10.1002/cplu.201700486
ChemPlusChem
ARTICLE
2, 472-485; b) V. B. F. Custodis, P. Hemberger, Z. Ma, J. A. van
Bokhoven, J. Phys. Chem. B. 2014, 118, 8524-8531; c) V. E. Tarabanko,
D. V. Petukhov, G. E. Selyutin, Kinet. Catal. 2004, 45, 569-577; d) S.
Nanayakkara, A. F. Patti, K. Saito, Green Chem. 2014, 16, 1897-1903.
[11] W. E. S. Hart, L. Aldous, J. B. Harper, Org. Biomol. Chem. 2017, 15,
5556-5563.
[12] The concentration of the acid was kept constant throughout. Changing
this concentration will change the extent of protonation of the the starting
materials, as discussed below and previously (reference 11). Importantly,
the concentration is significantly larger than the concentration of the
model compound present.
[13] In the previous work, all reactions were carried out at 343 K. As will be
noted here, the greater difference in the relative rate of reactions at the
different sites mean that that multiple temperatures were necessary.
[14] W. E. S. Hart, J. B. Harper and L. Aldous, Green Chem. 2015, 17, 214-
218.
[15] During the review process, it was noted that there is the potential for
bridged interactions with other electron deficient species (such as a
pyridinium cation). Whilst this can not explicitly be ruled out by the
experimental data, it is considered that the comparatively large steric
requirements make protonation the most likely explaination here.
[16] The formation of a hydrogen bonded bridged species is well-described in
literature, with distances between electronegative atoms up to ca. 3 Å.[22]
The geometrical constraints in compound 4 (the distance between the
relevant oxygen atoms in compound 4 is ca. 4.8 Å) and the steric
requirements of the benzene ring mean a hydrogen bond as in Figure 4 is
extremely unlikely.
References and notes
[1] J. Zakzeski, P. C. A. Bruijnincx, A. L. Jongerius, B. M. Weckhuysen,
Chem. Rev. 2010, 110, 3552-3599.
[2] F. S. Chakar, A. J. Ragauskas, Ind. Crops Prod. 2004, 20, 131-141.
[3] a) A. Brandt, J. Grasvik, J. P. Hallett, T. Welton, Green Chem. 2013, 15,
550-583; b) M. M. Hossain, L. Aldous, Aust. J. Chem. 2012, 65, 1465-
1477; c) W. X. Teh, M. M. Hossain, T. Q. To, L. Aldous, ACS Sustainable
Chem. Eng. 2015, 3, 992-999.
[4] a) H. M. Yau, S. T. Keaveney, B. J. Butler, E. E. L. Tanner, M. S. Guerry,
S. R. D. George, M. H. Dunn, A. K. Croft, J. B. Harper, Pure Appl. Chem.
2013, 85, 1979-1990; b) S. T. Keaveney, R. S. Haines, J. B. Harper, in
Encyclopedia of Physical Organic Chemistry, Wiley, 2017, p. 1411; c) J. P.
Hallett, T. Welton, Chem. Rev. 2011, 111, 3508-3576; d) S. T. Keaveney,
R. S. Haines, J. B. Harper, Pure Appl. Chem. 2017, 86, 745-757.
[5] a) J. B. Binder, M. J. Gray, J. F. White, Z. C. Zhang, J. E. Holladay,
Biomass Bioenerg. 2009, 33, 1122-1130; b) M. Scott, P. J. Deuss, J. G.
de Vries, M. H. G. Prechtl, K. Barta, Catal. Sci. Technol. 2016, 6, 1882-
1891; c) A. W. Pelzer, M. R. Sturgeon, A. J. Yanez, G. Chupka, M. H.
O’Brien, R. Katahira, R. D. Cortright, L. Woods, G. T. Beckham, L. J.
Broadbelt, ACS Sustainable Chem. Eng. 2015, 3, 1339-1347; d) A.
Rahimi, A. Ulbrich, J. J. Coon, S. S. Stahl, Nature 2014, 515, 249-252.
[6] a) S. Jia, B. J. Cox, X. Guo, Z. C. Zhang, J. G. Ekerdt, ChemSusChem
2010, 3, 1078-1084; b) B. J. Cox, S. Jia, Z. C. Zhang, J. G. Ekerdt, Polym.
Degrad. Stabil. 2011, 96, 426-431; c) G. F. De Gregorio, C. C. Weber, J.
Grasvik, T. Welton, A. Brandt, J. P. Hallett, Green Chem. 2016, 18, 5456-
5465.
[17] J. Clayden, N. Greeves, S. Warren, P. Wothers, Organic Chemistry, OUP
Oxford, Oxford, 2001.
[18] C. G. Swain, E. C. Lupton, J. Am. Chem. Soc. 1968, 90, 4328-4337.
[19] Bromination of electron rich arenes by bromine generated
photochemically in situ is a possibility. However, the protonation of the
systems would dramatically reduce their reactivity and the samples are
not exposed to sunlight so it is considered that nucleophilic attack is most
likely.
[7] R. Prado, A. Brandt, X. Erdocia, J. Hallet, T. Welton, J. Labidi, Green
Chem. 2016, 18, 834-841.
[8] S. Jia, B. J. Cox, X. Guo, Z. C. Zhang, J. G. Ekerdt, Ind. Eng. Chem. Res.
2011, 50, 849-855.
[9] a) M. P. Pandey, C. S. Kim, Chem. Eng. Technol. 2011, 34, 29-41; b) H.
Wang, M. Tucker, Y. Ji, J. Appl. Chem. 2013, 2013, 9; c) H. Lange, S.
Decina, C. Crestini, Eur. Polym. J. 2013, 49, 1151-1173; d) C. Li, X. Zhao,
A. Wang, G. W. Huber, T. Zhang, Chem. Rev. 2015, 115, 11559-11624.
[10] a) M. R. Sturgeon, S. Kim, K. Lawrence, R. S. Paton, S. C. Chmely, M.
Nimlos, T. D. Foust, G. T. Beckham, ACS Sustainable Chem. Eng. 2014,
[20] L. L. Tolstikova, B. A. Shainyan, Russ. J. Org. Chem. 2006, 42, 1068-
1074.
[21] J.-w. Zhang, Y. Cai, G.-p. Lu, C. Cai, Green Chem. 2016, 18, 6229-6235.
[22] G. R. Desiraju, T. Steiner, The Weak Hydrogen Bond in Structural
Chemistry and Biology, Oxford University Press, Oxford, 1999.
This article is protected by copyright. All rights reserved.