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6

The Wharton rearrangement presents an opportunity to convert one α,β-unsaturated ketone to its regioisomeric allylic alcohol. To this end Ohloff, et al.,1,2 explored the transformation of α-ionone 1 into α-damascone 2. Epoxide 3 was exposed to hydrazine in methanol to afford bicyclic allylic alcohol 4 (30%) and the uncyclized allylic ...

4

It isn't unstable at all. 1,2-diiodoethane is characterized with a melting point of 80–82 °C, and a mass spectrum with five major peaks. It even serves as the iodine source in some rare earth iodide syntheses. Read about it on Wikipedia.

4

I am not sure what back bonding you are referring to. It may be related to the outdated concept of silicon using its vacant, high-energy d orbitals in any meaningful way which is not actually the case. There is a second effect which consists of overlap of nitrogen’s p orbitals with the σ* orbitals of the $\ce{Si-H}$ bonds (which are silicon-centred ...

3

$\ce{H2A}$ and $\ce{A^2-}$ forms of a biprotic acid seldom coexist as major components, expecially if the acid is weak, unless $\mathrm{p}K_\mathrm{a1}$ and $\mathrm{p}K_\mathrm{a2}$ are similar. Instead, coexistence of major components $\ce{H2A / HA-}$ or $\ce{HA- / A^2-}$ occurs. $\ce{SO3^2-}$ starts to form in about neutral or alkalic solutions, while $\... 3 It does not make sense for the constant to be zero. The constant is usually expressed as follows: $$K_M = \frac{k_{\mathrm{reverse}} + k_{\mathrm{catalytic}}}{k_{\mathrm{forward}}}$$ Since the$k$values are strictly non-negative, the constant would only be zero if$k_{\mathrm{reverse}} = k_{\mathrm{catalytic}} = 0$. In theory,$k_{\mathrm{reverse}}$... 3 This is not a magical reaction. Yet, it is a two step reaction as depicted in diagram below: As @Waylander's comment elsewhere, benzyl chloride might have converted to benzyl alcohol before get oxidized to benzoic acid in acidic$\ce{KMnO4}$solution (the first step). This oxidation is well known (see here). The second step is heating (may be$\gt \pu{200 ^\...

2

Clear distinction has to be made between Arrhenius-equation and transition state theory. The formulas for TST can be derived, as opposed to Arrhenius equation, which by itself, is not based on a solid physical derivation. Basically any process can be modeled by an Arrhenius equation that has the formula: $$r \propto \exp{(-E_a/RT)}$$ Any molecular ...

1

This elimination is unfavorable because C--C bonds are generally quite stable. Decarboxylation would involve the formation of an unstable carbanion before proceeding to the elimination as you have outlined. (Note, this is more favorable under different functional group conditions, namely when a neighboring carbonyl can stabilize the carbanion through the ...

1

The key feature in the product that shows what is going on is the trans configuration of the two bromines. This is characteristic of the addition of elemental bromine via a brominium ion mechanism here. So where does the Br2 come from as we started with HBr? This is where the hydrogen peroxide comes in. It is well documented example here that hydrogen ...

1

Your reaction goes way back to 1930s when Ingold and coworkers have done pioneering work on nitration of aromatic compounds using nitric acid in organic solvents in place of sulfuric acid (vide infra). Let's see how this has been developed: Historical perspectives: The earliest recorded experiments on the kinetics of aromatic nitration has been performed ...

1

It should first be noted that the circle drawn derives from experimental results. If you were to mark specific oxygens, e.g. by introducing radioactive $\ce{^18O}$ in place of normal $\ce{^16O}$, you can predict whether and where the ester product will contain $\ce{^18O}$ or not and whether the water will contain $\ce{^18O}$ or not. \begin{align}\ce{R-CO-...

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