Tolman electronic parameter

<h2 id="other-ligand-electronic-parameters">Other ligand electronic parameters</h2>
<p>Several other scales have been proposed for the ranking of the donor properties of ligands.  The HEP scale ranks ligands on the basis of the 13C NMR shift of a reference ligand.<a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a>  Lever's electronic parameter ranking is related to the Ru(II/III) couple.<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a> Another scale evaluated ligands on the basis of the redox couples of [Cr(CO)5L]0/+.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a>
</p><p>In a treatment akin to the TEP analysis, the donor properties of <a href="/facts/N-heterocyclic_carbene/g4U9YPae">N-heterocyclic carbene</a> (NHC) ligands have been ranked according to IR data recorded on cis-[RhCl(NHC)(CO)2] complexes.<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a><a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a>
</p>

<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/Metal_carbonyl/KzJBcMzU">Metal carbonyl</a></li>
<li><a href="/facts/Tolman_cone_angle/Ie0bdRpR">Tolman cone angle</a></li></ul>

<h2 id="further-reading">Further reading</h2>
<ul><li>Tonner, Ralf; Frenking, Gernot (2009). "Tolman's Electronic Parameters for Divalent Carbon(0) Compounds". <i><a href="/facts/Organometallics/HR04qXU7">Organometallics</a></i>. 28 (13): 3901–3905. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fom900206w">10.1021/om900206w</a>.</li>
<li>Gusev, Dmitry G. (2009). "Electronic and Steric Parameters of 76 N-Heterocyclic Carbenes in Ni(CO)3(NHC)". <i><a href="/facts/Organometallics/HR04qXU7">Organometallics</a></i>. 28 (22): 6458–6461. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1021%2Fom900654g">10.1021/om900654g</a>.</li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>Robert H. Crabtree (2005). "Carbonyls, Phosphine Complexes, and Ligand Substitution Reactions". The Organometallic Chemistry of the Transition Metals. pp. 87–124. doi:10.1002/0471718769.ch4. ISBN 9780471718765. <a href="9780471718765" target="_blank">9780471718765</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>Tolman, C. A. (1977). "Steric effects of phosphorus ligands in organometallic chemistry and homogeneous catalysis". Chem. Rev. 77 (3): 313–348. doi:10.1021/cr60307a002. <a href="/wiki/Chem._Rev." target="_blank">/wiki/Chem._Rev.</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>Tolman, C. A. (1977). "Steric effects of phosphorus ligands in organometallic chemistry and homogeneous catalysis". Chem. Rev. 77 (3): 313–348. doi:10.1021/cr60307a002. <a href="/wiki/Chem._Rev." target="_blank">/wiki/Chem._Rev.</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
<li id="fn:4"><p>Teng, Qiaoqiao; Huynh, Han Vinh (2017). "A Unified Ligand Electronic Parameter Based on C NMR Spectroscopy of N-Heterocyclic Carbene Complexes". Dalton Transactions. 46 (3): 614–627. doi:10.1039/C6DT04222H. PMID 27924321. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li>
<li id="fn:5"><p>Lever, A. B. P. (1990). "Electrochemical parametrization of metal complex redox potentials, using the ruthenium(III)/Ruthenium(II) couple to generate a ligand electrochemical series". Inorganic Chemistry. 29 (6): 1271–1285. doi:10.1021/ic00331a030. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li>
<li id="fn:6"><p>Chatt, Joseph; Kan, C. T.; Leigh, G. Jeffery; Pickett, Christopher J.; Stanley, David R. (1980). "Transition-metal binding sites and ligand parameters". Journal of the Chemical Society, Dalton Transactions (10): 2032. doi:10.1039/DT9800002032. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li>
<li id="fn:7"><p>Nonnenmacher, Michael; Buck, Dominik M; Kunz, Doris (23 August 2016). "Experimental and theoretical investigations on the high-electron donor character of pyrido-annelated N-heterocyclic carbenes". Beilstein Journal of Organic Chemistry. 12: 1884–1896. doi:10.3762/bjoc.12.178. PMC 5082490. PMID 27829895. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5082490" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5082490</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li>
<li id="fn:8"><p>Huynh, Han Vinh (30 March 2018). "Electronic Properties of N-Heterocyclic Carbenes and Their Experimental Determination". Chemical Reviews. 118 (19): 9457–9492. doi:10.1021/acs.chemrev.8b00067. PMID 29601194. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li>
</ol>

Tolman electronic parameter open-in-new

Tolman electronic parameter