Term
| A chiral object is superposable on its mirror image. |
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Definition
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Term
| Stereoisomers are one type of constitutional isomers. |
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Definition
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Term
| trans-1,2-dichloroethene has an enantiomeric relationship to the cis isomer. |
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Definition
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Term
| Disastereomers are stereoisomers which are not mirror images of each other. |
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Definition
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Term
| 2-Chloroheptane is achiral while 4-chloroheptane is not. |
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Definition
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Term
| Chiral molecules usually have a plane of symmetry. |
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Definition
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Term
| The (R) enantiomer of chiral compound usually rotates the plane of polarized light to the left. |
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Definition
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Term
| The nickel catalyzed hydrogenation of butanone produces (S)-2-butanol. |
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Definition
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Term
| The meso form of a molecule can be either dextrorotatory of levorotatory. |
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Definition
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Term
| trans-1,4-dimethlycyclohexane is achiral while the cis-isomer is chiral. |
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Definition
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Term
| 3-ethylcyclohexene is chiral. |
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Definition
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Term
| An equimolar mixture of enantiomers is called a racemic mixture. |
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Definition
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Term
| A plane of symmetry is defined as an imaginary plane that bisects a molecule in such a way that the two halves of the molecule are mirror images of each other. |
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Definition
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Term
| In the R,S system, a t-butyl substituent has a lower priority than an isobutyl substituent. |
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Definition
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Term
| In compounds whose stereoisomerism is due to chirality centers, the total number of stereoisomers will not exceed 2^n, where n is equal to the number of chirality centers. |
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Definition
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Term
| Diastereomers have different physical and chemical properties. |
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Definition
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Term
| Enantiomers can be easily separated by distillation or crystallization because their properties are different. |
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Definition
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Term
| 1,3-dibromoallene is chiral. |
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Definition
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Term
| cos-1,3-dichlorocyclobutane is chiral. |
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Definition
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Term
| Increasing the concentration of the nucleophilic species in an Sn1 reaction increases the rate of reaction. |
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Definition
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Term
| Carbocations are nucleophilic Lewis bases. |
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Definition
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Term
| The Sn2 reaction occurs by a back-side attack of the nucleophile on the chiral carbon bearing the leaving group. The results in retention of configuration at a chiral center. |
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Definition
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Term
| The difference in free energy between the reactants and the products is defined as the free energy of activation. |
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Definition
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Term
| The smaller the free energy of activation the slower the reaction. |
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Definition
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Term
| The overall rate in a multi-step reaction is controlled primarily by the slowest step in the reaction sequence. |
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Definition
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Term
| The first step in the Sn1 reaction of tert-butyl chloride is the homolytic cleavage of the carbon-chlorine bond. |
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Definition
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Term
| Carbocations have a trigonal planar geometry at the carbon bearing the positive charge. |
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Definition
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Term
| Carbon-hydrogen and carbon-carbon bonds located beta to a carbocationic center stabilize the cationic species by hyperconjugative electron delocalization. |
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Definition
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Term
| The Hammond-Leffler postulate states that the structure of a transition state resembles the stable species that is nearest it in free energy. |
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Definition
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Term
| Nucleophilicities are related to rates of reaction while basicities are related to equilibria. |
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Definition
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Term
| Dimethylsulfoxide and N,N-dimethylformamide are dipolar protic solvents. |
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Definition
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Term
| The Sn2 reaction is an example of a one-steop non-concerted reaction. |
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Definition
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Term
| The tert-butyl cation is less stable than the isopropyl cation. |
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Definition
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Term
| The reaction of tert-butyl chloride with methanol is an example of a methanolysis reaction. |
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Definition
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Term
| Secondary alkyl halides undergo Sn2 reactions more readily than primary alkyl halides. |
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Definition
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Term
| Neopentyl halides even though they are primary halides, are very unreactive in an Sn2 nucleophilic displacement due to steric effects. |
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Definition
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Term
| In polar, aprotic solvents such as dimethylsulfoxide, fluoride is a poorer nucleophile than iodide. |
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Definition
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Term
| In substitution reactions triflate is a poorer leaving group than p-toluenesulfonate. |
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Definition
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Term
| Vinyl chloride is a molecule where the chloride is attached to an sp hybridized carbon. |
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Definition
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Term
| A secondary carbocation is more stable than a vinyl carbocation. |
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Definition
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Term
| In an Sn2 reaction bromide is a better leaving group compared to chloride. |
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Definition
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Term
| In an Sn2 reaction bromide is a better nucleophile compared to iodide. |
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Definition
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Term
| tert-Butyl chloride undergoes an Sn1 process at a faster rate than sec-butyl chloride. |
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Definition
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Term
| Nucleophiles are species with at least one unshared electron pair. |
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Definition
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Term
| Nucleophiles are Lewis acids. |
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Definition
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Term
| In general, Sn2 reactions are characterized by 2nd-order kinetics. |
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Definition
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Term
| A concerted reaction is one in which there is a single energy barrier between the reactants and products. |
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Definition
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Term
| Sn2 reactions at a chiral center always occurs with inversion of configuration. |
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Definition
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Term
| The reaction of tert-butyl chloride with sodium methoxide in methanol leads to the formation of tert-butyl methyl ether. |
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Definition
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Term
| 1-Bromo[2.2.1]bicycloheptane, a tert halide, undergoes rapid ethanolysis. |
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Definition
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