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6-Chloro-2-phenyl-4H-chromen-4-one (4g).23 Isolated yield:
43% (colourless solid, 66 mg, eluent: petroleum ether/EtOAc
3 : 1) m.p. 187 ꢀC; 1H NMR (500 MHz, CDCl3) d 8.17 (d, J ¼
2.6 Hz, 1H), 7.90 (dd, J ¼ 8.0, 1.4 Hz, 2H), 7.62 (dd, J ¼ 8.9, 2.6
Hz, 1H), 7.57–7.48 (m, 4H), 6.81 (s, 1H); 13C NMR (125 MHz,
CDCl3) d 177.2, 163.8, 154.7, 134.0, 132.0, 131.6, 131.3, 129.2,
126.4, 125.3, 125.1, 119.9, 107.6; HRMS (ESI) m/z ¼ 257.0364
calcd for C15H10ClO2 [M + H]+, found: 257.0365.
Hz, 1H), 8.11 (d, J ¼ 7.9 Hz, 1H), 7.91–7.87 (m, 1H), 7.68 (d, J ¼
8.1 Hz, 1H), 7.53–7.47 (m, 2H), 7.33 (d, J ¼ 8.1 Hz, 1H), 2.52 (s,
3H); 13C NMR (125 MHz, DMSO) d 176.2, 156.2, 156.1, 147.3,
135.8, 126.4, 126.3, 126.3, 124.8, 121.7, 119.5, 118.6, 118.3, 21.9;
HRMS (ESI) m/z ¼ 233.0573 calcd for C14H10NaO2 [M + Na]+,
found: 233.0569.
Chroman-4-one (4a).17 Isolated yield: 87% (colourless solid,
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1.29 g, eluent: petroleum ether/EtOAc 5 : 1) m.p. 38–39 C; H
NMR (500 MHz, CDCl3) d 7.89 (dd, J ¼ 7.5, 1.7 Hz, 1H), 7.46 (m,
1H), 7.01 (t, J ¼ 7.5 Hz, 1H), 6.96 (d, J ¼ 8.4 Hz, 1H), 4.54–4.51
(m, 2H), 2.82–2.79 (m, 2H); 13C NMR (125 MHz, CDCl3) d 191.8,
162.0, 136.0, 127.3, 121.5, 121.5, 118.0, 67.1, 37.9; HRMS (ESI)
m/z ¼ 149.0597 calcd for C9H9O2 [M + H]+, found: 149.0596.
6-Methylchroman-4-one (4b).18 Isolated yield: 77% (colour-
less solid, 190 mg, eluent: petroleum ether/EtOAc 7 : 1) m.p. 32–
33 ꢀC; 1H NMR (500 MHz, CDCl3) d 7.69 (d, J ¼ 2.0 Hz, 1H), 7.28
(dd, J ¼ 8.4, 2.0 Hz, 1H), 6.87 (d, J ¼ 8.4 Hz, 1H), 4.51–4.49 (m,
2H), 2.80–2.77 (m, 2H), 2.30 (s, 3H); 13C NMR (125 MHz, CDCl3)
d 192.1, 160.1, 137.2, 131.0, 126.9, 121.2, 117.8, 67.2, 38.0, 20.5;
HRMS (ESI) m/z ¼ 163.0597 calcd for C10H11O2 [M + H]+, found:
163.0596.
Benzyl 4-oxo-4H-chromene-2-carboxylate (4h).24 Isolated
yield: 84% (colourless solid, 94 mg, eluent: petroleum ether/
EtOAc 1 : 2) m.p. 106–107 ꢀC; 1H NMR (500 MHz, CDCl3) d
8.19 (dd, J ¼ 8.0, 1.5 Hz, 1H), 7.77–7.70 (m, 1H), 7.61 (d, J ¼ 8.5
Hz, 1H), 7.41 (m, 6H), 7.14 (s, 1H), 5.43 (s, 2H); 13C NMR (125
MHz, CDCl3) d 178.5, 160.5, 156.2, 152.2, 134.89, 134.6, 129.1,
129.0, 128.7, 126.1, 125.9, 124.7, 119.0, 115.2, 68.6; HRMS (ESI)
m/z ¼ 281.0808 calcd for C17H13O4 [M + H]+, found: 281.0806.
4H-Chromen-4-one (4i).25 Isolated yield: 37% (colourless
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solid, 137 mg, eluent: petroleum ether/EtOAc 1 : 1) m.p. 57 C;
1H NMR (500 MHz, CDCl3) d 8.20 (dd, J ¼ 8.0, 1.4 Hz, 1H), 7.84
(d, J ¼ 6.0 Hz, 1H), 7.70–7.62 (m, 1H), 7.44 (d, J ¼ 8.4 Hz, 1H),
7.39 (t, J ¼ 8.0 Hz, 1H), 6.33 (d, J ¼ 6.0 Hz, 1H); 13C NMR (125
MHz, CDCl3) d 177.6, 156.7, 155.4, 133.8, 126.0, 125.3, 125.1,
118.3, 113.1; HRMS (ESI) m/z ¼ 147.0441 calcd for C9H7O2 [M +
H]+, found: 147.0440.
2-Phenyl-4H-chromen-4-one (4c).19 Isolated yield: 83%
(colourless solid, 183 mg, eluent: petroleum ether/EtOAc 1 : 1)
m.p. 98 ꢀC; 1H NMR (500 MHz, CDCl3) d 8.24 (dd, J ¼ 8.4, 1.5 Hz,
1H), 7.93 (dd, J ¼ 7.5, 2.0 Hz, 2H), 7.74–7.67 (m, 1H), 7.57 (d, J ¼
7-Methoxy-4H-chromen-4-one (4j).26 Isolated yield: 48%
(colourless solid, 119 mg, eluent: petroleum ether/EtOAc 1 : 4)
8.4 Hz, 1H), 7.54 (m, 3H), 7.42 (t, J ¼ 7.5 Hz, 1H), 6.83 (s, 1H); 13
C
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NMR (125 MHz, CDCl3) d 178.6, 163.6, 156.5, 133.9, 132.0, 131.7,
129.2, 126.5, 125.9, 125.4, 124.2, 118.2, 107.8; HRMS (ESI) m/z ¼
223.0754 calcd for C15H11O2 [M + H]+, found: 223.0753.
6-Methoxy-2-phenyl-4H-chromen-4-one (4d).20 Isolated yield:
75% (colourless solid, 220 mg, eluent: petroleum ether/EtOAc
m.p. 105–106 C; H NMR (500 MHz, CDCl3) d 8.06 (d, J ¼ 8.9
Hz, 1H), 7.74 (d, J ¼ 6.0 Hz, 1H), 6.92 (dd, J ¼ 8.9, 2.4 Hz, 1H),
6.79 (d, J ¼ 2.4 Hz, 1H), 6.23 (d, J ¼ 6.0 Hz, 1H), 3.86 (s, 3H); 13
C
NMR (125 MHz, CDCl3) d 177.0, 164.2, 158.3, 154.9, 127.2, 118.8,
114.5, 113.0, 100.5, 55.8; HRMS (ESI) m/z ¼ 177.0546 calcd for
1
10H9O3 [M + H]+, found: 177.0545.
2-(Hydroxymethyl)benzaldehyde (I and II).27 Colorless liquid;
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6 : 1) m.p. 192–193 C; H NMR (500 MHz, CDCl3) d 7.93 (dd,
J ¼ 7.4, 2.2 Hz, 2H), 7.61 (d, J ¼ 3.1 Hz, 1H), 7.55–7.52 (m, 3H),
7.51 (s, 1H), 7.30 (dd, J ¼ 9.1, 3.1 Hz, 1H), 6.83 (s, 1H), 3.92 (s,
3H); 13C NMR (125 MHz, CDCl3) d 178.5, 163.4, 157.2, 151.3,
132.2, 131.6, 129.2, 126.4, 124.8, 124.0, 119.7, 107.1, 105.1, 56.1;
HRMS (ESI) m/z ¼ 253.0859 calcd for C16H13O3 [M + H]+, found:
253.0860.
C
product was isolated as a mixture of the ring-closed hemiacetal
and the free aldehyde: 1H NMR (500 MHz, CDCl3) for (I) d 4.78
(s, 2H), 7.80 (d, J ¼ 8.4 Hz, 1H), 10.02 (s, 1H); for (II) d 4.95 (d, J ¼
12.7 Hz, 1H), 5.18 (d, J ¼ 12.7 Hz, 1H), 6.42 (d, J ¼ 1.7 Hz, 1H).
5,7-Dimethoxy-2-phenyl-4H-chromen-4-one (4e).21 Isolated
yield: 57% (colourless solid, 144 mg, eluent: petroleum ether/
EtOAc 1 : 2) m.p. 145–146 ꢀC; 1H NMR (500 MHz, CDCl3) d
7.92–7.85 (m, 2H), 7.54–7.46 (m, 3H), 6.76 (s, 1H), 6.59 (d, J ¼ 2.2
Hz, 1H), 6.39 (d, J ¼ 2.2 Hz, 1H), 3.96 (s, 3H), 3.92 (s, 3H); 13C
NMR (125 MHz, CDCl3) d 177.7, 164.3, 161.2, 160.9, 160.1, 131.8,
131.3, 129.1, 126.1, 109.5, 109.2, 96.4, 93.1, 56.6, 55.9; HRMS
(ESI) m/z ¼ 283.0965 calcd for C17H15O4 [M + H]+, found:
283.0963.
Acknowledgements
This research was supported by the Project Funded by the
Priority Academic Program Development of Jiangsu Higher
Education Institutions (PAPD), the Program for Changjiang
Scholars and Innovative Research Team in University (IRT1193).
References
2-Phenyl-4H-benzo[h]chromen-4-one (4f).22 Isolated yield:
74% (colourless solid, 73 mg, eluent: petroleum ether/EtOAc
1 (a) K. R. Romines, G. A. Freeman, L. T. Schaller, J. R. Cowan,
S. S. Gonzales, J. H. Tidwell, C. W. Andrews, D. K. Stammers,
R. J. Hazen, R. G. Ferris, S. A. Short, J. H. Chan and
L. R. Boone, J. Med. Chem., 2006, 49, 727; (b) P. J. Masson,
D. Coup, J. Millet and N. L. Brown, J. Biol. Chem., 1995,
270, 2662; (c) A. Mitsch, P. Wissner, M. Bohm, K. Silber,
G. Klebe, I. Sattler and M. Schlitzer, Arch. Pharm., 2004,
337, 493.
1
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1 : 1) m.p. 158–159 C; H NMR (500 MHz, CDCl3) d 8.64–8.57
(m, 1H), 8.17 (d, J ¼ 8.7 Hz, 1H), 8.03 (dd, J ¼ 6.7, 3.0 Hz, 2H),
7.97–7.91 (m, 1H), 7.78 (d, J ¼ 8.7 Hz, 1H), 7.75–7.68 (m, 2H),
7.63–7.54 (m, 3H), 6.98 (s, 1H); 13C NMR (125 MHz, CDCl3) d
178.4, 163.0, 153.8, 136.3, 132.2, 131.8, 129.5, 129.4, 128.4,
127.4, 126.5, 125.6, 124.4, 122.5, 121.0, 120.4, 109.0; HRMS (ESI)
m/z ¼ 273.0910 calcd for C19H13O2 [M + H]+, found: 273.0911.
2 (a) S. E. Denmark and G. L. Beutner, Angew. Chem., Int. Ed.,
2008, 47, 1560; (b) G. A. Olah, Friedel–Cras Chemistry,
63640 | RSC Adv., 2014, 4, 63632–63641
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