UPDATES
´
Junta de Castilla y Leon and FEDER (BU076U16) for
financial support. R. R.-P. thanks Universidad de Burgos for
a predoctoral contract.
[12] N. Garcꢂa, P. Garcꢂa-Garcꢂa, M. A. Fernꢁndez-Rodrꢂ-
guez, R. Rubio, M. R. Pedrosa, F. J. Arnꢁiz, R. Sanz,
Adv. Synth. Catal. 2012, 354, 321–327.
1
2
3
[13] This transformation also works in DMF, toluene or
MeCN, although cleaner processes were observed in
DMA as solvent. See Supporting Information for de-
tails.
[14] S. Asako, T. Sakae, M. Murai, K. Takai, Adv. Synth.
Catal. 2016, 358, 3966–3970.
harvard.edu/pdf/evans_pKa_table.pdf (accessed January
2017).
[16] For a review, see: a) X.-M. Peng, G.-X. Cai, C.-H. Zhou,
Curr. Top. Med. Chem. 2013, 13, 1963–2010. For
selected examples, see: b) J. Fu, Y. Yang, X.-W. Zhang,
W.-J. Mao, Z.-M. Zhang, H.-L. Zhu, Bioorg Med. Chem.
2010, 18, 8457–8462; c) K. Takahashi, G. Yamagishi, T.
Hiramatsu, A. Hosoya, K. Onoe, H. Doi, H. Nagata, Y.
Wada, H. Onoe, Y. Watanabe, T. Hosoya, Bioorg. Med.
Chem. 2011, 19, 1464–1470.
[17] a) R. E. Damschroder, W. D. Peterson, Org. Synth.
1940, 20, 16–17; For a continuous-flow synthesis of 1-
substituted benzotriazoles also based on diazotization/
cyclization, see: b) M. Chen, S. L. Buchwald, Angew.
Chem. Int. Ed. 2013, 52, 4247–4250.
[18] See, for instance: a) A. J. Boulton, P. B. Ghosh, A. R.
Katritzky, J. Chem. Soc. B 1966, 1004–1011; b) C. W.
Rees, A. A. Sale, Chem. Commun. 1971, 532.
[19] V. Gurram, H. K. Akula, R. Garlapati, N. Pottabathini,
M. K. Lakshman, Adv. Synth. Catal. 2015, 357, 451–462.
[20] B. Yu, Z. Huang, M. Zhang, D. R. Dillard, H. Ji, ACS
Chem. Biol. 2013, 8, 524–529.
4
5
6
7
8
9
References
[1] T. Eicher, S. Hauptmann, The Chemistry of Hetero-
cycles, Wiley-VCH, Weinheim, 2003.
[2] Y. Wang, L. Zhang, Synthesis 2015, 47, 289–305.
[3] a) L. Zhang, Acc. Chem. Res. 2014, 47, 877–888; b) H.-S.
Yeom, S. Shin, Acc. Chem. Res. 2014, 47, 966–977.
[4] For a review, see: G. Yan, A. J. Borah, M. Yang, Adv.
Synth. Catal. 2014, 356, 2375–2394.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
[5] See, for instance: a) Y. Wang, J. H. Espenson, Org. Lett.
2000, 2, 3525–3526; b) J. S. Yadav, B. V. Subba Reddy,
M. Muralidhar Reddy, Tetrahedron Lett. 2000, 41, 2663–
2665: c) R. Sanz, J. Escribano, Y. Fernꢁndez, R. Aguado,
M. R. Pedrosa, F. J. Arnꢁiz, Synlett 2005, 1389–1392;
d) H.-R. Bjørsvik, C. Gambarotti, V. R. Jensen, R.
Rodrꢂguez-Gonzꢁlez, J. Org. Chem. 2005, 70, 3218–
3224; e) S. Kumar, A. Saini, J. S. Sandhu, Tetrahedron
Lett. 2005, 46, 8737–8739; f) B. W. Yoo, J. W. Choi, C. M.
Yoon, Tetrahedron Lett. 2006, 47, 125–126; g) A. Saini,
S. Kumar, J. S. Sandhu, Synlett 2006, 395–398; h) S. K.
Singh, M. S. Reddy, M. Mangle, K. R. Ganesh, Tetrahe-
dron 2007, 63, 126–130; i) M. Toganoh, K. Fujino, S.
Ikeda, H. Furuta, Tetrahedron Lett. 2008, 49, 1488–1491;
j) H. P. Kokatla, P. F. Thomson, S. Bae, V. R. Doddi,
M. K. Lakshman, J. Org. Chem. 2011, 76, 7842–7848;
k) A. T. Londregan, D. W. Piotrowski, J. Xiao, Synlett
2013, 24, 2695–2700; l) J. Jeong, D. Lee, S. Chang,
Chem. Commun. 2015, 51, 7035–7038; m) S. Gupta, P.
Sureshbabu, A. K. Singh, S. Sabiah, J. Kandasamy,
Tetrahedron Lett. 2017, 58, 909–913.
[21] See, for instance: K. Schiemann, H. D. H. Showalter, J.
Org. Chem. 1999, 64, 4972–4975.
[22] F. T. Boyle, R. A. Y. Jones, J. Chem. Soc., Perkin Trans.
2 1973, 160–164.
[6] For a review on applications of dioxomolydenum(VI)
complexes in organic synthesis, see: R. Sanz, M. R.
Pedrosa, Curr. Org. Synth. 2009, 6, 239–263.
[23] M. Boiani, L. Boiani, A. Denicola, S. Torres de Ortiz, E.
Serna, N. Vera de Bilbao, L. Sanabria, G. Yaluff, H.
Nakayama, A. Rojas de Arias, C. Vega, M. Rolan, A.
Gꢃmez-Barrio, H. Cerecetto, M. Gonzꢁlez, J. Med.
Chem. 2006, 49, 3215–3224.
[24] Easily accessible from aryl glyoxals oximes and ketones,
see: M. V. Varaksin, I. A. Utepova, O. N. Chupakhin,
V. N. Charushin, J. Org. Chem. 2012, 77, 9087–9093.
[25] Conveniently prepared from glyoxal phenylhydrazone,
see: M. Begtrup, J. Holm, J. Chem. Soc. Perkin Trans. 1
1981, 503–513.
[7] It should be noted that MoO2Cl2(dmf)2 is a readily
available catalyst that can be easily prepared at a very
low cost in gram quantities, from inexpensive Mo
sources such as MoO3 (50–70 E/mol, see: F. J. Arnꢁiz,
Inorg. Synth. 1997, 31, 246–247) or Na2MoO4 (75–100 E/
mol, see ref. [8]).
[8] R. Sanz, J. Escribano, R. Aguado, M. R. Pedrosa, F. J.
Arnꢁiz, Synthesis 2004, 1629–1632.
[9] R. Sanz, J. Escribano, M. R. Pedrosa, R. Aguado, F. J.
Arnꢁiz, Adv. Synth. Catal. 2007, 349, 313–318.
[26] For an alternative deoxygenation of 2H-imidazole 1-
oxides with Si2Cl6, see: A. G. Hortmann, J.-Y. Koo, C.-C.
Yu, J. Org. Chem. 1978, 43, 2289–2291.
[10] For other Mo-catalyzed reductions using alternative
reductants such as boranes, silanes or hydrogen, see:
a) A. C. Fernandes, C. C. Rom¼o, Tetrahedron 2006, 62,
9650–9654; b) A. C. Fernandes, C. C. Rom¼o, Tetrahe-
dron Lett. 2007, 48, 9176–9179; c) P. M. Reis, P. J. Costa,
C. C. Rom¼o, J. A. Fernandes, M. J. Calhorda, B. Royo,
Dalton Trans. 2008, 1727–1733; d) P. M. Reis, B. Royo,
Tetrahedron Lett. 2009, 50, 949–952.
[27] J. Cymerman Craig, K. K. Purushothaman, J. Org.
Chem. 1970, 35, 1721–1722.
[28] The oxidative cleavage of diols catalyzed by [MoO2]2+
in which DMSO reoxidizes a Mo(IV) species also
supports the proposed A to B transformation. See: N.
Garcꢂa, R. Rubio-Presa, P. Garcꢂa-Garcꢂa, M. A.
Fernꢁndez-Rodrꢂguez, M. R. Pedrosa, F. J. Arnꢁiz, R.
Sanz, Green Chem. 2016, 18, 2335–2340.
[11] N. Garcꢂa, P. Garcꢂa-Garcꢂa, M. A. Fernꢁndez-Rodrꢂ-
guez, D. Garcꢂa, M. R. Pedrosa, F. J. Arnꢁiz, R. Sanz,
Green Chem. 2013, 15, 999–1005.
Adv. Synth. Catal. 2017, 359, 1–8
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