Oxygen Containing Reactions

Question 1

Nucleophile

Answer 1

Donates e- , lewis base, low electronegativity
RhH2C > RHN- > RO-
ex. -OH and -NH to attack carbonyl

Question 2

Leaving grp

Answer 2

Portion of molecule that leaves when carbonyl attacked

Good leaving groups: atoms in higher periods, gases, weak nucleophile/weak base

Question 3

Leaving Grp vs. Nucleophilicity

Answer 3

Leaving grp quality ————————————>

CH3- NH2- OR- OH- NH3 RCOO- H2O

Question 4

Alcohols

Answer 4

Name ends in -ol, name takes precedence unless carbonyl present, increases BP

Question 5

Rxns of Alcohols

Answer 5

As nucleophiles: (O donates e-)
As acids: (strongest) methyl> 1° > 2° >3° (weakest)
As leaving grp: Nucleophilic Substitution, -OH as nucleophile (ex. Tosylates and Mesylates for -OH protection)

Question 6

Alcohol -> Alkyl halide

Answer 6

CH3-CH-OH + H-Cl ->Cl- + CH3-CH-OH2+ ->Cl-CH2-CH3 + H20
O donates e- and take H from H-Cl
H2O leaves and Cl- takes its place

Question 7

Synthesis of Toslate and Mesylate

Answer 7

H-OR acts as nucleophile and causes Cl- to leave to become H-Cl

Question 8

Ether Rxns

Answer 8

Common solvent (relatively non-reactive), participates in substitution rxn or cleavage if a reactant

Question 9

Cleavage of Ether

Answer 9

R-O-R’ + H-Br -> R-OH + R-Br

Question 10

Nitrogen Rxns

Answer 10

Better nucleophile/worse leaving grp than O

Question 11

Nitrogen as Nucleophile

Answer 11

Lone pair e- attacks + charge
Nucleophilic Additon: Amine + Aldehyde/ketone
Nucleophilic substitution: Amine + carboxylic acid

Question 12

Nitrogen as Base

Answer 12

N takes on 4th bond becoming + charged

Ammonia/amines donate e- (acts as base)

Question 13

Electrophiles and Rxns

Answer 13

Most have carbonyls, planar chemistry aids in decreasing steric hindrance, C with δ+
w/ leaving group: nucleophilic substitution rxn (acyl chlorides, esters, amides)
w/o leaving group: nucleophilic addition rxn (ketones, aldehydes)

Question 14

Reactivity of Carbonyls

Answer 14

Least -> Amide - Carboxylic acid - Acid Anhdride/Ester - Ketone/Aldehyde - Acid Halide -> Most reactive

Question 15

Carboxylic Acid Rxns

Answer 15

Via Substitution rxns (either acts as acid and gives up H or has H20 as leaving group)
Carb. acids w/ 4 or fewer C are soluble in H20 (10+ not)

Question 16

Common Carboxylic Acid Derivatives

Answer 16

O
|| Carboxylic Acid
R-C-OH

 O
  ||                      Formic Acid  H-C-OH

     O
      ||                  Acetic Acid  3HC-C-OH

 O
 ||                      Benzoic Acid  Ar-C-OH

Question 17

Reactiity of Carboxylic Acid Derivatives

Answer 17

Least -> Amide - Ester - Carb. Acid - Anhydride - Acid Halide -> Most

Question 18

Esterification

Answer 18

Carboxylic acid + Alcohol -> H+ -> Ester + H20

Alcohol acts as nucleophile

Question 19

Transesterification

Answer 19

Ester + Alcohol -> H+ -> New Ester + New Alcohol

Question 20

Lactone Formation

Answer 20

Intramolecular esterification

Question 21

Ketone/Aldehyde Rxns

Answer 21

Via addition rxns
Very reactive because -H or -C don’t donate e- density
1. Nucleophile attacks carbonyl carbon
2.Carbon releases pi-bond e- to O
Acidic Conditions: O e- take H+ from acid, then Nuc attacks
Basic Condiions: Nuc attacks, O e- take H+ from H20

Question 22

Keto-enol tautomers

Answer 22

H hops to neighbor C, =O protonated
H O H OH H
| || | | |
R-C-C-C-H -> R-C=C-C-H
| | | |
H H H H

Question 23

Kinetic Enolate

Answer 23

Ketone in basic conditions, less substituted double bond, kinetically favored, less stable product

Question 24

Thermodynamic Enolate

Answer 24

Ketone in basic conditions, more substituted double bond, increases AE, more stable product

Question 25

Imine

Answer 25

Original amine has 0-1 R groups, C=N

Question 26

Enamine

Answer 26

Original amine has 2 R groups, C=C

Question 27

Grignard Synthesis of Alcohol

Answer 27

R-MgX + R-C=O -> R-3-C-O - + MgX -> R-3-C-OH + XMgOH

Question 28

Reduction Synthesis of Alcohol

Answer 28

H- + Ketone -> R-2-CH-O - -> R-2-CH-OH

Question 29

Oxidation

Answer 29

Increases bonds to O, loss of C-H bonds, decrease e- density

Question 30

Reduction

Answer 30

Increases bonds to H or R, decreases bonds to O, increase e- density

Question 31

Common Oxidizing Agents

Answer 31

K2Cr2O7 - 1° alcohol or aldehyde -> Carb. Acid K2MnO4 - 1° alcohol or aldehyde -> Carb. Acid H2CrO4 -1° alcohol or aldehyde -> Carb. Acid O2 PCC - 1° alcohol -> aldehyde; 2° alcohol -> ketone

Question 32

Common Reducing Agents

Answer 32

LiAlH4: Carb. Acid or aldehyde -> 1° Alcohol NaBH4: Aldehyde -> 1° Alcohol, Ketone -> 2° Alcohol H2 + Pressure

Question 33

Decarboxylation

Answer 33

Carb. Acid -> CO2 (g), exothermic, hard to do

Question 34

Aldol Condensation

Answer 34

Carbonyl + Carbonyl

Question 35

Carbohydrates

Answer 35

C chain w/ alcohol on each carbon except for 1 w/ aldehyde or ketone (aldose/ketose)

Question 36

Carbohydrate Classification: Linear and Cyclic

Answer 36

D: highest -OH in Fischer projection on right L: highest -OH in Fischer projection on left α: -OH points opposite side of methoxy grp while cyclic β: -OH points same side as methoxy grp while cyclic 5 member ring=furanose; 6 member ring=pyranose

Question 37

Di/polysaccharide fromation

Answer 37

Via dehydration (acetal formation)

Question 38

Common disaccharides

Answer 38

Sucrose: Glucose + Fructose, 1,2' linkage Maltose: Glucose + Glucose, α-1,4' linkage Lactose: Glucose + Lactose, β-1,4' linkage Cellulose: Chain of glucose, β-1,4' linkage Amylose: Chain of glucose, α-1,4 linkage Amylopectin: branched glucose chain, α-1,4' linkage w/ α-1,6' branching Glycogen: Branched glucose chain, α-1,4' linkage w/ α-1,6' branching

Question 39

Amino Acids

Answer 39

Contain amine and carboxylic acid ``` O=C-OH | H-C-R | NH2 ```

Question 40

Gabriel Synth

Answer 40

Amino acids synth de novo

Question 41

Strecher Synth

Answer 41

Amino acid from aldehyde + potassium cyanide + ammonium chloride

Question 42

Fatty Acids and Triglycerides

Answer 42

even numbered carbon chains w/ carboxylic acid at one end + glycerol + 3 fatty acid tails

Question 43

Lipogenesis

Answer 43

Fatty acids added on to glycerol to make triglyceride

Question 44

Lipolysis/Saponification

Answer 44

Removal of fatty acids from glycerol

Question 45

Saturated vs Unsaturated fatty acids

Answer 45

Saturated: no double bonds Unsaturated: contains 1+ double bonds, decreased MP

Question 46

Nucleic Acids

Answer 46

P=O behaves like C=O | -OH on one nucleic acid creates anhydride with phosphate group of another (phosphodiester bond)

Question 47

Formation of Phosphodiester bond

Answer 47

Nucleophilic substitution rxn | -OH on nucleic acid attacks P of the other prod H20

Question 48

Hydrolysis of Phosphodiester bond

Answer 48

H2O added and -O attacks P releasing e- back to O of neighboring phosphate