Chapter 2: Alkyls, Aryls And Alcohol

Question 1

Addition/Elimination reactions

Answer 1

1. Addition: functional group is added
   1a. In order for a functional group to be added, there needs to be a double or triple bond
2. Elimination: functional group is removed
   2a. A hydrogen bond gets removed as well which can create alkanes or alkynes

Question 2

Substitution reactions

Answer 2

1. Occurs when one functional group substitutes for another
   1a. SN1: 2 steps, rate is dependant on first step (RDS)…can cause a racemic mixture is the electrophilic carbon is chiral in the product, 3>2>1 more likely to do SN1
   1b. SN2: creates inversion of configuration, doesn’t occur in 3
2. Nucleophile donates electrons to electrophile which causes a leaving group to leave

Question 3

Nucleophilicity

Answer 3

1. Defined by the rate of attack on a electrophilic carbon atom
   1a. Negative charges, polarizability, not bulky, and small EN all increase nucleophilicity

Question 4

Leaving groups

Answer 4

1. Good ones: weakly basic, electron withdrawing, stable and polarizable

Question 5

REDOX in Ochem

Answer 5

1. Oxidation: when molecular formula loses H2, or adds O, O2 or X2 (X=halogen)
2. Reduction: when molecular formula adds H2 or if it loses O, O2, or X2

Question 6

Radicals

Answer 6

1. Unpaired electrons
2. Toxic

Question 7

Names of specific alkyl groups

Answer 7

1. Methyl
2. Ethyl
3. Propyl
4. Butyl
5. Pentyl
6. Hexyl
7. Septyl

Question 8

Types of carbons in an alkane

Answer 8

1. Primary: 3 H, 1R (least stable other than methyl)
2. Secondary: 2H, 2R
3. Tertiary: 1H, 3R (most stable)
4. Quaternary: 4R

Question 9

Boiling points of alkanes

Answer 9

1. Heavier alkanes have higher boiling/melting points
2. Branched alkanes have lower boiling but higher melting points

Question 10

Axial vs equatorial hydrogens

Answer 10

1. Axial=crowd=less stable

Question 11

Halogenation reaction

Answer 11

1. When alkanes react with halogen radicals (F, CL, BR)

Question 12

Combustion reaction

Answer 12

1. When alkanes + oxygen = energy (heat) + water + co2

Question 13

Synthesis of Alkene

Answer 13

1. Via elimination reaction: when a functional group is eliminated to form a double bond

Question 14

Electrophilic addition

Answer 14

1. Markoxnikov rule: hydrogen is added to least substituted carbon of double bond

Question 15

Hydroxybenzene

Answer 15

1. Benzene + phenols

Question 16

Priority of functional groups

Answer 16

1. Most priority: carboxylic acid: -oic acid
2. Acid anhydride: -oic anhydride
3. Ester: -oate
4. Amide: -amide
5. Nitrile: -nitrile
6. Aldehyde: -al
7. Ketone: -one
8. Alcohol: -ol
9. Amine: -amine
10. Alkene: -ene
11. Alkyne: -yne
12. Alkane: -ane
13. Ether: -ether

Question 17

Physical properties of alcohols

Answer 17

1. Very high boiling points bc they can hydrogen bond, more soluble in water

Question 18

Synthesis of alcohols

Answer 18

1. Usually via SN2 reaction (substitute the alkyl halide)