Chem 343 exam 2 Questions and Answers Fully Solved Graded A+
nucleophile - Answersspecies that donates electron pair to form a new bond
electrophile - Answersspecies that accepts electrons from a nucleophile
leaving group - Answersgroup that accepts electrons from the bond breaking
hyperconjugation - Answersinteraction (partial e- donation) between a sigma CH and p orbital that
stabilizes carbocations by electron delocalization
what does H2 need in order to react with alkenes - Answerscatalyst to activate new pathways, often
times metals
how does H2 add when reacting with an alkene - Answerssyn-only, both attach in one contact
what is an enantiomer - Answersall stereocenters have been reversed, they are non-superimposable
mirror images
do enantiomers have the same or different chemical and physical properties - Answersidentical chemical
and physical properties in achiral environments
what is a meso compound - Answersmolecules identical to its mirror image, contains plane of internal
symmetry
what is a diastereomer - Answersat least one, but not all stereocenters, are the same, they are NOT
mirror images
do mesocompounds have the same or different chemical and physical properties - Answersidentical
physical and chemical properties
do diastereomers have the same or different chemical and physical properties - AnswersDIFFERENT
chemical and physical properties in all environments
is oxymercuration anti or syn only - Answersanti-only, water can ONLY be opposite Hg (FIRST STEP)
is oxymercuration reduction anti or syn only - Answersthe reduction (workup) can scramble to anti and
syn attachments
What two reagents indicate that the reaction will be an oxidation - AnswersH2O2 (hydrogen peroxide)
and OH- (hydroxide)
What acts as a nucleophile and electrophile in a hydroboration reaction - AnswersBH2 is the electrophile
(positively charged) and H is the nucleophile (negatively charged)
Where does the OH group attach in hydroboration oxidation - Answersthe OH attaches to the least
substituted carbon
nucleophile - Answersspecies that donates electron pair to form a new bond
electrophile - Answersspecies that accepts electrons from a nucleophile
leaving group - Answersgroup that accepts electrons from the bond breaking
hyperconjugation - Answersinteraction (partial e- donation) between a sigma CH and p orbital that
stabilizes carbocations by electron delocalization
what does H2 need in order to react with alkenes - Answerscatalyst to activate new pathways, often
times metals
how does H2 add when reacting with an alkene - Answerssyn-only, both attach in one contact
what is an enantiomer - Answersall stereocenters have been reversed, they are non-superimposable
mirror images
do enantiomers have the same or different chemical and physical properties - Answersidentical chemical
and physical properties in achiral environments
what is a meso compound - Answersmolecules identical to its mirror image, contains plane of internal
symmetry
what is a diastereomer - Answersat least one, but not all stereocenters, are the same, they are NOT
mirror images
do mesocompounds have the same or different chemical and physical properties - Answersidentical
physical and chemical properties
do diastereomers have the same or different chemical and physical properties - AnswersDIFFERENT
chemical and physical properties in all environments
is oxymercuration anti or syn only - Answersanti-only, water can ONLY be opposite Hg (FIRST STEP)
is oxymercuration reduction anti or syn only - Answersthe reduction (workup) can scramble to anti and
syn attachments
What two reagents indicate that the reaction will be an oxidation - AnswersH2O2 (hydrogen peroxide)
and OH- (hydroxide)
What acts as a nucleophile and electrophile in a hydroboration reaction - AnswersBH2 is the electrophile
(positively charged) and H is the nucleophile (negatively charged)
Where does the OH group attach in hydroboration oxidation - Answersthe OH attaches to the least
substituted carbon
