what is vinylic carbon?
Dear Student,
Any carbon atom, which is attached to a carbon, which is linked with another carbon atom via double bond is called vinylic carbon.
On a carbon skeleton, sp2-hybridized carbons or positions are often called vinylic.
For example: In the given compound, carbon at number 3 is known as vinylic carbon, because it is bonded to double bonded carbon atom.
1 2 3
CH2=CH-CH3
Hope it helps!