Chapter 6 Notecards

an organic halide in which the halogen atom is bonded to an alkene carbon

an organic halide in which the halogen atom is bonded to an alkyl carbon

an organic halide in which the halogen atom is attached to an aromatic ring, such as a benzene ring.

a reaction whose rate-determining step involves to initially separate species.

the reaction where bond forming bond breaking occur simultaneously (in concert) through a single transition state.

elimination reaction that results in the loss of HX from adjacent carbons of the substrate the formation of a pi bond

a unimolecular elimination in which, in a slow, rate-determining step, a leaving group departs from the substrate to form a carbocation. The carbocation then in a fast step loses a proton with the resulting formation of a pi bond.

a bimolecular 1, 2 elimination in which, in a single step, a base removes a proton and a leaving group departs from the substrate, resulting in the formation of a pi bond

a reaction that results in the loss of two groups from the substrate and the formation of a pi bond. The most common elimination is a 1,2 elimination or elimination, in which the two groups are lost from adjacent atoms.

a reaction that proceeds with a positive free-energy change

a reaction that proceeds with a negative free-energy change

the difference in free energy between the transition state and the reactants

a plot of free-energy changes that take place during a reaction versus the reaction coordinate. It displays free-energy changes as a function of changes in bond orders and distances as reactants proceed to the transition state to become products.

a process that converts one functional group into another.

a postulate stating that the structure and geometry of the transition state of a given step will surely greater resemblance to the reactants or products of that step depending on which is closer to the transition state and energy. This means that the transition state of an endothermic step will resemble the products of that step more than the reactants, whereas the transition state of an exothermic step will resemble the reactants of that step one in the products.

electron delocalization (via orbital overlap) from a failed bonding orbital to an adjacent unfilled orbital. This generally has a stabilizing effect.

a transient species that exists between reactants and products in a state corresponding to a local energy minimum on a potential energy diagram.

At a tetrahedral atom, the process whereby one group is replaced by another bonded opportunity degree opposite to the original group. The other groups at the tetrahedral atom “turn inside out” (shift) in the same way that an umbrella “turns inside out.” When he chirality center undergoes configuration inversion, it’s (R, S) designation may switch, depending on the relative Cahn-Ingold-Prelog priorities of the groups before and after the reaction.

a term that refers to rates of reactions

a substituent that departs from the substrate in a nucleophilic substitution reaction

the number of species involved in a single step of a reaction (usually the rate-determining step).

a Lewis base, an electron pair donor that seeks a positive center in a molecule.

a reaction initiated by nucleophile (in neutral or negative species with an unshared electron pair) in which the nucleophile reacts with a substrate to replace a substituent (called the leaving group) that departs with and unshared electron pair.

the relative reactivity of a nucleophile in an SN2 reaction as measured by relative rates of reaction.

an organic halide in which the halogen atom is bonded to a benzene ring. A phenyl halide is a specific type of aryl halide.

a polar solvent that does not have a hydrogen atom attached to an electronegative element these solvents do not hydrogen bond with a Lewis base (e.g., a nucleophile).

a polar solvent that has at least one hydrogen atom bonded to an electronegative element. These hydrogen atoms of the solvent can form hydrogen bonds with a Lewis base (e.g., a nucleophile).

the susceptibility of the electron cloud of an uncharged molecule to distortion by the influence of electrical charge.

a reaction that transforms an optically active compound into racemic form a set to proceed with racemization. Racemization takes place whenever a reaction causes chiral molecules to be converted to an achiral intermediate.

if a reaction takes place in a series of steps, and at the first step is intrinsically slower than all of the others, than the rate of the overall reaction will be the same as (will be determined by) the rate of this slow step.

the abscissa in a potential energy diagram that represents the progress of the reaction. It represents the changes in bond orders and bond distances that must take place as reactants are converted to products.

literally, substitution nucleophilic unimolecular. A multistep nucleophilic substitution in which the leaving group departs in a unimolecular step before the attack of the nucleophile. The rate equation is first order in substrate but zero order in the attacking nucleophile.

literally, substitution nucleophilic bimolecular. A bimolecular nucleophilic substitution reaction that takes place in a single step. In nucleophile ataxic carbon bearing a leaving group from the backside, causing an inversion of configuration at this carbon and displacement of the leaving group.

an effect on relative rates of reaction caused by the solvent. For example, the use of a polar solvent will increase the rate of reaction of an alkyl halide and an SN1 reaction

literally, cleavage by the solvent. A nucleophilic substitution reaction in which the nucleophile is a molecule of the solvent.

chemical studies that take into account the spatial aspects of molecules

an effect on relative reaction rates cause by the space-filling properties of those parts of a molecule attached at or near the reacting site.

an effect on relative reaction rates cause when the spatial arrangement of atoms or groups at or near the reacting site hinders or retards a reaction

the molecule or ion that undergoes reaction

a state on a potential energy diagram corresponding to an energy maximum (i.e., characterized by having higher potential energy than immediately adjacent states). The term transition state is also used to refer to the species that occurs at the state of maximum potential energy; another term used for this species is the activated complex.

a reaction whose rate-determining step involves only one species.