Molander and Cavalcanti
JOCArticle
Dibenzo[b,d]furan-4-ol (3a). The general procedure was em-
ployed using potassium (dibenzo[b,d]furan-4-yl)trifluoroborate,
and the reaction was complete in 5 min. The desired pure
product was obtained in 97% yield (0.18 g, 0.97 mmol) as a
white solid, mp 98-100 °C. 1H NMR (500 MHz, CDCl3): δ 7.93
(d, J=7.7 Hz, 1H), 7.57 (d, J=8.3 Hz, 1H), 7.51 (d, J=7.7 Hz,
1H), 7.46 (t, J=7.8 Hz, 1H), 7.35 (t, J=7.5 Hz, 1H), 7.23 (m,
1H), 7.02 (d, J=7.9 Hz, 1H), 5.39 (s, 1H). 13C NMR (125.8
MHz, CDCl3): δ 156.1, 144.0, 141.1, 127.3, 125.7, 124.6, 123.7,
123.0, 121.0, 113.6, 112.8, 111.8. IR (neat): 3277, 1603, 1437,
1249, 744 cm-1. HRMS (ESI): m/z calcd for C12H7O2 (M - H)-
183.0446, found 183.0454.
5 min. The desired pure product was obtained in 94% yield
(0.21 g, 0.94 mmol) as a light yellow solid, mp 117-120 °C. 1H
NMR (500 MHz, CDCl3): δ 7.49-7.37 (m, 2H), 7.21 (d, J=8.9
Hz, 1H), 3.97 (s, 2H). 13C NMR (125.8 MHz, CDCl3): δ 201.5,
136.1, 133.9, 131.4, 127.9, 124.3, 119.7, 47.1. FT-IR (neat): 1711,
1017, 819 cm-1. HRMS (ESI): m/z calcd for C8H4OSBr (M - H)-
226.9166, found 226.9158.
4-Methylthiophen-2(3H)-one (3h). The general procedure was
employed using potassium (4-methylthiophen-2-yl)trifluoro-
borate, and the reaction was complete in 5 min. The desired
pure product was obtained in 89% yield (0.10 g, 0.89 mmol) as a
1
light yellow oil. H NMR (500 MHz, CDCl3): δ 6.09 (m, 1H),
Dibenzo[b,d]thiophen-4-ol (3b). The general procedure was
employed using potassium (dibenzo[b,d]thiophen-4-yl)trifluoro-
borate, and the reaction was complete in 5 min. The desired pure
product was obtained in 97% yield (0.18 g, 0.97 mmol) as a white
solid, mp 158-160 °C. 1H NMR (500 MHz, CDCl3): δ 8.13 (m,
1H), 7.89 (m, 1H), 7.78 (d, J=7.9 Hz, 1H), 7.50-7.42 (m, 2H),
3.97 (s, 2H), 2.21 (s, 3H). 13C NMR (125.8 MHz, CDCl3): δ
199.7, 167.7, 129.0, 40.8, 18.9. FT-IR (neat) 2918, 1676, 1096,
653 cm-1. HRMS (ESI): m/z calcd for C5H7OS (M þ H)þ
115.0218, found 115.0215.
Furan-2(3H)-one (3i).25 The general procedure was employed
using potassium (thiophen-3-yl)trifluoroborate, and the reac-
tion was complete in 5 min. The desired pure product was
obtained in 98% yield (0.10 g, 0.98 mmol) as a light yellow oil.
1H NMR (500 MHz, CDCl3): δ 6.77 (m, 1H), 5.55 (m, 1H), 3.14 (s,
2H). 13C NMR (125.8 MHz, CDCl3): δ 176.5, 143.8, 105.4, 32.3.
4-Hydroxybutyl Benzoate (4a).26 The general procedure was
employed using potassium (4-(benzoyloxy)butyl)trifluoro-
borate, and the reaction was complete in 2 min. The desired
pure product was obtained in 99% yield (0.19 g, 0.99 mmol) as a
colorless oil. 1H NMR (500 MHz, CDCl3): δ 8.04-8.02 (m, 2H),
7.53 (m, 1H), 7.44-7.40 (m, 2H), 4.35 (t, J=6.5 Hz, 2H), 3.70 (t,
J=6.5 Hz, 2H), 2.60, (br s, 1H), 1.88-1.83 (m, 2H), 1.74-1.69
(m, 2H). 13C NMR (125.8 MHz, CDCl3): δ 166.7, 132.8, 130.2,
129.4, 128.3, 64.8, 62.0, 29.1, 25.1.
7.34 (t, J=7.8 Hz, 1H), 6.88 (d, J=7.7 Hz, 1H), 5.35 (s, 1H). 13
C
NMR (125.8 MHz, CDCl3): δ 150.5, 139.6, 137.9, 135.9, 126.9,
126.5, 125.7, 124.4, 123.1, 122.0, 114.5, 111.7. IR (neat): 3230,
1569, 1444, 1253, 744 cm-1. HRMS (ESI): m/z calcd for
C12H7OS (M - H)- 199.0218, found 199.0222.
6-Chloropyridin-3-ol (3c). The general procedure was em-
ployed using potassium (6-chloropyridin-3-yl)trifluoroborate,
and the reaction was complete in 5 min. The desired pure
product was obtained in 91% yield (0.12 g, 0.97 mmol) as a
white solid, mp 155-157 °C. 1H NMR (500 MHz, acetone-d6): δ
9.04 (br s, 1H), 7.99 (d, J=2.9 Hz, 1H), 7.40-7.14 (m, 2H). 13
C
NMR (125.8 MHz, acetone-d6): δ 154.9, 142.5, 138.9, 127.6,
126.1. IR (neat): 3004, 1573, 1464, 1278, 1228, 826 cm-1. HRMS
(ESI): m/z calcd for C5H3NOCl (M - H)- 127.9903, found
127.9902.
6-Hydroxyhexyl Benzoate (4b).27 The general procedure was
employed using potassium (7-(benzoyloxy)hexyl)trifluoro-
borate, and the reaction was complete in 2 min. The desired
pure product was obtained in 99% yield (0.23 g, 0.99 mmol) as a
colorless oil. 1H NMR (500 MHz, CDCl3): δ 8.05-8.03 (m, 2H),
7.53 (m, 1H), 7.44-7.41 (m, 2H), 4.31 (t, J=6.5 Hz, 2H), 3.63 (t,
J=6.5 Hz, 2H), 2.38, (br s, 1H), 1.80-1.75 (m, 2H), 1.62-1.56
(m, 2H), 1.48-1.43 (m, 4H). 13C NMR (125.8 MHz, CDCl3): δ
166.6, 132.7, 130.2, 129.4, 128.2, 64.8, 62.4, 32.4, 28.5, 25.7, 25.3.
3-Bromopropan-1-ol (4c).28 The general procedure was em-
ployed using potassium (3-bromopropyl)trifluoroborate, and
the reaction was complete in 2 min. The desired pure product
was obtained in 98% yield (0.14 g, 0.98 mmol) as a colorless oil.
1H NMR (500 MHz, CDCl3): δ 3.78 (t, J=6.0 Hz, 2H), 3.54 (t,
J=6.5 Hz, 2H), 2.69 (br s, 1H), 2.11-2.07 (m, 2H). 13C NMR
(125.8 MHz, CDCl3): δ 60.1, 34.9, 30.3.
6-Fluoro-5-methylpyridin-3-ol (3d). The general procedure
was employed using potassium (6-chloropyridin-3-yl)trifluor-
oborate, and the reaction was complete in 5 min. The desired
pure product was obtained in 94% yield (0.12 g, 0.94 mmol) as a
1
white solid, mp 120-122 °C. H NMR (500 MHz, CDCl3): δ
7.69 (br s, 1H), 7.61 (s, 1H), 7.22 (m, 1H), 2.25 (s, 3H).13C NMR
(125.8 MHz, CDCl3): δ 157.1, 155.2, 151.1, 129.8 (dd, J=44.4,
9.5 Hz), 120.7 (d, J=34.1 Hz), 14.4. 19F NMR (470.8 MHz,
CDCl3): δ -83.9. IR (neat): 3048, 1471, 1232, 770 cm-1. HRMS
(ESI): m/z calcd for C6H7NOF (M þ H)þ 128.0512, found
128.0510.
Benzo[b]thiophen-2(3H)-one (3e).23 The general procedure
was employed using potassium (benzothiophen-2-yl)trifluoro-
borate, and the reaction was complete in 5 min. The desired pure
product was obtained in 99% yield (0.15 g, 0.99 mmol) as a light
yellow oil. 1H NMR (500 MHz, acetone-d6): δ 7.44 (m, 1H), 7.38
Cyclopentanol (4d).29 The general procedure was employed
using potassium cyclopentyltrifluoroborate, and the reaction
was complete in 2 min. The desired pure product was obtained in
99% yield (0.09 g, 0.99 mmol) as a colorless oil. 1H NMR (500
MHz, CDCl3): δ 4.33 (m, 1H), 1.78-1.76 (m, 4H), 1.59 (br s,
1H), 1.58-1.56 (m, 4H). 13C NMR (125.8 MHz, CDCl3): δ 74.0,
35.5, 23.2.
(d, J = 7.5 Hz, 1H), 7.33 (m, 1H), 7.25 (m, 1H), 4.09 (s, 2H). 13
C
NMR (125.8 MHz, acetone-d6): δ 203.7, 138.3, 134.7, 129.8,
127.7, 126.7, 124.5, 48.4.
Benzofuran-2(3H)-one (3f).24 The general procedure was em-
ployed using potassium (benzofuran-2-yl)trifluoroborate, and
the reaction was complete in 5 min. The desired pure product
was obtained in 97% yield (0.13 g, 0.97 mmol) as a light yellow
oil. 1H NMR (500 MHz, CDCl3): δ 7.32-7.24 (m, 2H), 7.13 (m,
1H), 7.08 (d, J=8.1 Hz, 1H), 3.71 (s, 2H). 13C NMR (125.8
MHz, CDCl3): δ 174.0, 154.6, 128.8, 124.5, 123.9, 123.0, 110.6,
32.8.
2-Methylcyclohexanol (4e).30 The general procedure was em-
ployed using potassium (2-methylcyclohexyl)trifluoroborate,
and the reaction was complete in 2 min. The desired pure
product was obtained in 96% yield (0.11 g, 0.96 mmol) as a
(25) Yanai, H.; Takahashi, A; Taguchi, T. Tetrahedron Lett. 2007, 48,
2993.
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Chem., Int. Ed. 2005, 44, 75.
(27) Saburi, H.; Tanaka, S.; Kitamura, M. Angew. Chem., Int. Ed. 2005,
44, 1730.
5-Bromobenzo[b]thiophen-2(3H)-one (3g). The general proce-
dure was employed using potassium (5-bromobenzo[b]thio-
phen-2-yl)trifluoroborate, and the reaction was complete in
(28) Shah, S. T. A.; Singh, S.; Guiry, P. J. J. Org. Chem. 2009, 74, 2179.
(29) Abraham, R. J.; Koniotou, R.; Sancassan, F. J. Chem. Soc., Perkin
Trans. 2 2002, 2025.
(23) Chen, S.; Zhao, X.; Chen, J.; Chen, J.; Kuznetsova, L.; Wong, S. S.;
Ojima, I. Bioconjugate Chem. 2010, 21, 979.
(24) Kim, M.-J.; Kim, J.-J.; Won, J.-E.; Kang, S.-E; Park, S.-E.; Jung,
K.-J.; Lee, S.-G.; Yoon, Y.-J. Bull. Korean Chem. Soc. 2008, 29, 2247.
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