, 38.10; H,
8 8 6 2
(
(
[
CDCl ): d ꢁ78.8 (6F, s); EI-MS m/z (rel. int.): 223 [M-CH ]
3.15.
3
3
+
0.1), 69 [CF ] (5), 43 [CH CO] (100), 28 [CO] (1.9), 18
+
+
3
3
+
+
+
H O] (41), 17 [OH] (9), 15 [CH ] (3).
4.3.7. 2-(1,1,1,3,3,3-Hexafluoro-2-hydroxypropan-2-
1
2
3
2
Similarly, various ketones were subjected to the reaction
yl)cyclohexanone [6: R + R = –(CH ) –]
2 4
1
with HFA in the presence of concentrated sulfuric acid. Their
yields were given in Table 3. The physical properties of the
obtained 6 were shown in the following.
A colorless oil: bp 98–100 8C/2.2 kPa; H NMR (CDCl ) d
3
19
7.25 (1H, s), 3.02 (1H, m), 2.11 (8H, m); F NMR (CDCl ) d
3
ꢁ72.6 (3F, q, J = 10.2 Hz), ꢁ76.8 (3F, q, J = 10.2 Hz); EI-MS
+
+
m/z (rel. int.): 264 [M] (4), 195 [M-CF ] (6), 125 [M-
3
+
+
+
4
.3.2. 6,6,6-Trifluoro-5-hydroxy-2-methyl-5-
C H CO-HCF ] (5), 97 [C H CO] (21), 83 [C H CO] (8),
3 5 3 5 9 4 7
1
trifluoromethyl)-3-hexanone (6: R = H, R = i-Pr)
A colorless oil: bp 52–54 8C/4.0 kPa; H NMR (CDCl ) d
2
+
+
+
(
69 [CF ] (26), 55 [C H CO] (1 0 0), 41 [C H ] (28). Anal.
3 2 3 3 5
1
Calcd for C H F O : C, 40.92; H, 3.82. Found: C, 40.73;
9 10 6 2
3
7
.03 (1H, s), 2.96 (1H, s), 2.70 (1H, sep, J = 7.1 Hz), 1.17 (6H, d,
1
H, 3.68.
9
J = 7.1 Hz); F NMR (CDCl ): d ꢁ78.3 (6F, s); EI-MS m/z (rel.
3
+
int.) 253 [M + 1] 0.2, 209 [M-C H ] (18), 181 [M-C H CO]
+
+
4.4. Reduction of 5,5,5-trifluoro-4-hydroxy-4-
(trifluoromethyl)-2-pentanone (3)
3
7
3 7
+
+
4), 71 [C H CO] (100), 43 [C H ] (64). Anal. Calcd for
(
C H F O : C, 38.11; H, 4.00. Found: C, 38.27; H, 4.24.
3
7
3 7
8
10 6 2
A stirring magnet coated with tetrafluoroethylene resin was
placed in a 100 mL pressure-proof glass reactor equipped with
a pressure gauge, and a thermometer. After 20 mL of
diisopropyl ether, 20.0 g (0.089 mol) of 5,5,5-trifluoro-4-
hydroxy-4-(trifluoromethyl)pentan-2-one (3: purity 99.5%)
and 2.0 g of 5% Ru/C (water content: 50%; made by N.E.
CHEMCAT CORPORATION, Japan) were successively
introduced, the atmosphere of the reactor was replaced with
hydrogen, and then the hydrogen pressure was adjusted to
0.6 MPa. The reactor was heated at 85 8C (internal tempera-
ture) for 6 h. It was shown by GC analysis the reaction mixture
contained 99.5% 1,1,1-trifluoro-2-(trifluoromethyl)pentane-
4
.3.3. 1,1,1-Trifluoro-2-hydroxy-6-methyl-2-
1
trifluoromethyl)-4-heptanone (6: R = H, R = i-Bu)
2
(
1
A colorless oil: bp 75–78 8C/2.9 kPa; H NMR (CDCl ) d
3
6
.93 (1H, broad s), 2.90 (2H, s), 2.46 (2H, d, J = 6.6 Hz), 2.16
1
1H, sep, J = 6.6 Hz), 0.95 (6H, d, J = 6.6 Hz); F NMR
9
(
(
[
[
[
+
CDCl ):dꢁ78.7(6F, s);EI-MSm/z(rel. int.)266[M] (0.9), 251
+
M-C H CO] (7), 85 [C H CO] (72), 69 [CF ] (22), 57
+
C H CO] (100), 43 [C H ] (49), 41 [C H ] (44). Anal. Calcd
3
+
M-CH ] (9), 224 [M-C H ] (22), 209 [M-C H CO] (22), 181
+
+
3
3
6
2 5
+
+
4
9
4
9
3
+
+
2
5
3
7
3 5
for C H F O : C, 40.61; H, 4.54. Found: C, 40.78; H, 4.90.
9 12 6 2
1
2
4
.3.4. 4,4,4-Trifluoro-3-hydroxy-1-phenyl-3-
2,4-diol (13: R = H, R = Me) and 0.5% of by-products. After
the ruthenium catalyst was filtered off, the filtrate was purified
by distillation (85–87 8C/4.6 kPa) to give 16.0 g (79.5% yield)
1,1,1-trifluoro-2-(trifluoromethyl)pentane-2,4-diol (15; purity:
1
2
trifluoromethyl)-1-butanone (6: R = H, R = Ph)
(
1
A colorless viscous oil: bp 135–137 8C/2.9 kPa; H NMR
(
CDCl ) d 7.95 (2H, m), 7.68 (1H, m), 7.52 (1H, m), 7.21 (1H,
9
3
1
s), 3.46 (2H, s); F NMR (CDCl ): d ꢁ78.5 (6F, s); EI-MS m/z
99.2%,).
3
+
rel. int.): 286 [M] (1), 217 [M-CF ] (0.4), 105 [C H CO]
+
100), 77 [C H ] (46), 69 [CF ] (6), 51 (15). Anal. Calcd for
+
+
1
A colorless viscous oil: H NMR (CDCl ) d 6.62 (1H, s),
(
(
3
6
5
3
+
4.44 (1H, m), 2.79 (1H, d, J = 3.9 Hz), 2.04 (2H, m), 1.30 (3H,
1
6
5
3
9
C H F O : C, 46.17; H, 2.82. Found: C, 46.06; H, 2.19.
2
d, J = 6.1 Hz); F NMR (CDCl ) d ꢁ76.2 (3F, q, J = 10.7 Hz),
1
1
8
6
3
+
ꢁ
80.0 (3F, q, J = 10.7 Hz); EI-MS m/z (rel. int.): 227 [M + 1]
+
+
4
.3.5. 6,6,6-Trifluoro-5-hydroxy-4-methyl-5-
(0.04), 211 [M-CH ] (6), 145 (6), 139 [M-H O-CF ] (4), 123
3 2 3
1
trifluoromethyl)-3-hexanone (6: R = Me, R = Et)
2
+
+
+
(
(2.9), 91 (8), 69 [CF ] (17), 45 [C H OH] (100), 41 [C H ]
3 2 4 3 5
1
A colorless oil: bp 97–99 8C/12.0 kPa; H NMR (CDCl ): d
(7). Anal. Calcd for C H F O : C, 31.87; H, 3.57. Found: C,
6 8 6 2
3
6
.58 (1H, s), 3.17 (1H, q, J = 7.1 Hz), 2.66 (2H, q, J = 7.1 Hz),
31.91; H, 3.36.