Analyzing Organic Reactions

Question 1

Lewis acid

Answer 1

electron acceptor in the formation of a covalent bond; vacant p orbital or are positively charged

Question 2

Lewis base

Answer 2

electron donor in the formation of a covalent bond; lone pair of electrons that can be donated and are often negative

Question 3

coordinate covalent bonds

Answer 3

formed when lewis acid and bases bond

Question 4

Bronsted-lowry acid

Answer 4

can donate a proton

Question 5

Bronsted-Lowry base

Answer 5

can accept a proton

Question 6

amphoteric

Answer 6

can act as both a BL acid and base

Question 7

acid dissociation constant Ka

Answer 7

measures the strength of an acid in solution

Question 8

Ka calculation

Answer 8

[H+][A-]/[HA]

Question 9

pKa calculation

Answer 9

-logKa

Question 10

pKa relationships

Answer 10

acid molecules have smaller pKa; basic molecules have larger pKa

Question 11

acidic functional groups

Answer 11

alcohols, aldehydes, ketons, carboxylic acids and most carboxylic acid derivatives

Question 12

basic functional groups

Answer 12

amines and amides

Question 13

nucleophiles

Answer 13

have either lone pairs or pi bonds that can form new bonds to electrophiles

Question 14

nucleophilic characteristics

Answer 14

charge: nucleophilicity increases with increasing electron density
electronegativity: nucleophilicity decreases as electronegativity increases
steric hindrance: bulkier molecules are less nucleophilic
solvent: protic solvents can hinder nucleophilicity

Question 15

solvent effects

Answer 15

polar protic solvents: nucleophilicity decreases down periodic table
polar aprotic solvents: nucleophilicty increases up the periodic table

Question 16

halogen nucleophilicity

Answer 16

in polar protic solvents: I- > Br- > Cl- > F-

In aprotic solvent: F- > Cl- > Br- > I-

Question 17

electrophiles

Answer 17

positive charge or positively polarized atom

Question 18

leaving groups

Answer 18

molecular fragments that retain the electrons after heterolysis

Question 19

heterolytic reaction

Answer 19

essential the opposite of coordinate covalent bond formation

Question 20

nucleophilic substitution reaction

Answer 20

nucleophile bonds with a substrate carbon and a leaving group leaves (SN1 and SN2)

Question 21

SN1 reactions

Answer 21

step one: leaving group leaves; rate limiting
step two: nucleophile attacks carbocation

the more substituted the cation, the mores table
rate depends only on substrate k[R-L]
creates racemic mixture

Question 22

SN2 reaction

Answer 22

• one step, the nucleophile attacks the compound at the same time the leaving group leaves
• concerted reaction
• backside attack
• nucleophile must be strong and no steric hindrance present
• rate depends on substrate and nucleophile
• inversion of configuration
• stereospecific reaction

Question 23

stereospecific reaction

Answer 23

configuration of reactant determines configuration of the product

Question 24

oxidation state

Answer 24

indication of the hypothetical charge an atom would have if all bonds were completely ionic

Question 25

oxidation

Answer 25

loss of electrons; increasing number of bonds to oxygen

Question 26

reduction

Answer 26

gain of electrons; increasing number of bonds to hydrogen

Question 27

oxidizing agent

Answer 27

element or compound in an oxidation-reduction reaction that accepts an electron from another species

Question 28

chemoselectivity

Answer 28

preferential reaction of one functional group in the presence of another functional group