Edge Article
Chemical Science
Ed., 2013, 52, 2239; (h) S. O'Sullivan, E. Doni, T. Tuttle and 10 D. Chen, G. Xu, Q. Zhou, L. W. Chung and W. Tang, J. Am.
J. A. Murphy, Angew. Chem., Int. Ed., 2014, 53, 474; (i) Chem. Soc., 2017, 139, 9767.
E. Doni, B. Mondal, S. O'Sullivan, T. Tuttle and 11 For a review, see: (a) E. M. Kosower, Top. Curr. Chem., 1983,
J. A. Murphy, J. Am. Chem. Soc., 2013, 135, 10934; (j)
S. S. Hanson, E. Doni, K. T. Traboulsee, G. Coulthard,
J. A. Murphy and C. A. Dyker, Angew. Chem., Int. Ed., 2015,
54, 11236.
112, 117; For examples, see: (b) E. M. Kosower and
J. L. Cotter, J. Am. Chem. Soc., 1964, 86, 5524; (c) R. J. Gale
and R. A. Osteryoung, J. Electrochem. Soc., 1980, 127, 2167;
¨
(d) F. Pragst and R. Stoßer, Z. Chem., 1985, 25, 222; (e)
ˇ
ˇ
˚
F. Pragst and M. Santrucek, Adv. Synth. Catal., 1987, 329, 67.
5 For selected mechanistic study of “super electron donors” as
reactive intermediates, see: (a) A. Studer and D. P. Curran, 12 M. Grandl, B. Rudolf, Y. Sun, D. F. Bechtel, A. J. Pierik and
Angew. Chem., Int. Ed., 2011, 50, 5018; (b) A. Studer and F. Pammer, Organometallics, 2017, 36, 2527.
D. P. Curran, Nat. Chem., 2014, 6, 765; (c) S. Zhou, 13 The simulation of the experimental EPR spectra was
G. M. Anderson, B. Mondal, E. Doni, V. Ironmonger,
M. Kranz, T. Tuttle and J. A. Murphy, Chem. Sci., 2014, 5,
performed using the EasySpin soware package. See:
S. Stoll and A. Schweiger, J. Magn. Reson., 2006, 178, 42.
476; (d) S. Zhou, E. Doni, G. M. Anderson, R. G. Kane, 14 A mixed solution of complexes 4 and 10, prepared by the
S. W. MacDougall, V. M. Ironmonger, T. Tuttle and
J. A. Murphy, J. Am. Chem. Soc., 2014, 136, 17818; (e) H. Yi,
A. Jutand and A. Lei, Chem. Commun., 2015, 51, 545; (f)
M. Patil, J. Org. Chem., 2016, 81, 632; (g) J. P. Barham,
G. Coulthard, R. G. Kane, N. Delgado, M. P. John and
J. A. Murphy, Angew. Chem., Int. Ed., 2016, 55, 4492; (h)
reaction between complex 4 and MeOBpin (see Scheme 8
and the ESI for details†), was used as the UV-vis sample in
this study, because we were not able to isolate the pure
form of complex 10. Despite that, the existence of other
species did not interfere with the assignment of the
characteristic absorption bands of complex 10.
L. Zhang, H. Yang and L. Jiao, J. Am. Chem. Soc., 2016, 138, 15 For full citation of Gaussian 09, see the ESI.†
7151; (i) J. P. Barham, G. Coulthard, K. J. Emery, E. Doni, 16 (a) Y. Zhao and D. G. Truhlar, Theor. Chem. Acc., 2008, 120,
F. Cumine, G. Nocera, M. John, L. E. A. Berlouis,
T. McGuire, T. Tuttle and J. Murphy, J. Am. Chem. Soc.,
215; (b) Y. Zhao and D. G. Truhlar, Acc. Chem. Res., 2008,
41, 157.
2016, 138, 7402; (j) M. Li, O. Gutierrez, S. Berritt, 17 (a) V. Barone and M. Cossi, J. Phys. Chem. A, 1998, 102, 1995;
A. Pascual-Escudero, A. Ye¸silçimen, X. Yang, J. Adrio,
G. Huang, E. Nakamura-Ogiso, M. C. Kozlowski and
(b) M. Cossi, N. Rega, G. Scalmani and V. Barone, J. Comput.
Chem., 2003, 24, 669.
P. J. Walsh, Nat. Chem., 2017, 9, 997; (k) M. Li, S. Berritt, 18 (a) G. Wang, H. Zhang, J. Zhao, W. Li, J. Cao, C. Zhu and S. Li,
L. Matuszewski, G. Deng, A. Pascual-Escudero,
G. B. Panetti, M. Poznik, X. Yang, J. J. Chruma and
P. J. Walsh, J. Am. Chem. Soc., 2017, 139, 16327; (l) H. Yang,
L. Zhang and L. Jiao, Chem.–Eur. J., 2017, 23, 65.
6 L. Zhang and L. Jiao, J. Am. Chem. Soc., 2017, 139, 607.
7 For a review, see: (a) E. C. Neeve, S. J. Geier, I. A. Mkhalid,
S. A. Westcott and T. B. Marder, Chem. Rev., 2016, 116,
9091; For examples employing diborons as reducing
Angew. Chem., Int. Ed., 2016, 55, 5985; (b) G. Wang, J. Cao,
L. Gao, W. Chen, W. Huang, X. Cheng and S. Li, J. Am.
Chem. Soc., 2017, 139, 3904.
19 (a) C. Kleeberg, L. Dang, Z. Li and T. B. Marder, Angew.
Chem., Int. Ed., 2009, 48, 5350; (b) S. Pietsch, E. C. Neeve,
D. C. Apperley, R. Bertermann, F. Mo, D. Qiu,
M. S. Cheung, L. Dang, J. Wang, U. Radius, Z. Lin,
C. Kleeberg and T. B. Marder, Chem.–Eur. J., 2015, 21, 7082.
agents, see: (b) S. Bae and M. K. Lakshman, J. Org. Chem., 20 For selected examples of the transition-metal-free heterolytic
2008, 73, 1311; (c) H. P. Kokatla, P. F. Thomson, S. Bae,
V. R. Doddi and M. K. Lakshman, J. Org. Chem., 2011, 76,
7842; (d) H. Lu, Z. Geng, J. Li, D. Zou, Y. Wu and Y. Wu,
Org. Lett., 2016, 18, 2774; (e) K. Yang, F. Zhou, Z. Kuang,
G. Gao, T. G. Driver and Q. Song, Org. Lett., 2016, 18, 4088;
(f) M. Flinker, H. Yin, R. W. Juhl, E. Z. Eikeland,
J. Overgaard, D. U. Nielsen and T. Skrydstrup, Angew.
Chem., Int. Ed., 2017, 56, 15910.
8 Single crystals of 4$DME were obtained by diffusion of
solutions of B2pin2 (in hexane) and radical anion 3
(contained excess 2, in DME) at 25 ꢁC. Due to the labile
nature of this complex, the obtained crystals are of
insufficient qualities despite several attempts. Thus the
quality of the acquired diffraction data was slightly below
the average level (see the attached CIF le for details).
Despite that, the present X-ray diffraction data conrmed
the chemical structure of 4$DME unambiguously.
cleavage of boron–boron bond, see: (a) K. Lee,
A. R. Zhugralin and A. H. Hoveyda, J. Am. Chem. Soc., 2009,
´
´
131, 7253; (b) A. Bonet, H. Gulyas and E. Fernandez,
Angew. Chem., Int. Ed., 2010, 49, 5130; (c) J. M. O'Brien and
A. H. Hoveyda, J. Am. Chem. Soc., 2011, 133, 7712; (d)
´
A. Bonet, C. Pubill-Ulldemolins, C. Bo, H. Gulyas and
´
E. Fernandez, Angew. Chem., Int. Ed., 2011, 50, 7158; (e)
´
´
´
C. Sole, H. Gulyas and E. Fernandez, Chem. Commun.,
2012, 48, 3769; (f) K. Oshima, T. Ohmura and
M. Suginome, Chem. Commun., 2012, 48, 8571; (g)
´
C. Pubill-Ulldemolins, A. Bonet, C. Bo, H. Gulyas and
´
E. Fernandez, Chem.–Eur. J., 2012, 18, 1121; (h) H. Wu,
S. Radomkit, J. M. O'Brien and A. H. Hoveyda, J. Am. Chem.
Soc., 2012, 134, 8277; (i) T. P. Blaisdell, T. C. Caya,
L. Zhang, A. Sanz-Marco and J. P. Morken, J. Am. Chem.
Soc., 2014, 136, 9264; (j) L. Fang, L. Yan, F. Haeffner and
J. P. Morken, J. Am. Chem. Soc., 2016, 138, 2508; (k)
C. Kojima, K. H. Lee, Z. Lin and M. Yamashita, J. Am.
Chem. Soc., 2016, 138, 6662; (l) Y. Katsuma, H. Asakawa,
K.-H. Lee, Z. Lin and M. Yamashita, Organometallics, 2016,
9 W. Maringgele, A. Meller, S. Dielkus and R. Herbst-Irmer, Z.
Naturforsch., B: J. Chem. Sci., 1993, 48, 561.
This journal is © The Royal Society of Chemistry 2018
Chem. Sci.