General chemistry - more substituted carbon has weaker bond?

[Monkeymaniac]

TBR organic chemistry book has an example, a sp2 carbon has one single bond to CH3 and another single bond to CH(CH3)2. It just says that the bond with CH(CH3)2 is weaker because the C is more substituted. Is this because the methyls contribute electron densities, which destablize the bond? Thanks in advance.

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[loveoforganic]

The methyls give hyperconjugative and inductive stabilization of the formed radical.

 

[fastfingers]

could somebody simplify answer?

 

[golgiapparatus88]

Bonds are stronger when there are a lot of electrons shared between the two nuclei. If the electron density is spread out, you get weaker bonds.

 

[chemtopper]

Presence of two bulky methyl groups will increase the steric hindrance and interelectronic repulsion on the C atom and this can be the reason for slightly longer bondlength.Please take care if there are lots of electrons ,it doesnt mean that you can use them all in one bond.In a bond you can have only two electrons (maximum) and a lot of electrons around it will cause only problems to that bonded pair.