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  2. Triphenylcarbethoxymethylenephosphorane - Wikipedia

    en.wikipedia.org/wiki/Triphenylcarbethoxym...

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  3. Wittig reagents - Wikipedia

    en.wikipedia.org/wiki/Wittig_reagents

    Wittig reagents are usually described as a combination of two resonance structures: Ph 3 P + CR 2 − ↔ Ph 3 P=CR 2. The former is called the ylide form and the latter is called the phosphorane form, which is the more familiar representation. Crystallographic characterization of methylenetriphenylphosphorane shows that the phosphorus atom is ...

  4. Methylenetriphenylphosphorane - Wikipedia

    en.wikipedia.org/wiki/Methylenetriphenylphosphorane

    2 Structure. 3 Uses. 4 Related reagents. ... The compound is usually described as a combination of two resonance structures: ... triphenylphosphorane;

  5. Carbomethoxymethylenetriphenylphosphorane - Wikipedia

    en.wikipedia.org/wiki/Carbomethoxymethylenetri...

    This article about an organic compound is a stub. You can help Wikipedia by expanding it.

  6. Clar's rule - Wikipedia

    en.wikipedia.org/wiki/Clar's_rule

    Clar's rule states that for a benzenoid polycyclic aromatic hydrocarbon (i.e. one with only hexagonal rings), the resonance structure with the largest number of disjoint aromatic π-sextets is the most important to characterize its chemical and physical properties. Such a resonance structure is called a Clar structure. In other words, a ...

  7. Resonance (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Resonance_(chemistry)

    Contributing structures of the carbonate ion. In chemistry, resonance, also called mesomerism, is a way of describing bonding in certain molecules or polyatomic ions by the combination of several contributing structures (or forms, [1] also variously known as resonance structures or canonical structures) into a resonance hybrid (or hybrid structure) in valence bond theory.

  8. Three-center four-electron bond - Wikipedia

    en.wikipedia.org/wiki/Three-center_four-electron...

    This bonding scheme is succinctly summarized by the following two resonance structures: I—I···I − ↔ I − ···I—I (where "—" represents a single bond and "···" represents a "dummy bond" with formal bond order 0 whose purpose is only to indicate connectivity), which when averaged reproduces the I—I bond order of 0.5 obtained ...

  9. Parikh–Doering oxidation - Wikipedia

    en.wikipedia.org/wiki/Parikh–Doering_oxidation

    The Parikh–Doering oxidation is an oxidation reaction that transforms primary and secondary alcohols into aldehydes and ketones, respectively. [1] The procedure uses dimethyl sulfoxide (DMSO) as the oxidant and the solvent, activated by the sulfur trioxide pyridine complex (SO 3 •C 5 H 5 N) in the presence of triethylamine or diisopropylethylamine as base.