addition reaction
a reaction in which two atoms or ions react w/ a double bond, forming a compound w/ the two new groups bonded to the carbons of the original double bond
reactive intermediate
a high-energy species, formed between two successive reaction steps, that lies in an energy minimum between the two TSs.
rate-determining step
the step in a multistep reaction sequence that crosses the highest energy barrier
bond dissociation enthalpy
the amount of energy required to break a bond into two radicals in the gas phase at 25 degrees celsius
regioselective reaction
an addition or substitution reaction in which one of two or more possible products is formed in preference to all others that might be formed.
Markovnikov's rule
in the addition of HX, H2O, or ROH to an alkene, H adds to the carbon of the double bond having the greater number of Hs.
nucleophile
an yspecies that can donate a pair of electrons to form a a new covalent bond; alternatively, a Lewis base
electrophile
any species that can accept a pair of electrons to form a new covalent bond; alternatively, a Lewis acid
electrophilic additions
electrophile starts the addition to the alkene; is an addition reactionwhere, in a chemical compound, a ? bond is broken and two new ? bonds are formed. electrophile starts the addition of the alkene
inductive effect
the polarization of the electron density of a covalent bond resulting from the EN of a nearby atom
hyperconjugation
interaction of electrons in a sigma-bonding orbital with the vacant 2p orbital of an adjacent positively charged carbon
hydration
the addition of water
oxonium ion
an ion in which oxygen bears a positive charge
rearrangement
a change in connectivity of the atoms in a product compared w/ the connectivity of the same atoms in the starting material
1, 2 shift
a type of rearrangement in which an atom or group of atoms with its bonding electrons moves from one atom to an adjacent electron-deficient atom
stereoselective reaction
a reaction in which one stereoisomer is formed in preference to all others. A stereoselective reaction may be enantioselective or diastereoslective, as the case may be
anti stereoselectivity
the addition of atoms or groups of atoms to opposite faces of a C-C double bond
halohydrin
a compound containing a halogen atom and a hydroxyl group on adjacent carbons; those containing Br and OH are bromohydrins, and those containing Cl and OH are chlorohydrins
oxymercuration-reduction
a method for converting an alkene to an alcohol. The alkene is treated with mercury (II) acetate followed by reduction with sodium borohydride
hydroboration-oxidation
a method for converting an alkene to an alcohol. The alkene is treated with borane (BH3) to give a trialkylborane which is then oxidized w/ alkaline hydrogen peroxide to give the alcohol
hydroboration
addition of borane, (BH3), to an alkene, to form a trialkylborane
syn stereoselective
the addition of atoms or groups of atoms to the same face of a C-C double bond
oxidation
loss of electrons; alternatively, either the loss of hydrogens, the gain of oxygens, or both
reduction
the gain of electrons, alternatively, either the gain of hydrogen, loss of oxygens, or both
glycol
a compound with hydroxyl (-OH) groups on adjacent carbons
catalytic reduction/catalytic hydrogenation
conversion of an alkene to an alkane involves reduction by hydrogen in the presence of a catalyst
stereospecific reaction
a special type of stereoselective reaction in which the stereochemistry of the product is dependent on the stereochemistry of the starting material
entantioselective reaction
a reaction that produces one enantiomer in preference to the other
steps in electrophillic addition of a hydrogen halide to an alkene
steps in acid-catalyzed hydration
Le Chatelier's principle
States that if a stress is applied to a system at equilibrium, the system shifts in the direction that relieves the stress.
exergonic
the type of reaction that proceeds with a net release of free energy; because the chemical mixture loses free energy, Gibbs free energy is negative; it is a spontaneous reaction
endergonic
the type of reaction that absorbs free energy from surroundings; because energy is stored in molecules, Gibbs free energy is positive; the reaction is nonspontaneous
hydroboration
Addition of water to alkenes giving the non-markovnikov product. This reaction involves the addition of a B-H bond of boron, BH3, to an alkene to give an organoborane intermediate, RBH2. Oxidation of the organoborane by reaction with basic hydrogen peroxide, H2O2, then gives an alcohol.
hydroboration oxidation
a method for converting an alkene to an alcohol. The alkene is treated with borane (BH3) to give a trialkylborane which is then oxidized w/ alkaline hydrogen peroxide to give the alcohol
name the following compound
Hydrogenation is the process of?
Adding hydrogen molecules to an alkene.
The most stable alkene is?
Tetrasubstitut
organoborane
oxidation of an organoborane
Syn addition refers to the process where?
One atom adds to each carbon atom in a double bond from the same side of the double bond.
An electrophilic addition is?
An addition to an alkene initiated by an electrophilic attack.
vicinal dihalides
when 2 halogens substituents are attached to adjacent carbon atoms from halogenated alkenes
halogen addition is normally sterically syn or anti?
ANTI (opposite sides)
bromonium ion
A three-membered ring containging a positively charged bromine atom; an intermediate formed in the addition of bromine to an alkene.
electrophillic addition of bromine to ethylene
vicinal halohydrins
compounds that have a halogen and a hydroxyl group on adjacent carbons
peroxides cause reactions to proceed
opposite to Markovnikov's rule
peroxide effect
reversal of regioselectivity observed in the addition of hydrogen bromide to alkenes brought about by the presence of peroxides in the reaction mixture
electrophillic addition of a hydrogn halide to an alkene
acid catalyzed hydration
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