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<title>Arene substitution pattern</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Arene substitution pattern</span></span>

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<p><b><a href="Aromatic_compound" title="Aromatic compound">Arene</a> substitution patterns</b> are part of <a href="Organic_chemistry" title="Organic chemistry">organic chemistry</a> <a href="IUPAC_nomenclature_of_organic_chemistry" title="IUPAC nomenclature of organic chemistry">IUPAC nomenclature</a> and pinpoint the position of <a href="Substituent" title="Substituent">substituents</a> other than <a href="Hydrogen" title="Hydrogen">hydrogen</a> in relation to each other on an <a href="Aromatic_hydrocarbon" class="mw-redirect" title="Aromatic hydrocarbon">aromatic hydrocarbon</a>.

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<div class="mw-heading mw-heading2"><h2 id="Ortho,_meta,_and_para_substitution"><i>Ortho</i>, <i>meta</i>, and <i>para</i> substitution</h2></div>

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</style><div role="note" class="hatnote navigation-not-searchable">See also: <a href="Electrophilic_aromatic_substitution" title="Electrophilic aromatic substitution">Electrophilic aromatic substitution</a></div>

<ul><li>In <b><i>ortho</i>-substitution</b>, two substituents occupy positions next to each other, which may be numbered 1 and 2. In the diagram, these positions are marked R and <i>ortho</i>.</li>

<li>In <b><i>meta</i>-substitution</b>, the substituents occupy positions 1 and 3 (corresponding to R and <i>meta</i> in the diagram).</li>

<li>In <b><i>para</i>-substitution</b>, the substituents occupy the opposite ends (positions 1 and 4, corresponding to R and <i>para</i> in the diagram).</li></ul>

<p>The <a href="Toluidine" title="Toluidine">toluidines</a> serve as an example for these three types of substitution.

</p>

<div class="mw-heading mw-heading3"><h3 id="Synthesis">Synthesis</h3></div>

<p>Electron donating groups, for example <a href="Amino" class="mw-redirect" title="Amino">amino</a>, <a href="Hydroxyl" class="mw-redirect" title="Hydroxyl">hydroxyl</a>, <a href="Alkyl_group" title="Alkyl group">alkyl</a>, and <a href="Phenyl_group" title="Phenyl group">phenyl</a> groups tend to be <i>ortho</i>/<i>para</i>-directors, and electron withdrawing groups such as <a href="Nitro_compound" title="Nitro compound">nitro</a>, <a href="Nitrile" title="Nitrile">nitrile</a>, and <a href="Ketone" title="Ketone">ketone</a> groups, tend to be <i>meta</i>-directors.

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<div class="mw-heading mw-heading3"><h3 id="Properties">Properties</h3></div>

<p>Although the specifics vary depending on the compound, in simple disubstituted arenes, the three isomers tend to have rather similar boiling points. However, the <i>para</i> isomer usually has the highest melting point, and the lowest solubility in a given solvent, of the three isomers.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading3"><h3 id="Separation_of_ortho_and_para_isomers">Separation of <i>ortho</i> and <i>para</i> isomers</h3></div>

<p>Because electron donating groups are both <i>ortho</i> and <i>para</i> directors, separation of these isomers is a common problem in synthetic chemistry. Several methods exist in order to separate these isomers:

</p>

<ul><li><a href="Column_chromatography" title="Column chromatography">Column chromatography</a> will often separate these isomers, as the <i>ortho</i> is more <a href="Polarity_(chemistry)" class="mw-redirect" title="Polarity (chemistry)">polar</a> than the <i>para</i> in general.</li>

<li><a href="Recrystallization_(chemistry)" title="Recrystallization (chemistry)">Fractional crystallisation</a> can be used to obtain pure <i>para</i> product, relying on the principle that it is less soluble than the <i>ortho</i> and thus will crystallise first. Care must be taken to avoid <a href="Cocrystal" title="Cocrystal">cocrystallisation</a> of the <i>ortho</i> isomer.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></li>

<li>Many <a href="Nitro_compound" title="Nitro compound">nitro compounds</a>' <i>ortho</i> and <i>para</i> isomers have quite different <a href="Boiling_point" title="Boiling point">boiling points</a>. These isomers can often be separated by distillation. These separated isomers can be converted to <a href="Diazonium_salt" class="mw-redirect" title="Diazonium salt">diazonium salts</a> and used to prepare other pure <i>ortho</i> or <i>para</i> compounds.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup></li></ul>

<div class="mw-heading mw-heading2"><h2 id="Ipso,_meso,_and_peri_substitution"><i>Ipso</i>, <i>meso</i>, and <i>peri</i> substitution</h2></div>

<div class="gallerytext"><i>ipso</i>- substitution.</div>

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<div class="gallerytext"><i>meso</i>- substitution.</div>

</li>

<div class="gallerytext"><i>peri</i>- substitution.</div>

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<ul><li><b><i>Ipso</i>-substitution</b> describes two substituents sharing the same ring position in an intermediate compound in an <a href="Electrophilic_aromatic_substitution" title="Electrophilic aromatic substitution">electrophilic aromatic substitution</a>. <a href="Trimethylsilyl" class="mw-redirect" title="Trimethylsilyl">Trimethylsilyl</a>, <a href="Tert-Butyl" class="mw-redirect" title="Tert-Butyl"><i>tert</i>-butyl</a>, and <a href="Isopropyl" class="mw-redirect" title="Isopropyl">isopropyl</a> groups can form stable <a href="Carbocation" title="Carbocation">carbocations</a>, hence are <i>ipso</i> directing groups.</li>

<li><b><i>Meso</i>-substitution</b> refers to the substituents occupying a <a href="Benzyl" class="mw-redirect" title="Benzyl">benzylic</a> position. It is observed in compounds such as <a href="Calixarene" title="Calixarene">calixarenes</a> and <a href="Acridine" title="Acridine">acridines</a>.</li>

<li><b><i>Peri</i>-substitution</b> occurs in <a href="Naphthalene" title="Naphthalene">naphthalenes</a> for substituents at the 1 and 8 positions.</li></ul>

<div class="mw-heading mw-heading2"><h2 id="Cine_and_tele_substitution"><i>Cine</i> and <i>tele</i> substitution</h2></div>

<ul><li>In <b><i>cine</i>-substitution</b>, the entering group takes up a position adjacent to that occupied by the <a href="Leaving_group" title="Leaving group">leaving group</a>. For example, <i>cine</i>-substitution is observed in <a href="Aryne" title="Aryne">aryne</a> chemistry.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup></li>

<li><b><i>Tele</i>-substitution</b> occurs when the new position is more than one atom away on the ring.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></li></ul>

<div class="mw-heading mw-heading2"><h2 id="Etymology">Etymology</h2></div>

<p>The prefixes <i>ortho</i>, <i>meta</i>, and <i>para</i> are all derived from Greek, meaning <i>correct</i>, <i>following</i>, and <i>beside</i>, respectively. The relationship to the current meaning is perhaps not obvious. The <i>ortho</i> description was historically used to designate the original compound, and an isomer was often called the <i>meta</i> compound. For instance, the trivial names <a href="Phosphoric_acids_and_phosphates" title="Phosphoric acids and phosphates">orthophosphoric acid</a> and trimetaphosphoric acid have nothing to do with aromatics at all. Likewise, the description <i>para</i> was reserved for just closely related compounds. Thus <a href="J%C3%B6ns_Jakob_Berzelius" class="mw-redirect" title="Jöns Jakob Berzelius">Jöns Jakob Berzelius</a> originally called the <a href="Racemic" class="mw-redirect" title="Racemic">racemic</a> form of <a href="Tartaric_acid" title="Tartaric acid">tartaric acid</a> "paratartaric acid" (another obsolete term: <a href="Racemic_acid" title="Racemic acid">racemic acid</a>) in 1830. The use of the prefixes <i>ortho</i>, <i>meta</i> and <i>para</i> to distinguish isomers of disubstituted aromatic rings starts with <a href="Wilhelm_K%C3%B6rner" title="Wilhelm Körner">Wilhelm Körner</a> in 1867, although he applied the <i>ortho</i> prefix to a 1,4-isomer and the <i>meta</i> prefix to a 1,2-isomer.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> It was the German chemist <a href="Carl_Gr%C3%A4be" class="mw-redirect" title="Carl Gräbe">Karl Gräbe</a> who, in 1869, first used the prefixes <i>ortho</i>-, <i>meta</i>-, <i>para</i>- to denote specific relative locations of the substituents on a disubstituted aromatic ring (namely <a href="Naphthalene" title="Naphthalene">naphthalene</a>).<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> In 1870, the German chemist <a href="Viktor_Meyer" title="Viktor Meyer">Viktor Meyer</a> first applied Gräbe's nomenclature to <a href="Benzene" title="Benzene">benzene</a>.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> The current nomenclature was introduced by the <a href="Chemical_Society" title="Chemical Society">Chemical Society</a> in 1879.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading2"><h2 id="Examples">Examples</h2></div>

<p>Examples of the use of this nomenclature are given for <a href="Isomer" title="Isomer">isomers</a> of <a href="Cresol" title="Cresol">cresol</a>, C<sub>6</sub>H<sub>4</sub>(OH)(CH<sub>3</sub>):

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<div class="gallerytext"><a href="O-cresol" class="mw-redirect" title="O-cresol"><i>o</i>-cresol</a></div>

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<div class="gallerytext"><a href="M-cresol" class="mw-redirect" title="M-cresol"><i>m</i>-cresol</a></div>

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<div class="gallerytext"><a href="P-cresol" class="mw-redirect" title="P-cresol"><i>p</i>-cresol</a></div>

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<p>There are three arene substitution isomers of <a href="Dihydroxybenzene" class="mw-redirect" title="Dihydroxybenzene">dihydroxybenzene</a> (C<sub>6</sub>H<sub>4</sub>(OH)<sub>2</sub>) – the <i>ortho</i> isomer <a href="Catechol" title="Catechol">catechol</a>, the <i>meta</i> isomer <a href="Resorcinol" title="Resorcinol">resorcinol</a>, and the <i>para</i> isomer <a href="Hydroquinone" title="Hydroquinone">hydroquinone</a>:

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<div class="gallerytext"><a href="Catechol" title="Catechol">catechol</a></div>

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<div class="gallerytext"><a href="Resorcinol" title="Resorcinol">resorcinol</a></div>

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<div class="gallerytext"><a href="Hydroquinone" title="Hydroquinone">hydroquinone</a></div>

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<p>There are three arene substitution isomers of <a href="Benzenedicarboxylic_acid" title="Benzenedicarboxylic acid">benzenedicarboxylic acid</a> (C<sub>6</sub>H<sub>4</sub>(COOH)<sub>2</sub>) – the <i>ortho</i> isomer <a href="Phthalic_acid" title="Phthalic acid">phthalic acid</a>, the <i>meta</i> isomer <a href="Isophthalic_acid" title="Isophthalic acid">isophthalic acid</a>, and the <i>para</i> isomer <a href="Terephthalic_acid" title="Terephthalic acid">terephthalic acid</a>:

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<div class="gallerytext"><a href="Phthalic_acid" title="Phthalic acid">phthalic acid</a></div>

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<div class="gallerytext"><a href="Isophthalic_acid" title="Isophthalic acid">isophthalic acid</a></div>

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<div class="gallerytext"><a href="Terephthalic_acid" title="Terephthalic acid">terephthalic acid</a></div>

</li>

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<p>These terms can also be used in six-membered <a href="Heterocycle" class="mw-redirect" title="Heterocycle">heterocyclic</a> aromatic systems such as <a href="Pyridine" title="Pyridine">pyridine</a>, where the <a href="Nitrogen" title="Nitrogen">nitrogen</a> atom is considered one of the substituents. For example, <a href="Nicotinamide" title="Nicotinamide">nicotinamide</a> and <a href="Niacin_(nutrient)" class="mw-redirect" title="Niacin (nutrient)">niacin</a>, shown <i>meta</i> substitutions on a pyridine ring, while the <a href="Cation" class="mw-redirect" title="Cation">cation</a> of <a href="Pralidoxime" title="Pralidoxime">pralidoxime</a> is an <i>ortho</i> isomer.

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<div class="gallerytext">niacin</div>

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<div class="gallerytext"><a href="Nicotinamide" title="Nicotinamide">nicotinamide</a></div>

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<div class="gallerytext"><a href="Pralidoxime" title="Pralidoxime">pralidoxime</a></div>

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<ul><li><a href="Descriptor_(chemistry)" title="Descriptor (chemistry)">Descriptor (chemistry)</a></li>

<li><a href="Isomer" title="Isomer">Isomer</a></li>

<li><a href="Structural_isomerism" class="mw-redirect" title="Structural isomerism">Structural isomerism</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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<li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text">Morrison and Boyd, <i>Organic Chemistry</i>, Allyn and Bacon Inc, Boston, 1959. Ch.9, p. 250.</span>

</li>

<li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text">Morrison and Boyd, <i>Organic Chemistry</i>, Allyn and Bacon Inc, Boston, 1959. Ch. 10, p. 290.</span>

</li>

<li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text">Morrison and Boyd, <i>Organic Chemistry</i>, Allyn and Bacon Inc, Boston, 1959. Ch. 21, pp. 573-574.</span>

</li>

<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><a href="International_Union_of_Pure_and_Applied_Chemistry" title="International Union of Pure and Applied Chemistry">IUPAC</a>, <i><a href="IUPAC_books" class="mw-redirect" title="IUPAC books">Compendium of Chemical Terminology</a></i>, 5th ed. (the "Gold Book") (2025). Online version: (2006–) "<a rel="nofollow" class="external text" href="https://goldbook.iupac.org/terms/view/C01081.html">cine-substitution</a>". <style data-mw-deduplicate="TemplateStyles:r1238218222">

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</style><a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1351%2Fgoldbook.C01081">10.1351/goldbook.C01081</a></span>

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<li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><a href="International_Union_of_Pure_and_Applied_Chemistry" title="International Union of Pure and Applied Chemistry">IUPAC</a>, <i><a href="IUPAC_books" class="mw-redirect" title="IUPAC books">Compendium of Chemical Terminology</a></i>, 5th ed. (the "Gold Book") (2025). Online version: (2006–) "<a rel="nofollow" class="external text" href="https://goldbook.iupac.org/terms/view/T06256.html">tele-substitution</a>". <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1351%2Fgoldbook.T06256">10.1351/goldbook.T06256</a></span>

</li>

<li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text">Wilhelm Körner (1867) <a rel="nofollow" class="external text" href="https://www.biodiversitylibrary.org/item/28090#page/176/mode/1up">"Faits pour servir à la détermination du lieu chimique dans la série aromatique"</a> (Facts to be used in determining chemical location in the aromatic series), <i>Bulletins de l'Académie royale des sciences, des lettres et des beaux-arts de Belgique</i>, 2nd series, <b>24</b> : 166-185; see especially p. 169. From p. 169: <i>"On distingue facilement ces trois séries, dans lesquelles les dérivés bihydroxyliques ont leurs terms correspondants, par les préfixes </i>ortho<i>-, </i>para<i>- et </i>mêta<i>-."</i> (One easily distinguishes these three series – in which the dihydroxy derivatives have their corresponding terms – by the prefixes <i>ortho</i>-, <i>para</i>- and <i>meta</i>-.)</span>

</li>

<li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text">Hermann von Fehling, ed., <i>Neues Handwörterbuch der Chemie</i> [New concise dictionary of chemistry] (Braunschweig, Germany: Friedrich Vieweg und Sohn, 1874), vol. 1, <a rel="nofollow" class="external text" href="https://books.google.com/books?id=X_gfAQAAMAAJ&pg=PA1142">p. 1142.</a></span>

</li>

<li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text">Graebe (1869) <a rel="nofollow" class="external text" href="http://babel.hathitrust.org/cgi/pt?id=uva.x002457978;view=1up;seq=32">"Ueber die Constitution des Naphthalins"</a> (On the structure of naphthalene), <i>Annalen der Chemie und Pharmacie</i>, <b>149</b> : 20-28; see especially p. 26.</span>

</li>

<li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text">Victor Meyer (1870) <a rel="nofollow" class="external text" href="http://babel.hathitrust.org/cgi/pt?id=njp.32101044011672;view=1up;seq=649">"Untersuchungen über die Constitution der zweifach-substituirten Benzole"</a> (Investigations into the structure of di-substituted benzenes), <i>Annalen der Chemie und Pharmacie</i>, <b>156</b> : 265-301; see especially pp. 299-300.</span>

</li>

<li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text">William B. Jensen (March 2006) "The origins of the <i>ortho</i>-, <i>meta</i>-, and <i>para</i>- prefixes in chemical nomenclature," <i>Journal of Chemical Education</i>, <b>83</b> (3) : 356.</span>

</li>

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</style><div id="Stereochemistry181" style="font-size:114%;margin:0 4em"><a href="Stereochemistry" title="Stereochemistry">Stereochemistry</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Topics</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"><div class="hlist"><ul><li><a href="Chirality" title="Chirality">Chirality</a></li><li><a href="Racemic_mixture" title="Racemic mixture">Racemic mixture</a></li></ul></div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Descriptor_(Chemistry)" class="mw-redirect" title="Descriptor (Chemistry)">Configuration descriptors</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Cis%E2%80%93trans_isomerism" title="Cis–trans isomerism"><i>cis</i>–<i>trans</i> isomerism</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"><i>cis</i>-, <i>trans</i>-</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="E-Z_notation" class="mw-redirect" title="E-Z notation"><i>E</i>–<i>Z</i> notation</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">(<i>E</i>)-, (<i>Z</i>)-</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"><i>o</i>-, <i>m</i>-, <i>p</i>- (<i>ortho</i>, <i>meta</i>, <i>para</i>)</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Endo-exo_isomerism" class="mw-redirect" title="Endo-exo isomerism"><i>Endo</i>-<i>exo</i> isomerism</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"><i>endo</i>, <i>exo</i></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Syn_and_anti_addition" title="Syn and anti addition">Syn and anti addition</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"><i>syn</i>, <i>anti</i></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Descriptor_(Chemistry)" class="mw-redirect" title="Descriptor (Chemistry)">Three identical ligands</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"><i>fac</i>, <i>mer</i> (facies, meridional) [obsolete]</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Descriptor_(Chemistry)" class="mw-redirect" title="Descriptor (Chemistry)">In carbon skeletons</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"><i>n</i>, <i>iso</i>, <i>neo</i>, cyclo</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Secondary_(chemistry)" title="Secondary (chemistry)">Secondary</a> and <a href="Tertiary_(chemistry)" title="Tertiary (chemistry)">tertiary</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"><i>sec</i>-, <i>tert</i>-</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Spiro_compound" title="Spiro compound">Spiro compound</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">spiro</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Catenane" title="Catenane">Catenane</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"><i>catena</i></div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Absolute_configuration" title="Absolute configuration">Absolute configurations</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Cahn%E2%80%93Ingold%E2%80%93Prelog_priority_rules" title="Cahn–Ingold–Prelog priority rules">CIP (Cahn–Ingold–Prelog) priority rules</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">(<i>R</i>), (<i>S</i>)</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Descriptor_(Chemistry)" class="mw-redirect" title="Descriptor (Chemistry)">Pseudoasymmetric (pseudochiral) centers</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">(<i>r</i>), (<i>s</i>)</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Absolute_configuration#By_optical_rotation:_(+)-_and_(−)-_or_d-_and_l-" title="Absolute configuration">Optical rotation</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">(+)-, (−)- or <i>d-</i>, <i>l-</i></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Absolute_configuration#By_relative_configuration:_D-_and_L-" title="Absolute configuration">Relative configuration</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"><span class="smallcaps"><span style="font-variant: small-caps; text-transform: lowercase;">D</span></span>-, <span class="smallcaps"><span style="font-variant: small-caps; text-transform: lowercase;">L</span></span>-</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Coordination_complex#Optical_isomerism" title="Coordination complex">Octahedral propeller twist</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">Λ-, Δ-</div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div>Category:Stereochemistry</div></td></tr></tbody></table></div></div><div><div class="zim-footer">

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