"Stability of carbocation depends upon the electron releasing inductive effect of groups adjacent to positively charged carbon atom, involvement of neighbouring groups in hyperconjugation and resonance". Write structures of various carbocations that can be obtained from 2-methylbutane. Arrange the carbocations in order of increasing stability.

"Stability of carbocation depends upon the electron releasing inductiv

1.	"Stability of carbocation depends upon the electron releasing inductive effect of groups adjacent to positively charged carbon atom, involvement of neighbouring groups in hyperconjugation and resonance". Write structures of various carbocations that can be obtained from 2-methylbutane. Arrange the carbocations in order of increasing stability.
Answer» SOLUTION :2-Methylbutane has four DIFFERENT sets of equivalent hydrogen atoms marked as a, b, c and d. `{:(overset(a)(C)H_(3)-overset(b)(C)H-overset(c)(C)H_(2)-overset(d)(C)H_(3)),("\|"),(""underset(a)(C)H_(3)):}` Removal of one hydrogen form any of these equivalent sets of hydrogens gives four different carbocations I, II, III and IV as shown below : Now stability of carbocations decreases in the order : `3^(@) gt 2^(@) gt 1^(@)`. Since III being the `3^(@)` carbocation, it is the most STABLE. This is followed by carbocation (II) which is `2^(@)`. Out of the other two `1^(@)` carbocations, carbocation (IV) has an electron-donating `CH_(3)` group at `alpha`-carbon while carbocation (I) has a `CH_(3)` group at `beta`-carbon. Since +I effect decreases with distance, therefore, carbocation (IV) is more stable than carbocation (I). Thus, the overall stability of these four carbocations increases in the order : `I lt IV lt II lt III`.