Kaplan Organic Chemistry: Chapter 4 Analyzing Organic Reactions

Question 1

the more electronegative, the ___ the acidity

Answer 1

the HIGHER the acidity. e- density pulled away from H+, more likely to leave.

Question 2

the lower the bond strength, the ___ the acidit

Answer 2

the higher the acidity.

Question 3

periodic table trend for acidity

Answer 3

acidity increases going DOWN the periodic table.

Question 4

higher Ka = ___ acid.

higher pka = ____ acid

Answer 4

higher ka = STRONGER acid

higher pka = WEAKYER acid.

Question 5

formula for pka

Answer 5

pka= -log (Ka)

lower pka = stronger acid.

Question 6

functional groups that act as bass

Answer 6

amines, amides

Question 7

functional gorups that act as acids

Answer 7

aldehydes, ketones, carbox acids, CA derivatives (e/x anhydrides)

Question 8

is a nucleophilic atom acidic or basic

Answer 8

BASIC. remember, a base is an electron donor or a proteon acceptor. it WANTS positive charge– it is nucleophilic.

Question 9

the more electrons the more :

Answer 9

nucleophilic

Question 10

the more En, the ____ nucleophilic

Answer 10

LESS nucleophilic. It wants e- instead– its electrophilic

Question 11

nucleophilicity and steric hinderance

Answer 11

mulkier moleucles are LESS nucleophilic.

Question 12

nucleophilicity and solvents

Answer 12

protic solvents INHIBIT nucleophilicity by protonating the nucleophile or hydrogen bonding.

Question 13

in a protic solvent, rank the nucleophilicity of the halides

Answer 13

1. I-
2. Br -
3. Cl-
4. F- (least nucleophilic in a protic solvent)

F- is least nucleophilic because they are preoccupied with hydrogen bonding with the protic solvent itself.

Question 14

T/F: you can conduct a nucleophile reaction in hexane

Answer 14

FALSE. nucleiphiles are always polar, and often carry a charge. therefore, you need a POLAR solvent, whether protic or aprotic. you CANNOT carry out a substitution nucleophilic reaction in hexane. the nucleophile MUST be able to dissolve in the solvent.

Question 15

electrophiles are leis ___

Answer 15

acids. the more acidic, the more electrophilic. Lewis acids are electron acceptors.

Question 16

the weaker the base, the more stable in solution, which increases the ___ reactivity

Answer 16

electrophilic.

Question 17

the more positively charged, the ___ electrophilic

Answer 17

the more electrophilic.

Question 18

name the acidity (and thus, ELECTROPHILICITY) of carboxylic acid derivatives

Answer 18

1) anhydride
2) CA
3) ESTER
4) amide

Question 19

heterolytic reaction

Answer 19

when a bond is broken and BOTH electrons are given to ONE of the two products.

Question 20

weak bases, aka ______, are good leaving gorups

Answer 20

conjugate bases of strong acids. Ex/ I-, Cl-, Br- are good leaving groups.

Question 21

Sn1 reactions favors what type of carbon? What type of solvent/

Answer 21

Sn1 reactions favors SUBSTITUTED carbons and PROTIC solvents because it is a multi-step reactions and the carbocation can be stabilized by the solvent.

Question 22

Sn2 reactions favors what type of carbon? what type of solvent?

Answer 22

Sn2 ractions favors LEAST SUB carbons and APROTIC POLAR solvents because it is a single step reaction and the solvent cannot be interfering with the substrates by hydrogen bonding with them. therefore, they need a substrate that cannot Hbond.

Question 23

rate equation for SN2

Answer 23

rate = k (Nu)(RL)

Question 24

Primary alcohols can be oxidized to form ___,

Answer 24

aldehydes

Question 25

primary alcohol to aldehyde requires ___. Primary alcohol to CA requries ___

Answer 25

primary alcohol to aldehyde requires PCC. Primary alcohol to CA requries STRONGER OXIDIZERS (K2Cr2O7)

Question 26

secondary alcohols can be oxidized to form ____

Answer 26

ketones.

Question 27

an aldehyde can converted to a CA via

Answer 27

peroxide or stronger oxidizers.

Question 28

oxidation reactions increase the number of bonds to

Answer 28

oxygen

Question 29

reduction reactions increase the number of bonds to

Answer 29

hydrogen

Question 30

how can you break an alkene into an aldehyde and a ketone

Answer 30

ozonolysis. O3 paired with zinc.

Question 31

tertiary alcohols can undergo oxidation to ___

Answer 31

false. tertiary alcohols cannot undergo oxidation because all the bonds to carbon are being used up and cannot suport a double bond to oxygen.

Question 32

electronegativity and its relationship to being a good reducing agent

Answer 32

good reducing agnets are LOWER in En. wannts to get rid of electrons, wants to get oxidized. Na, Mg, Al, Zn are all good reducing agents- they want to lose e-.

Question 33

reduction of esters results in

Answer 33

a pair of alcohols

Question 34

reduction of aldehyde

Answer 34

primary alcohol

Question 35

reduction of ketone

Answer 35

secondary alcohol

Question 36

reduction of amide

Answer 36

amine

Question 37

why are alpha hydrogens more acidic in carbonyls than in regular CH bonds?

Answer 37

because they are resonance stabilized of the enol form.