Search results
Results from the WOW.Com Content Network
Vinyl cation are invoked as reactive intermediates in solvolysis of vinyl halides, [1] [2] as well as electrophilic addition to alkynes and allenes. [3] Note that unlike the allyl and benzyl carbocations (top left and right, respectively), the electron-deficient carbon of the vinyl carbocation (bottom) is double-bonded.
Carbocations were also found to be involved in the S N 1 reaction, the E1 reaction, and in rearrangement reactions such as the Whitmore 1,2 shift. The chemical establishment was reluctant to accept the notion of a carbocation and for a long time the Journal of the American Chemical Society refused articles that mentioned them.
This relationship is according to the equation ΔG = –RT ln K (Gibbs free energy). The rate equation for S N 2 reactions are bimolecular being first order in Nucleophile and first order in Reagent. The determining factor when both S N 2 and S N 1 reaction mechanisms are viable is the strength of the Nucleophile. Nuclephilicity and basicity ...
The tert-butyl cation is a relatively stable carbenium ion. [1]A carbenium ion is a positive ion with the structure RR′R″C +, that is, a chemical species with carbon atom having three covalent bonds, and it bears a +1 formal charge.
Pages in category "Carbocations" ... Vinyl cation This page was last edited on 31 December 2018, at 21:47 (UTC). Text is available under the Creative ...
For example, polyhydroxymethylene films obtained by alkaline hydrolysis of polyvinylene carbonate films via sodium methoxide in methanol are crystalline and exhibit high tensile strengths. [10] Analogous to cellulose, polyhydroxymethylene can be dissolved in hot sodium hydroxide solution and converted by crosslinking into a highly swellable ...
Though a relatively stable tertiary carbocation, tert-butyl cation is a high-energy species that is present only at very low concentration and cannot be directly observed under normal conditions. Thus, the SSA can be applied to this species:
The addition will proceed through the low energy chair transition state, rather than the relatively high energy twist-boat. An example of this type of reaction can be seen below. The example also highlights how the stereoelectronic effect exerted by an electronegative substituent flips the lowest energy conformation and leads to opposite ...