HC: Alkenes (w/ Alkynes)

true or false: majority of drugs are alkenes

true or false: alkynes are rare in drugs

olefins

other name for alkenes

acetylenes

other name for alkynes

oil forming

olefins meaning

double bond

fxn group of alkene

unsaturated or saturated?

alkenes are unsaturated

degree of unsaturation

number of rings and/ or multiple bonds on the molecule

thermal cracking

breaking large hydrocarbons into smaller ones using heat

(alkene + steam + 900° + few seconds —→ alkene)

characteristics of alkene

1. nonpolar

2. liquid at room temperature

3. less dense than water

4. aliphatic

5. unsaturated

due to multiple HC

reason why alkenes are non-polar

polymerization

repeated molecule units

alkynes

contains at least 1 triple bond

CnH2n-2

general formula for alkynes that has only 1 triple bond

triple bond

fxn group of alkynes

-yne

suffix for alkynes in iupac naming

-ene

suffix for alkenes in iupac naming

trans-2-butene

cis-2-butene

E-entgegen

heavy and opposite sides

Z-zusammen

heavy and same side

E,Z naming using Cahn-Ingold-Prelog system

System of naming based on the 4 substituents around the double bond

Alkene stability

depends on how many alkyl groups (carbon groups) are attached to the double bond.

tetrasubstituted > trisubstituted > disubstituted > monosubstituted

stability of alkenes in decreasing order

true or false: more alkyl groups = more stable alkene

tetrasubstitued

most stable alkene; 4 alkyl groups around C=C

monosubstitued

least stable alkene; 1 alkyl group around C=C

1. Electrophilic addition

2. Markovnikov’s Rule

reaction of alkenes

Electrophilic Addition

double or triple bond is broken, and two new single bonds are formed. It occurs when an electron-rich bond (like a \(C=C\) double bond) is attacked by an electrophile (an electron-loving, positively charged or neutral species)

Markovnikov’s rule

helps predict where atoms attach in unsymmetrical alkenes; “the rich gets richer”; carbon with more H gets more H.; the double bond breaks

1. Hydrochlorination

2. Hydration

3. Hydrogenation

4. Bromination

4 reactions of alkenes

Hydrochlorination

addition of HCl to an alkene; product: haloalkane/ alkylhalide; follows Markovnikov’s rule

Hydration

addition of H2O to an alkene w/ catalyst like H2SO4;

product is an alcohol (-OH);

follows Markovnikov’s rule

Bromination

addition of Bromine (Br2) to an alkene;

product: dibromoalkane;

adds Br across both carbons equally;

does not follow Markovnikov’s rule

Hydrogenation

addition of H2 (hydroen) to an alkene with Ni, Pt, or Pt catalyst

Product: Alkane

Gives a fully saturated alkane

= reduction

1. Hydrochlorination

2. Hydration

rxns that follows Markovnikov’s rule

1. Bromination

2. Hydrogenation

does not follow Markovnikov’s rule

hydrochlorination

hydration

bromination

hydrogenation