The Journal of Organic Chemistry
Note
(dd, J = 7.9, 1.7 Hz, 1H), 7.51 (td, J = 7.7, 1.2 Hz, 1H), 7.31 (ddd, J =
8.0, 7.4, 1.7 Hz, 1H). 19F NMR (470 MHz, CDCl3): δ 28.6 (s, 1F).
The analytical data are in agreement with those previously reported in
the literature.15
benzaldehyde (54.7 mg) as an internal standard. 19F NMR (470
MHz, CDCl3): δ 15.3 (s, 1F).
Terephtaloyl Difluoride (2r). According to a general procedure
starting with terephthalic acid (1.0 mmol, 166 mg) and using 2.2
equiv of XtalFluor-E instead of 1.1 equiv, acyl fluoride 2r was
observed in 98% 19F NMR yield using 4-(trifluoromethyl)-
benzaldehyde as an internal standard and isolated as a white solid
(91 mg, 76%) after filtration over silica using hexanes as the eluent.
Mp = 118.6−121.4 °C. 1H NMR (500 MHz, CDCl3): δ 8.22 (s, 4H).
13C{1H} NMR (101 MHz, CDCl3): δ 155.9 (d, JC−F = 346.7 Hz),
131.8 (dd, JC−F = 3.7, 1.1 Hz), 130.7 (d, JC−F = 62.6 Hz). 19F NMR
(470 MHz, CDCl3): δ 20.9 (s, 2F). FT-IR (ν/cm−1): 3109, 3063,
2955, 2918, 2849, 1809, 1416, 1404, 1232, 1034, 1007, 906. HRMS:
Under all the conditions tested for MS analysis (ESI-TOF or APPI-
TOF with or without additives), no significant ions could be detected.
5-Phenylpentanoyl Fluoride (2s). According to a general
procedure starting with 5-phenylpentanoic acid (1.0 mmol, 178
mg), acyl fluoride 2s was observed in 99% 19F NMR yield using 4-
(trifluoromethyl)benzaldehyde as an internal standard and isolated as
a transparent oil (130 mg, 72%) after filtration over silica using
pentane as the eluent. 1H NMR (500 MHz, CDCl3): δ 7.32−7.28 (m,
2H), 7.23−7.17 (m, 3H), 2.69−2.64 (m, 2H), 2.55−2.50 (m, 2H),
1.75−1.70 (m, 4H). 13C{1H} NMR (126 MHz, CDCl3): δ 163.6 (d,
4-Methoxybenzoyl Fluoride (2j). According to a general procedure
starting with 4-methoxybenzoic acid (1.0 mmol, 309 mg), acyl
fluoride 2j was observed in 99% 19F NMR yield using 2-fluoro-4-
nitrotoluene as an internal standard and isolated as a colorless oil (152
1
mg, 99%) after filtration over silica using hexanes as the eluent. H
NMR (500 MHz, CDCl3): δ 8.09−8.05 (m, 2H), 6.97−6.94 (m, 2H),
3.88 (s, 3H). 19F NMR (470 MHz, CDCl3): δ 15.9 (s, 1F). The
analytical data are in agreement with those previously reported in the
literature.7
3-Methoxybenzoyl Fluoride (2k). According to a general
procedure starting with 3-methoxybenzoic acid (1.0 mmol, 152
mg), acyl fluoride 2k was observed in quantitative 19F NMR yield
using 4-(trifluoromethyl)benzaldehyde as an internal standard and
isolated as a colorless oil (129 mg, 84%) after filtration over silica
1
using hexanes as the eluent. H NMR (500 MHz, CDCl3): δ 7.65
(ddd, J = 7.7, 1.6, 1.1 Hz, 1H), 7.54−7.52 (m, 1H), 7.45−7.40 (m,
1H), 7.24 (ddd, J = 8.3, 2.7, 1.0 Hz, 1H), 3.87 (s, 3H). 13C{1H} NMR
(126 MHz, CDCl3): δ 160.1 (d, JC−F = 1.9 Hz), 157.5 (d, JC−F = 344.7
Hz), 130.3 (d, JC−F = 1.2 Hz), 126.2 (d, JC−F = 60.7 Hz), 124.0 (d,
J
C−F = 3.4 Hz), 122.2, 115.6 (d, JC−F = 4.3 Hz), 55.7. 19F NMR (470
JC−F = 360.3 Hz), 141.7, 128.6, 128.5, 126.1, 35.5, 32.1 (d, JC−F = 50.4
MHz, CDCl3): δ 18.6 (s, 1F). FT-IR (ν/cm−1): 3011, 2962, 2945,
2916, 2849, 1805, 1601, 1489, 1431, 1292, 1271, 1205, 1176, 1020,
870. HRMS: Under all of the conditions tested for MS analysis (ESI-
TOF or APPI-TOF with or without additives), no significant ions
could be detected.
Hz), 30.5, 23.6 (d, JC−F = 1.9 Hz). 19F NMR (470 MHz, CDCl3): δ
45.5 (s, 1F). FT-IR (ν/cm−1): 3063, 3024, 2932, 2862, 1836, 1751,
1713, 1065, 1497, 1458, 1412, 1366, 1080, 864, 702. HRMS: Under
all the conditions tested for MS analysis (ESI-TOF or APPI-TOF
with or without additives), no significant ions could be detected.
Cyclohexanecarbonyl Fluoride (2t). According to a general
procedure starting with cyclohexanecarboxylic acid (1.0 mmol, 128
mg), acyl fluoride 2t was observed in 99% 19F NMR yield using 4-
(trifluoromethyl)benzaldehyde as an internal standard and isolated as
a transparent oil (87 mg, 67%) after filtration over silica using pentane
2-Bromo-5-methoxybenzoyl Fluoride (2l). According to a general
procedure, starting with 2-bromo-5-methoxybenzoic acid (1.0 mmol,
231 mg), acyl fluoride 2l was observed in 97% 19F NMR yield using 4-
(trifluoromethyl)benzaldehyde as an internal standard and isolated as
a white solid (198 mg, 85%) after filtration over silica using hexanes as
the eluent. Mp = 37.1−39.2 °C. 1H NMR (500 MHz, CDCl3): δ 7.64
(dd, J = 8.8, 1.4 Hz, 1H), 7.51 (d, J = 3.1 Hz, 1H), 7.05 (dd, J = 8.8,
3.1 Hz, 1H), 3.85 (s, 3H). 13C{1H} NMR (126 MHz, CDCl3): δ
158.8, 154.8 (d, JC−F = 345.3 Hz), 136.1 (d, JC−F = 4.0 Hz), 125.9 (d,
JC−F = 61.3 Hz), 121.9 (d, JC−F = 1.4 Hz), 118.3 (d, JC−F = 2.0 Hz),
115.0 (d, JC−F = 4.1 Hz), 55.8. 19F NMR (470 MHz, CDCl3): δ 31.3
(s, 1F). FT-IR (ν/cm−1): 2964, 2939, 2916, 2849, 1819, 1568, 1597,
1477, 1398, 1321, 1283, 1242, 1200, 1176, 1132, 1095, 1030. HRMS
(APPI-TOF), m/z: [M + NH4]+ calcd for C8H10BrFNO2, 249.9873;
found, 249.9879.
3,5-Bis(trifluoromethyl)benzoyl Fluoride (2m). According to a
general procedure starting with 3,5-bis(trifluoromethyl)benzoic acid
(1.0 mmol, 258 mg), acyl fluoride 2m was observed in 94% 19F NMR
yield using 2-fluoro-4-nitrotoluene (68.6 mg) as an internal standard.
19F NMR (470 MHz, CDCl3): δ 19.9 (s, 1F), − 63.2 (s, 6F).
4-Hydroxybenzoyl Fluoride (2n). According to a general
procedure starting with 4-hydroxybenzoic acid (1.0 mmol, 138 mg),
acyl fluoride 2n was observed in 51% 19F NMR yield using 4-
(trifluoromethyl)benzaldehyde (36.9 mg) as an internal standard. 19F
NMR (470 MHz, CDCl3): δ 15.3 (s, 1F). The analytical data are in
agreement with those previously reported in the literature.7
Isonicotinoyl Fluoride (2o). According to a general procedure
starting with isonicotinic acid (1.0 mmol, 123 mg), acyl fluoride 2o
was observed in 74% 19F NMR yield using 2-fluoro-4-nitrotoluene
(33.4 mg) as an internal standard. 19F NMR (470 MHz, CDCl3): δ
20.9 (s, 1F). The analytical data are in agreement with those
previously reported in the literature.3a
1
as the eluent. H NMR (500 MHz, CDCl3): δ 2.51 (tt, J = 10.8, 3.8
Hz, 1H), 2.02−1.95 (m, 2H), 1.82−1.74 (m, 2H), 1.65 (m, 1H),
1.59−1.49 (m, 2H), 1.38−1.23 (m, 3H). 19F NMR (470 MHz,
CDCl3): δ 36.7 (s, 1F). The analytical data are in agreement with
those previously reported in the literature.16
Tetradecanoyl Fluoride (2u). According to a general procedure
starting with tetradecanoic acid (1.0 mmol, 228 mg), acyl fluoride 2u
was observed in 97% 19F NMR yield using 4-(trifluoromethyl)-
benzaldehyde as an internal standard and isolated as a transparent oil
(202 mg, 88%) after filtration over silica using pentane as the eluent.
1H NMR (500 MHz, CDCl3): δ 2.50 (td, J = 7.4, 1.2 Hz, 2H), 1.67
(q, J = 7.4 Hz, 2H), 1.40−1.23 (m, 20H), 0.88 (t, J = 7.0 Hz, 3H).
13C{1H} NMR (126 MHz, CDCl3): δ 163.8 (d, JC−F = 360.7 Hz),
32.3 (d, JC−F = 49.4 Hz), 32.1, 29.8, 29.8, 29.8, 29.7, 29.5, 29.5, 29.2,
28.9, 24.1 (d, JC−F = 2.1 Hz), 22.8, 14.3. 19F NMR (470 MHz,
CDCl3): δ 45.4 (s, 1F). FT-IR (ν/cm−1): 2924, 2854, 1842, 1711,
1468, 1414, 1377, 1132, 1078, 862, 719. HRMS: Under all the
conditions tested for MS analysis (ESI-TOF or APPI-TOF with or
without additives), no significant ions could be detected.
2-Phenylacetyl Fluoride (2v). According to a general procedure
starting with 2-phenyl acetic acid (1.0 mmol, 136 mg), acyl fluoride
2v was observed in the quantitative 19F NMR yield using 2-fluoro-4-
nitrotoluene as an internal standard and isolated as a light-yellow oil
(80 mg, 58%) after filtration over silica using pentane as the eluent.
1H NMR (500 MHz, CDCl3): δ 7.40−7.32 (m, 3H), 7.31−7.28 (m,
2H), 3.82 (d, J = 2.4 Hz, 2H). 19F NMR (470 MHz, CDCl3): δ 44.9
(s, 1F). The analytical data are in agreement with those previously
reported in the literature.7
Thiophene-2-carbonyl Fluoride (2p). According to a general
procedure starting with 2-thiophenecarboxylic acid (1.0 mmol, 128
mg), acyl fluoride 2p was observed in 91% 19F NMR yield using 4-
(trifluoromethyl)benzaldehyde (45.0 mg) as an internal standard. 19F
NMR (470 MHz, CDCl3): δ 24.3 (s, 1F).
Furan-2-carbonyl Fluoride (2q). According to a general procedure
starting with 2-furanoic acid (1.0 mmol, 112 mg), acyl fluoride 2q was
observed in 65% 19F NMR yield using 4-(trifluoromethyl)-
2-(Naphthalen-2-yl)acetyl Fluoride (2w). According to a general
procedure starting with 2-(naphthalen-2-yl)acetic acid (1.0 mmol, 186
mg), acyl fluoride 2w was observed in 99% 19F NMR yield using 2-
fluoro-4-nitrotoluene as an internal standard and isolated as a white
solid (138 mg, 73%) after filtration over silica using pentane as the
1
eluent. H NMR (500 MHz, CDCl3): δ 7.88−7.81 (m, 3H), 7.76 (s,
1H), 7.54−7.48 (m, 2H), 7.40 (dd, J = 8.4, 1.8 Hz, 1H), 3.99 (d, J =
E
J. Org. Chem. XXXX, XXX, XXX−XXX