Question

Can someone please explain to me how is this less substituted? Please explain in detail. Thanks!!

Remember, you're looking for the less substituted group, so "b" is correct.... 1) ВН, 2) Н,О, ОН- 3) Н,О b a CH3 CH3 он н н он less substituted, anti-markovnikov

Answer 1

Less substituted means, carbon which bonded with less number of carbon. You just see in product (a) , the carbon bonded with -OH group is bonded with three carbon hence it is more substituted. While in (b) the carbon bonded with -OH group is attached only two carbon ,so it is less substituted.

Conclusion:- less substituted carbon is bonded with less number of carbon or we can say bonded with more number of hydrogen.