In chemistry, regioselectivity is the preference of one direction of chemical bond making or breaking over all other possible directions. It can often apply to which of many possible position a reagent will affect, such as which proton a strong base will abstract from an organic molecule, or when along a substituted benzene ring another substituent will add.

Regioselectivity in ring-closure reactions is governed by the Baldwin's rules.

External links

• Regioselectivity & Stereoselectivity

organic chemistry

اختيار اتجاه | Régiosélectivité