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Dalton Transactions
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ARTICLE
Journal Name
Acknowledgements
DOI: 10.1039/D0DT01221A
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ARS thanks support from CONACYT Basic Science Project
53679. HSM thanks support from DGAPA IN110419 Project.
.014
.012
MeOH
water
2
CILP thanks a postdoctoral grant from SEP-PRODEP (México).
RAF gratefully acknowledges generous support by the National
Science Foundation (CHE-1565741).
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0
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[
additive] (M)
1
Figure 7.
acenaphthylene by 6 mM SmI
donors.
Rate comparison of the reduction of 2 mM
2
using MeOH and water as proton
Although the SmI
2
-MeOH combination provides a useful reducing
-H
This is likely a consequence of the decrease
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Conclusions
Herein we examined the similarities and differences using
methanol as a proton donor vs. water for SmI . The steric
2
interaction between methanol molecules in the first
solvation shell lead to a much smaller Sm-coordination
number of 5 as compared to 8.5 found when water is used
as solvent. The present results demonstrate that the
1
1
3
2
addition of methanol to SmI results in a reagent system that
3
reduces substrates through a sequential mechanism at low
concentrations of the proton donor. Methanol does not
coordinate as strongly to Sm(II) as water and as a
consequence, weakening of the O-H bond of methanol
bound to Sm(II) is diminished at low concentrations
precluding reduction through PCET. The increase in the rate
of substrate reduction at high concentrations of MeOH (1M)
demonstrates that a change in mechanism occurs when
coordination commences leading to a rate limiting PT or
PCET. We are currently examining a range of proton donors
to examine more fully the relationship between
coordination to Sm(II) and the mechanism of substrate
reduction.
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Conflicts of interest
There are no conflicts to declare.
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A. Ramírez-Solís, C. O. Bartulovich, T. V Chciuk, J.
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| J. Name., 2012, 00, 1-3
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