In the addition of a protic acid HX to an asymmetric alkene, the acid hydrogen (H) becomes attached to the carbon with fewer alkyl substituents (more hydrogens), and the halide (X) group becomes attached to the carbon with more alkyl substituents.
Organic Chemistry
Field: Organic Chemistry
Sequence of Expressions
In the presence of peroxides, the addition of HBr to unsymmetrical alkenes occurs such that the H atom binds to the carbon atom with fewer hydrogen atoms (Kharasch effect).
In elimination reactions, the major product is the most substituted alkene (the most stable alkene).
In elimination reactions involving quaternary ammonium salts or sterically hindered bases, the less substituted alkene is favored.
Law
Bredt's Rule
A double bond cannot be placed at the bridgehead of a bridged ring system, unless the rings are large enough.
A planar, cyclic, conjugated molecule is aromatic if it has electrons.
Predicts the stereochemical outcome of pericyclic reactions based on the conservation of orbital symmetry.
A set of guidelines for ring closure reactions, classifying them as favored or disfavored based on the ring size, the hybridization of the breaking bond, and the endo/exo relationship.
In the reduction of cyclohexanones or epoxide ring openings, the nucleophile attacks to give the trans-diaxial product (Trans-diaxial effect).
The transition state of a reaction resembles the structure of the species (reactant or product) to which it is closer in energy.
For a reaction that has two products formed from two rapidly equilibrating conformers, the product ratio depends on the energy difference between the transition states, not the equilibrium constant between the conformers.