If in both resonance forms the formal charge of 1 is on a secondary carbon it also is a secondary allylic carbocation.
A secondary vinylic carbocation is.
The vinyl cation is a carbocation with the positive charge on an alkene carbon.
Its empirical formula is c 2 h 3 more generally a vinylic cation is any disubstituted trivalent carbon where the carbon bearing the positive charge is part of a double bond and is sp hybridized in the chemical literature substituted vinylic cations are often referred to as vinyl cations and understood to.
The general formula for vinyl group is r ch ch 2 in which both carbon atoms are bonded with double bond and r is attached at vinylic position.
Secondary carbocations will require more energy than tertiary and primary carbocations will require the most energy.
In the first mechanism step the alkyne is protonated by hydronium ion a strong acid to produce a resonance stabilized secondary vinylic carbocation shown in red.
The carbocation bonded to three alkanes tertiary carbocation is the most stable and thus the correct answer.
Acid catalyzed hydration of phenyl acetylene a terminal alkyne involves a vinylic carbocation intermediate.
The more substituted a carbocation is the more stable it is.
This carbocation is also a benzylic carbocation.
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If in the more stable of the two resonance forms of an allylic carbocation the formal charge of 1 is on a secondary carbon the allylic carbocation is called a secondary 2 allylic carbocation.
Since both carbon atoms form a double covalent bond so both are sp 2 hybridized.