Communication
Dalton Transactions
shorter than the Pd–Zn ones allowing the hydride to bridge
the Ni–Zn bond or by the fact that the Ni–H and Zn–H bonds
are of equivalent strengths whereas the Pd–H bond is stronger
than the Zn–H ones. Then, the formation of 4a and a putative
5a′ was considered. In the case of Ni, the reaction is computed
to be endothermic by 8.3 kcal mol−1, so the formation of 5a′ is
not favorable, which is consistent with experimental obser-
vations. In contrast, the formation of 4a is computed to be
both kinetically and thermodynamically favorable. The reac-
tion is a simple reductive elimination of H2 at the palladium
center. This also indicates that the formation of the Zn–Zn
and H–H bonds is not counterbalancing the loss of the brid-
ging hydrides whereas it is no longer the case when the
hydrides are not bridging.
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species Pd(PPh3)4 under mild conditions. Both structural para-
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by oxidative addition as a possible intermediate followed by
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application in multimetallic catalysis,2,29 which is under inves- 14 (a) H. Hao, C. Cui, H. W. Roesky, G. Bai, H.-G. Schmidt and
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Conflicts of interest
There are no conflicts to declare.
16 P. Xu, Y. Yao and X. Xu, Chem. – Eur. J., 2017, 23, 1263–
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Acknowledgements
Financial support from the National Natural Science 17 A.-K. Wiegand, A. Rit and J. Okuda, Coord. Chem. Rev.,
Foundation of China (Grant No. 21871204 and 21502132), the 2016, 314, 71–82.
1000-Youth Talents Plan, the Jiangsu Specially-Appointed 18 M. Tüchler, L. Gärtner, S. Fischer, A. D. Boese, F. Belaj and
Professor Plan, PAPD, and the Project of Scientific and
Technologic Infrastructure of Suzhou (SZS201708).
N. C. Mösch-Zanetti, Angew. Chem., Int. Ed., 2018, 57, 6906–
6909.
19 (a) W. Sattler and G. Parkin, J. Am. Chem. Soc., 2011, 133,
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M. S. P. Shaffer and C. K. Williams, Organometallics, 2014,
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Notes and references
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