Addition of electrophilic reagents to olefins

Reagent Control of regioselectivity Stereospecificity in aliphatic systems Product Ref. 

Addition via bridged intermediates is characterized by anti stereochemistry, since the nucleophile opens the ring by backside attack  

Electronic control of ring-opening— nucleophilic attack at more positive carbon 

Steric control of ring-opening—nucleophilic attack at less substituted carbon 

In cyclic olefins, addition occurs by diaxial addition  

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