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7.79 (s, 1H), 7.62 (t, J ¼ 7.4 Hz, 1H), 7.51 (t, J ¼ 7.7 Hz, 2H), 7.44 Na2SO4, ltered, and concentrated in vacuo. Aer column
(dd, J ¼ 8.4, 1.6 Hz, 1H). 13C NMR (125 MHz, CDCl3, ppm) chromatography (hexane/dichloromethane 1 : 1), 48 mg (77%)
d 170.1, 156.2, 144.1, 138.8, 134.8, 133.9, 132.2, 131.2, 129.0, of
a
yellow solid was obtained. Rf
¼
0.2 (hexane/
1
ꢀ
128.5, 126.3, 123.2, 122.8.
dichloromethane 1 : 1). Mp ¼ 187–189 C. H NMR (500 MHz,
6-Fluoro-2-phenylbenzo[4,5]thieno[3,2-d]thiazole (3ga, Scheme CDCl3, ppm) d 8.21 (dd, J ¼ 7.5, 1.5 Hz, 1H), 7.86 (dd, J ¼ 8.0,
3): following the general procedure A. 4-Fluoroacetophenone 1.0 Hz, 1H), 7.77 (dd, J ¼ 7.5 Hz, 1.5 Hz, 1H), 7.74 (dd, J ¼ 8.0,
oxime acetate 1g (59 mg, 0.3 mmol), phenylacetic acid 2a 1.0 Hz, 1H), 7.49–7.42 (m, 4H). 13C NMR (125 MHz, CDCl3, ppm)
(27 mg, 0.2 mmol). Aer column chromatography (hexane/ d 169.1, 155.2, 140.8, 135.4, 135.3, 132.9, 131.7, 131.5, 130.4,
dichloromethane ¼ 2 : 1), 51 mg (89%) of a white solid was 126.5, 125.7, 124.7, 124.3, 121.8. HRMS (ESI+) m/z calculated for
+
obtained. This compound is known.6c Mp ¼ 140–142 C. Rf ¼
C
15H9N2O2S2 (M + H)+ 313.0100, found 313.0104. One carbon
ꢀ
0.35 (hexane/dichloromethane ¼ 2 : 1). 1H NMR (500 MHz, signal could not be located.
CDCl3, ppm) d 8.21 (dd, J ¼ 9.0 Hz, 5.0 Hz, 1H), 8.03 (d, J ¼
8.0 Hz, 1.5 Hz, 2H), 7.53–7.46 (m, 3H), 7.25 (d, J ¼ 10 Hz, 2.5 Hz,
1H, overlapping with CHCl3 signal). 13C NMR (125 MHz, CDCl3,
Conflicts of interest
ppm) d 171.0, 160.8 (d, 1JC–F ¼ 245.6 Hz), 155.3, 143.6 (d, 3JC–F
¼
The authors declare no competing nancial interest.
4
10.0 Hz), 133.9, 130.4, 129.8 (d, JC–F ¼ 2.9 Hz), 129.1, 127.1,
126.6, 122.7 (d, 3JC–F ¼ 9.2 Hz), 113.8 (d, 2JC–F ¼ 23.9 Hz), 110.0
2
(d, JC–F ¼ 25.8 Hz).
Acknowledgements
2,5-Diphenylthieno[3,2-d]thiazole (3ha, Scheme 3): following the
general procedure A. (2E,3E)-4-Phenylbut-3-en-2-one O-acetyl
oxime 1h (61 mg, 0.3 mmol), phenylacetic acid 2a (27 mg, 0.2
The Vietnam National University - Ho Chi Minh City (VNU-
HCM) is acknowledged for nancial support via project no.
NCM2019-20-01.
mmol).
Aer
column
chromatography
(hexane/
dichloromethane ¼ 4 : 1), 47 mg (81%) of a white solid was
obtained. This compound is known.6a Mp ¼ 195–197 C. Rf ¼
ꢀ
References
0.31 (hexane/dichloromethane ¼ 4 : 1). 1H NMR (500 MHz,
CDCl3, ppm) d 7.92 (dd, J ¼ 8.0 Hz, 1.0 Hz, 2H), 7.63 (s, 1H), 7.57 1 For selected examples, see:(a) F. Kakiuchi, S. Kan, K. Igi,
(d, J ¼ 7.5 Hz, 2H), 7.42–7.34 (m, 5H), 7.27 (t, J ¼ 7.5 Hz, 1H). 13
C
N. Chatani and S. Murai, J. Am. Chem. Soc., 2003, 125, 1698;
(b) N. Kimura, T. Kochi and F. Kakiuchi, J. Am. Chem. Soc.,
2017, 139, 14849; (c) R.-Y. Zhu, Z.-Q. Li, H. S. Park,
C. H. Senanayake and J.-Q. Yu, J. Am. Chem. Soc., 2018, 140,
3564; (d) D. Xing, X. Qi, D. Marchant, P. Liu and G. Dong,
Angew. Chem., Int. Ed., 2019, 58, 4366; (e) S. St John-
Campbell, A. J. P. White and J. A. Bull, Chem. Sci., 2017, 8,
4840; (f) Q.-J. Yao, S. Zhang, B.-B. Zhan and B.-F. Shi,
Angew. Chem., Int. Ed., 2017, 56, 6617; (g) B. Li, K. Seth,
B. Niu, L. Pan, H. Yang and H. Ge, Angew. Chem., Int. Ed.,
2018, 57, 3401; (h) X.-Y. Chen and E. Sorensen, J. Chem. Sci.,
2018, 9, 8951; (i) W. Xu and N. Yoshikai, Org. Lett., 2018, 20,
1392; (j) Y. Hu, B. Zhou, H. Chen and C. Wang, Angew.
Chem., Int. Ed., 2018, 57, 12071.
NMR (125 MHz, CDCl3, ppm) d 170.7, 161.6, 147.8, 134.4, 133.8,
130.5, 129.5, 129.1, 128.2, 126.7, 125.8, 114.8. One carbon signal
could not be located.
4-(4-Fluorophenyl)-5H-1,2,3-dithiazole-5-thione (5g, Scheme 4).
To an 8 mL screw-cap vial was added 4-uoroacetophenone
ketoxime acetate 1g (71 mg, 0.4 mmol), Li2CO3 (15 mg, 0.2
mmol), elemental sulfur (32 mg, 1 mmol), and DMSO (0.5 mL).
The vial was stirred at 120 ꢀC for 12 h. Upon completion of the
reaction, the mixture was cooled to room temperature, and
NaHCO3 (5% aqueous solution, 2 mL) was added. The organic
components were consequently extracted into ethyl acetate (3 ꢂ
2 mL), washed with brine (2 ꢂ 1 mL), dried over anhydrous
Na2SO4, ltered, and concentrated in vacuo. The residue was
puried by column chromatography on silica gel (hexane/ 2 For review, see:(a) H. Huang, X. Ji, W. Wu and H. Jiang, Chem.
dichloromethane 10 : 1) to afford 66 mg (72%) of a brown
Soc. Rev., 2015, 44, 1155Selected examples:(b) L. V. Desai,
H. A. Malik and M. S. Sanford, Org. Lett., 2006, 8, 1141; (c)
J. M. Neely and T. Rovis, J. Am. Chem. Soc., 2013, 135, 66;
(d) B. Ye and N. Cramer, Angew. Chem., Int. Ed., 2014, 53,
7896; (e) H. Zhang, K. Wang, B. Wang, H. Yi, F. Hu, C. Li,
Y. Zhang and J. Wang, Angew. Chem., Int. Ed., 2014, 53,
13234; (f) B. Sun, T. Yoshino, M. Kanai and S. Matsunaga,
Angew. Chem., Int. Ed., 2015, 54, 12968; (g) Y. Li, H. Chen,
L.-B. Qu, K. N. Houk and Y. Lan, ACS Catal., 2019, 9, 7154.
solid. This compound is known.9 Rf
¼
0.72 (hexane/
1
ꢀ
dichloromethane 2 : 1). Mp ¼ 150–152 C. H NMR (500 MHz,
CDCl3, ppm) d 7.98–7.95 (m, 2H), 7.16–7.12 (m, 2H). 13C NMR
1
(125 MHz, CDCl3, ppm) d 207.9, 166.7, 164.0 (d, JC–F ¼ 251.9
Hz), 131.7 (d, 3JC–F ¼ 8.5 Hz), 127.5 (d, 4JC–F ¼ 3.5 Hz), 115.2 (d,
2JC–F ¼ 21.7 Hz).
2-(2-Nitrophenyl)benzo[4,5]thieno[3,2-d]thiazole (7, Scheme 6).
To a 25 mL Schlenk tube was added 2-phenylbenzo[4,5]thieno
[3,2-d]thiazole (53 mg, 0.2 mmol), Fe(NO3)3$9H2O (162 mg, 0.4 3 (a) S. Liu and L. S. Liebeskind, J. Am. Chem. Soc., 2008, 130,
mmol), anhydrous CuCl2 (5.4 mg, 0.04 mmol), K2S2O8 (108 mg,
0.4 mmol), and 1,2-dichloroethane (3 mL). The reaction mixture
was stirred at 100 ꢀC for 8 h in an oil bath. Aer cooling to room
temperature, the mixture was diluted with chloroform (15 mL)
and ltered through a short pad of silica gel. The organic layer
was washed with brine (2 ꢂ 5 mL), dried over anhydrous
6918; (b) Z.-H. Ren, Z.-Y. Zhang, B.-Q. Yang, Y. Y. Wang and
Z.-H. Guan, Org. Lett., 2011, 13, 5394; (c) Y. Wei and
N. Yoshikai, J. Am. Chem. Soc., 2013, 135, 3756; (d)
H. Huang, J. Cai, X. Ji, F. Xiao, Y. Chen and G.-J. Deng,
Angew. Chem., Int. Ed., 2016, 55, 307; (e) C. Zhu, R. Zhu,
H. Zeng, F. Chen, C. Liu, W. Wu and H. Jiang, Angew.
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RSC Adv., 2020, 10, 11024–11032 | 11031