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  2. Arrow pushing - Wikipedia

    en.wikipedia.org/wiki/Arrow_pushing

    Arrow pushing or electron pushing is a technique used to describe the progression of organic chemistry reaction mechanisms. [1] It was first developed by Sir Robert Robinson.In using arrow pushing, "curved arrows" or "curly arrows" are drawn on the structural formulae of reactants in a chemical equation to show the reaction mechanism.

  3. Elimination reaction - Wikipedia

    en.wikipedia.org/wiki/Elimination_reaction

    Elimination reaction of cyclohexanol to cyclohexene with sulfuric acid and heat [1] An elimination reaction is a type of organic reaction in which two substituents are removed from a molecule in either a one- or two-step mechanism. [2] The one-step mechanism is known as the E2 reaction, and the two-step mechanism is known as the E1 reaction ...

  4. Hammond's postulate - Wikipedia

    en.wikipedia.org/wiki/Hammond's_postulate

    In an E2 mechanism, a base takes a proton near the leaving group, forcing the electrons down to make a double bond, and forcing off the leaving group-all in one concerted step. The rate law depends on the first order concentration of two reactants, making it a 2nd order (bimolecular) elimination reaction.

  5. Evelyn effect - Wikipedia

    en.wikipedia.org/wiki/Evelyn_effect

    The Evelyn effect is defined as the phenomena in which the product ratios in a chemical reaction change as the reaction proceeds. This phenomenon contradicts the fundamental principle in organic chemistry by reactions always go by the lowest energy pathway. The favored product should remain so throughout a reaction run at constant conditions.

  6. Reactivity series - Wikipedia

    en.wikipedia.org/wiki/Reactivity_series

    The order of reactivity, as shown by the vigour of the reaction with water or the speed at which the metal surface tarnishes in air, appears to be Cs > K > Na > Li > alkaline earth metals, i.e., alkali metals > alkaline earth metals, the same as the reverse order of the (gas-phase) ionization energies.

  7. Reaction mechanism - Wikipedia

    en.wikipedia.org/wiki/Reaction_mechanism

    An example of a simple chain reaction is the thermal decomposition of acetaldehyde (CH 3 CHO) to methane (CH 4) and carbon monoxide (CO). The experimental reaction order is 3/2, [4] which can be explained by a Rice-Herzfeld mechanism. [5] This reaction mechanism for acetaldehyde has 4 steps with rate equations for each step :

  8. Zaytsev's rule - Wikipedia

    en.wikipedia.org/wiki/Zaytsev's_rule

    In organic chemistry, Zaytsev's rule (or Zaitsev's rule, Saytzeff's rule, Saytzev's rule) is an empirical rule for predicting the favored alkene product(s) in elimination reactions. While at the University of Kazan , Russian chemist Alexander Zaytsev studied a variety of different elimination reactions and observed a general trend in the ...

  9. Woodward–Hoffmann rules - Wikipedia

    en.wikipedia.org/wiki/Woodward–Hoffmann_rules

    Thermolysis converts 1 to (E,E) geometric isomer 2, but 3 to (E,Z) isomer 4.. The Woodward–Hoffmann rules (or the pericyclic selection rules) [1] are a set of rules devised by Robert Burns Woodward and Roald Hoffmann to rationalize or predict certain aspects of the stereochemistry and activation energy of pericyclic reactions, an important class of reactions in organic chemistry.