Page 5 of 7
ACS Catalysis
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
sequential addition of Zn(OTf)2 and terpyridine into 1b/2
CHCl /CH CN (2 : 1, v/v)).
Notes
(
The authors declare no completing interest.
3
3
ACKNOWLEDGMENT
Finally, dynamic property of the nonꢀcovalent Pt complex
1b/2 was exploited, which provided an extra control over their
photoꢀcatalytic efficiency. As previously reported by Lehn et
al., terpyridine and its derivatives are capable of displaying
This work was supported by the National Natural Science Founꢀ
dation of China (21674106), the Fundamental Research Funds for
the Central Universities (WK3450000001), and CAS Youth Innoꢀ
vation Promotion Association (2015365).
2+
36ꢀ39
Zn ionꢀcontrolled nanomechanical motion.
Herein, upon
adding 2 equivalent of Zn(OTf) , conformational switch from
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
2
Uꢀ to Wꢀshape occurs for 1b (Scheme 1 and Figure S21). As a
consequence, breakup of tetraꢀnuclear Pt complex 1b/2 can be
directly reflected by 3ꢀfold decrease of MMLCT absorbance
intensity (λ = 563 nm, Figure 4a). Such phenomena denote the
REFERENCES
1
. Prier, C. K.; Rankic, D. A.; MacMillan, D. W. Chem. Rev. 2013,
113, 5322–5363.
2. Hoeben, F. J. M.; Jonkhejim, P.; Meijer, E. W.; Schenning, A. P.
H. J. Chem. Rev. 2005, 105, 1491–1546.
2+
structural conversion from 1b/2 to 1b•Zn /2 (Scheme 1 and
3
. Yan, X.; Cook, T. R.; Wang, P.; Huang, F.; Stang, P. J. Nat.
Chem. 2015, 7, 342–348.
. Niu, Z.; Huang, F.; Gibson, H. W. J. Am. Chem. Soc. 2011, 133,
836–2839.
. Biedermann, F.; Elmalem, E.; Ghosh, I.; Nau, W. M.; Scherman,
Figure S22). Simultaneously, no conversion from amine 3 to
imine 4 can be detected (Figure 4b). Deactivation of the phoꢀ
tocatalytic efficiency should be primarily ascribed to the
4
2
disruption of tetraꢀnuclear Pt(II)ꢀPt(II) interactions involved in
5
1
1
b/2, thus preventing O generation for the resulting complex
2
O. A. Angew. Chem., Int. Ed. 2012, 51, 4185–4189.
2
+
41
1b•Zn /2 (Figure S23). When unsubstituted terpyridine (4
equivalence) was subsequently added and served as the comꢀ
petitive ligand, the original MMLCT signals completely reꢀ
store (Figure 4a), accompanying with the reꢀactivation of phoꢀ
tocatalytic efficiency (Figure 4b and Figure S24). Remarkably,
attributed to the fully reversibility of 1b/2 (Figure 4a, inset),
6. Liu, K.; Liu, Y.ꢀL.; Yao, Y.ꢀX.; Yuan, H.ꢀX.; Wang, S.; Wang,
Z.ꢀQ.; Zhang, X. Angew. Chem., Int. Ed. 2013, 52, 8285–8289.
7. Sambe, L.; de La Rosa, V. R.; Belal, K.; Stoffelbach, F.; Lyskaꢀ
wa, J.; Delattre, F.; Bria, M.; Cooke, G.; Hoogenboom, R.; Woisel, P.
Angew. Chem., Int. Ed., 2014, 53, 5044–5048.
8
. Jiao, Y.; Li, W.ꢀL.; Xu, J.ꢀF.; Wang, G.ꢀT.; Li, J.; Wang, Z.ꢀQ.;
Zhang, X. Angew. Chem., Int. Ed., 2016, 55, 8933–8937.
9. Shi, B.; Jie, K.; Zhou, Y.; Zhou, J.; Xia, D.; Huang, F. J. Am.
Chem. Soc. 2016, 138, 80–83.
sequential addition of Zn(OTf) and terpyridine enables the
2
revival and loss of the photoꢀcatalytic properties for several
repeated cycles (Figure 4b).
1
0. Würthner, F.; Kaiser, T. E.; SahaꢀMoeller, C. R. Angew. Chem.,
Int. Ed. 2011, 50, 3376–3410.
1. Frischmann, P. D.; Mahata, K.; Würthner, F. Chem. Soc. Rev.
1
Conclusion
2
013, 42, 1847–1870.
In summary, herein we have demonstrated the first example
of supramolecular photosensitizers and photocatalysts derived
from discrete Pt(II)···Pt(II) metal–metal complexation. The
designed Pt complexes 1a–b/2 not only display strong binding
12. Hou, L.ꢀL.; Zhang, X.ꢀY.; Pijper, T. C.; Browne, W. R.; Ferinꢀ
ga, B. L. J. Am. Chem. Soc. 2014, 136, 910–913.
3. Wong, K. M.ꢀC.; Yam, V. W.ꢀW. Acc. Chem. Res. 2011, 44,
24–434.
4. To, W.ꢀP.; Zou, T; Sun, R. W.ꢀY.; Che, C.ꢀM. Phil. Trans. R.
Soc. A 2013, 371, 20120126.
5. Aliprandi, A.; Mauro, M.; De Cola, L. Nat. Chem. 2016, 8, 10–
1
4
1
strength, but also feature bathochromicꢀshifted MMLCT tranꢀ
1
sition signals, both of which are crucial for their excellent O2
1
15.
generation capabilities upon lowꢀenergy visible light irradiaꢀ
tion. More importantly, when terpyridine moiety is embedded
in the rigid backbone of 1b, breakup of tetraꢀnuclear
Pt(II)···Pt(II) complexation can be achieved upon adding
16. Yam, V. W.ꢀW.; Au, V. K.ꢀM.; Leung, S. Y.ꢀL. Chem. Rev.
2015, 115, 7589–7728.
1
7. Leung, S. Y.ꢀL.; Tam, A. Y.ꢀY.; Tao, C.ꢀH.; Chow, H. S.; Yam,
V. W.ꢀW. J. Am. Chem. Soc. 2012, 134, 1047–1056.
8. Yamada, Y.; Mihara, N.; Shibano, S.; Sugimoto, K.; Tanaka, K.
J. Am. Chem. Soc. 2013, 135, 11505–11508.
9. Li, K.; Tong, G. S. M.; Wan, Q.; Cheng, G.; Tong, W.ꢀY.; Ang,
W.ꢀH.; Kwong, W.ꢀL.; Che, C.ꢀM. Chem. Sci. 2016, 7, 1653–1673.
0. Yuen, M.ꢀY.; Roy, V. A. L.; Lu, W.; Kui, S. C. F.; Tong, G. S.
Zn(OTf) to the resulting supramolecular photosensitizer 1b/2.
2
1
Consequently, photoꢀoxidation of secondary amine to the
corresponding imine can be precisely deactivated/reactivated,
1
upon the sequential addition of Zn(OTf) and unsubstituted
2
terpyridine as the competitive ligand. Hence, the current sysꢀ
tem opens up a new avenue toward smart photocatalytic mateꢀ
rials via elaborate supramolecular design.
2
M.; So, M.ꢀH.; Chui, S. S.ꢀY.; Muccini, M.; Ning, J. Q.; Xu, S. J.;
Che, C.ꢀM. Angew. Chem., Int. Ed. 2008, 47, 9895–9899.
21. Po, C.; Tam, A. Y. Y.; Wong, K. M. C.; Yam, V. W.ꢀW. J. Am.
Chem. Soc. 2011, 133, 12136–12143.
2
2. Clever, G. H.; Kawamura, W.; Tashiro, S.; Shiro, M.; Shionoya,
ASSOCIATED CONTENT
M. Angew. Chem. Int. Ed., 2012, 51, 2606–2609.
23. Li, H.ꢀR.; Wu, L.ꢀZ.; Tung, C.ꢀH. J. Am. Chem. Soc. 2000, 122,
2446–2451.
24. Zhong, J.ꢀJ.; Meng, Q.ꢀY.; Wang, G.ꢀX.; Liu, Q.; Chen, B.;
Feng, K.; Tung, C.ꢀH.; Wu, L.ꢀZ. Chem. – Eur. J. 2013, 19, 6443–
Supporting Information. Synthesis, characterization, UVꢀVis,
1
H NMR and ITC titration data, photosensitization and photocataꢀ
lytic experiments, theoretical calculations and other materials.
This material is available free of charge via the Internet at
http://pubs.acs.org.
6
450.
5. Chow, P.ꢀK.; Ma, C.ꢀS.; To, W.ꢀP.; Tong, G. S. M.; Lai, S.ꢀL.;
Kui, S. C. F.; Kwok, W.ꢀM.; Che, C.ꢀM. Angew. Chem., Int. Ed. 2013,
2
AUTHOR INFORMATION
5
2, 11775–11779.
26. Meng, Q.ꢀY.; Lei, T.; Zhao, L.ꢀM.; Wu, C.ꢀJ.; Zhong, J.ꢀJ.; Gao,
X.ꢀW.; Tung, C.ꢀH.; Wu, L.ꢀZ. Org. Lett. 2014, 16, 5968–5971.
Corresponding Author
ACS Paragon Plus Environment