enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. SN2 reaction - Wikipedia

    en.wikipedia.org/wiki/SN2_reaction

    In the S N 1 reaction the nucleophile attacks after the rate-limiting step is over, whereas in S N 2 the nucleophile forces off the leaving group in the limiting step. In other words, the rate of S N 1 reactions depend only on the concentration of the substrate while the S N 2 reaction rate depends on the concentration of both the substrate and ...

  3. Nucleophilic substitution - Wikipedia

    en.wikipedia.org/wiki/Nucleophilic_substitution

    The rate equation for this reaction would be Rate=k[Sub][Nuc]. For a S N 2 reaction, an aprotic solvent is best, such as acetone, DMF, or DMSO. Aprotic solvents do not add protons (H + ions) into solution; if protons were present in S N 2 reactions, they would react with the nucleophile and severely limit the reaction rate.

  4. Solvent effects - Wikipedia

    en.wikipedia.org/wiki/Solvent_effects

    The rate equation for S N 2 reactions are bimolecular being first order in Nucleophile and first order in Reagent. ... Solvent effects on SN1 and SN2 reactions.

  5. Nucleophilic aromatic substitution - Wikipedia

    en.wikipedia.org/wiki/Nucleophilic_aromatic...

    A 2019 review argues that such 'concerted S N Ar' reactions are more prevalent than previously assumed. [3] Aryl halides cannot undergo the classic 'backside' S N 2 reaction. The carbon-halogen bond is in the plane of the ring because the carbon atom has a trigonal planar geometry. Backside attack is blocked and this reaction is therefore not ...

  6. Concerted reaction - Wikipedia

    en.wikipedia.org/wiki/Concerted_reaction

    The rate of the S N 2 reaction is second order overall due to the reaction being bimolecular (i.e. there are two molecular species involved in the rate-determining step). The reaction does not have any intermediate steps, only a transition state. This means that all the bond making and bond breaking takes place in a single step.

  7. Hammett equation - Wikipedia

    en.wikipedia.org/wiki/Hammett_equation

    The plot of the Hammett equation is typically seen as being linear, with either a positive or negative slope correlating to the value of rho. However, nonlinearity emerges in the Hammett plot when a substituent affects the rate of reaction or changes the rate-determining step or reaction mechanism of the reaction. For the reason of the former ...

  8. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    Using the Eyring equation, there is a straightforward relationship between ΔG ‡, first-order rate constants, and reaction half-life at a given temperature. At 298 K, a reaction with Δ G ‡ = 23 kcal/mol has a rate constant of k ≈ 8.4 × 10 −5 s −1 and a half life of t 1/2 ≈ 2.3 hours, figures that are often rounded to k ~ 10 −4 s ...

  9. Hammond's postulate - Wikipedia

    en.wikipedia.org/wiki/Hammond's_postulate

    Bimolecular nucleophilic substitution (SN2) reactions are concerted reactions where both the nucleophile and substrate are involved in the rate limiting step. Since this reaction is concerted, the reaction occurs in one step, where the bonds are broken, while new bonds are formed. [12] Therefore, to interpret this reaction, it is important to ...