Alcohols, Phenols and Ethers
Alcohols, Phenols and Ethers
Alcohols, Phenols and Ethers
R-OH
Functional group of an alcohol molecule ethanol ethyl alcohol
C2H5OH
propan-2-ol, 2-propanol, iso, isopro, isoprop, C3H7OH rubbing alcohol, or the abbreviation IPA isopropyl alcohol)
Chemistry 21A
cholesterol
The best source is probably Mentha arvensis, Corn Mint, whose oil is up to 85% (-)-menthol.
Glycerin, glycerine, propane-1,2,3-triol Bombykol The sex pheromone of the silk moth
A fatty alcohol with two double bonds, bombykol (tr-10,cis-12-hexadecadien-1-ol), was also shown to be excreted as a very strong attractive substance by the female of silk-worm (Bombyx mori).
The bombyx mori silk moth
Chemistry 21A
H O H
alcohol
H O H
phenol
O H
H O H
ether group
ether
R O H
R O R
O
phenol group
OH
H3C C H2 H2 C OH
-OH
hydroxyl group
propan-1-ol
R~
alkyl group
diphenyl ether
Chemistry 21A
ALCOHOLS, PHENOLS and ETHERS Nomenclature of Alcohols 1. Alcohols are named by finding the longest continues carbon chain and changing the ending to ol (e.g., methanol, ethanol, propanol, etc.). 2. With unsaturated alcohols, two endings are needed, one for the double or triple bond and one for the hydroxyl group. The ol suffix is last and takes precedence in the numbering. 3. If the hydroxyl group is directly attached to an aromatic ring, the compound is named as a phenol. 4. If the hydroxyl group occurs in a carboxylic acid, aldehyde, or ketone, it is named as a substituent (hydroxy) because the former functionalities have higher priority. 5. The common names for the alcohols are the alkane chain named as a substituent followed by the word alcohol (e.g., methyl alcohol, ethyl alcohol, etc.)
OH
H3C
H2 C
H2 C
OH
C H2 OH
H3C
OH
H3C
C H3C H CH3
propan-1-ol, 1-propanol,
propan-2-ol, 2-propanol,
C4H9OH alcohols
H2 C H2 C
OH
CH3 C OH H3C H C H2
H3C
C H2
OH
CH3 C H3C H C H2
OH
H2 C OH
HO
C H2
H2 H2 C H C OH C HO OH
trans-3-methylcyclohexanol
HO
OH
HO
H3C
OH
OH OH
1,2,3-propanetriol glycerin
1-methylcyclopentanol
Dr. Dragan Marinkovic
Chemistry 21A
OH
OH
HO
phenol
OH Cl
3-methylphenol
4-ethylphenol
OH
Cl
alcohol
Cl
2,4,6-trichlorophenol
Chemistry 21A
benzyl alcohol
Dr. Dragan Marinkovic
H3C
H2 C
C H2
H2 C
OH
CH3 C OH H3C H C H2
OH
CH3 C H3C H C H2
primary alcohol
H2 C OH
secondary alcohol
primary alcohol
tertiary alcohol
OH
H3C OH
HO
C H2
HO
OH
trans-3-methylcyclohexanol
1-methylcyclopentanol
Chemistry 21A
As a result, alcohols have boiling points that are much higher than alkanes with similar molecular weights. The boiling point of ethanol, for example, is 78.5C, whereas propane, with about the same molecular weight, boils at -42.1C.
The difference in boiling points between alkanes and alcohols with the same number of carbon atoms decreases when the total number of carbons increases (i.e. with the increase of hydrophobic character of alcohols).
CH3CH2OCH2CH3
CH3CH2CH2CH2OH
BP = 34.5C
d = 0.7138 g/mL insoluble in water
Chemistry 21A
BP = 117.2C
d = 0.8098 g/mL soluble in water
Dr. Dragan Marinkovic
CH3OH
CH3CH2OH CH3(CH2)2OH
OH
OH
methanol
ethanol propanol
infinitely soluble
infinitely soluble infinitely soluble
OH
CH3(CH2)3OH
CH3(CH2)4OH CH3(CH2)5OH CH3(CH2)6OH CH3(CH2)7OH CH3(CH2)9OH
butanol
pentanol hexanol heptanol octanol decanol
Chemistry 21A
9
2.7 0.6 0.18 0.054
OH
OH
insoluble in water
As the length of the alcohol increases, the effect of hydrogen bonding decreases and hydrophobic forces become dominant.
The difference in boiling points between alkanes and alcohols with thw same number of carbon atoms decreases when the total number of carbons increases (i.e. with the increase of hydrophobic character of alcohols).
Chemistry 21A
synthesis of ethers
H3C
H2 C C H2 OH
HO
C H2
H2 C
H2 C
C H2
C H2
H2 C
CH3
Chemistry 21A
Chemistry 21A
H3C
C H2
OH
oxydation
H3C H
O
oxydation
H3C
O OH
ethanol
acetaldehyde
acetic acid
Chemistry 21A
H3C H CH3 C
secondary alcohol
oxydation
H3C O
CH3
R R' R" OH
no reaction
oxydation
tertiary alcohol
H3C
CH3 OH CH3
oxydation
no reaction
Chemistry 21A
Pure 100% ethanol has an octane rating of 113. Adding 10% ethanol to gasoline raises the overall octane by 2 to 3 points. Lower BTU value than gasoline
C6H12O6
70 atm 300oC
H3C
C2H5OH + O2
CH3COOH + H2O
ethylene (ethene)
C H2
OH
For most of human history, acetic acid, in the form of vinegar, has been made by acetic acid bacteria of the genus Acetobacter.
Chemistry 21A Dr. Dragan Marinkovic
Chemistry 21A
ALCOHOLS, PHENOLS and ETHERS Methanol is produced naturally in the anaerobic metabolism of many varieties of bacteria
CO + 2H2
CH3OH
Drag racers and mud racers also use methanol as their primary fuel source.
Chemistry 21A Dr. Dragan Marinkovic
propan-2-ol, 2-propanol, iso, isopro, isoprop, C3H7OH rubbing alcohol, or the abbreviation IPA isopropyl alcohol)
Chemistry 21A
CH4 < NH3 < HCCH < ROH < H2O < phenols < H2CO3 < RCOOH < HF
OH + NaOH SA water insoluble OH + NaHCO3 NR phenol < H2CO3 SB WB water soluble ONa + H2O WA
Chemistry 21A
Joseph Lister, 1st Baron Lister, (1827 1912) was an English surgeon who promoted the idea of sterile surgery while working at the Glasgow Royal Infirmary. He successfully introduced carbolic acid (phenol) to sterilize surgical instruments and to clean wounds, which led to reduced post-operative infections and made surgery safer for patients.
Butylated hydroxytoluene (BHT), also known as butylhydroxytoluene, is a organic compound that is primarily used as an antioxidant food additive (E number E321) as well as in cosmetics, pharmaceuticals, jet fuels, rubber, petroleum products, and embalming fluid
4-Hexylresorcinol is a chemical compound with anaesthetic, antiseptic and antihelmintic properties. It can be used topically on small skin infections, or as an ingredient in throat lozenges.
Anthelmintics or antihelminthics are drugs that expel parasitic worms (helminths) from the body, by either stunning or killing them. They may also be called vermifuges (stunning) or vermicides (killing).
4-hexylbenzene-1,3-diol
Raspberry ketone is a natural phenolic compound that is the primary aroma compound of red raspberries. It is used in perfumery, in cosmetics, and as a food additive to impart a fruity odor.
Chemistry 21A Dr. Dragan Marinkovic
ALCOHOLS, PHENOLS and ETHERS PHENOLS are next-generation anti-oxidant found throughout nature in some of the healthiest foods. PHENOLS are the common health-giving link that ties together foods such as Red Wine, Green Tea, Dark Chocolate, and Super-Berries.
A polyphenol antioxidant is a type of antioxidant containing a polyphenolic substructure. In human health these compounds, numbering over 4000 distinct species, are thought to be instrumental in combating oxidative stress, a process associated with some neurodegenerative diseases and some cardiovascular diseases.
Dr. Dragan Marinkovic
R O R
O
Polyethylene glycol has a low toxicity and is used in a variety of products. It is the basis of a number of laxatives (such as Movicol and polyethylene glycol 3350, or MiraLax or GlycoLax). Polyethylene glycol (PEG) It is the basis of many skin creams, as cetomacrogol, and sexual lubricants, Anisole (methoxybenzene) An aryl ether and a major constituent of the essential oil of anise seed.
Dr. Dragan Marinkovic
diphenyl ether
Chemistry 21A
ALCOHOLS, PHENOLS and ETHERS Physical Properties: The polar nature of the C-O bond (due to the electronegativity difference of the atoms ) results in intermolecular dipole-dipole interactions. An ether cannot form hydrogen bonds with other ether molecules since there is no H to be donated (no -OH group) Ethers can be involved in H-bonding with systems able to donate H (e.g. water). The implications of these effects are: lower melting and boiling points compared to analogous alcohols solubility in aqueous media similar to analogous alcohols.
CH3CH2OCH2CH3
CH3CH2CH2CH2OH
BP = 34.5C
d = 0.7138 g/mL insoluble in water
Chemistry 21A
BP = 117.2C
d = 0.8098 g/mL soluble in water
Dr. Dragan Marinkovic
The absence of an -OH group in an ether also has important consequences for its chemical properties. Unlike alcohols, ethers are essentially inert to chemical reactions. They don't react with most oxidizing or reducing agents, and they are stable to most acids and bases, except at high temperatures. They are therefore frequently used as solvents for chemical reactions. However, ethers are generally extremely FLAMMABLE and tend, If exposed to air for longer periods of time, to form EXPLOSIVE PEROXIDES.
Chemistry 21A
A thiol is a compound that contains the functional group composed of a sulfur atom and a hydrogen atom (-SH). Being the sulfur analogue of an alcohol group (-OH), this functional group is referred to either as a thiol group or a sulfhydryl group. More traditionally, thiols are often referred to as mercaptans.
The preferred method (used by the IUPAC) is to add the suffix -thiol to the name of the alkane. The method is nearly identical to naming an alcohol. Example: CH3SH would be methanethiol. An older method, the word mercaptan replaces alcohol in the name of the equivalent alcohol compound. Example: CH3SH would be methyl mercaptan. (CH3OH would be methyl alcohol)
Chemistry 21A
ALCOHOLS, PHENOLS and ETHERS Many thiols are colorless liquids having an odor resembling that of garlic. The odor of thiols is often strong and repulsive, particularly for those of low molecular weight
Natural gas distributors began adding various forms of pungent thiols, originally ethanthiol, to natural gas, which is naturally odorless, after the deadly 1937 New London School explosion in New London, Texas. Most gas odorants utilized in the world contain mixtures H3C of mercaptans and sulfides, with t-butyl mercaptan as the main odor constituent.
CH3 SH CH3
Cysteine
(oxydation)
Chemistry 21A
Diallyl disulfide (4,5-dithia-1,7-octadiene) is an organosulfur compound, along with diallyl trisulfide and diallyl tetrasulfide it is one of the principal components of the distilled oil of garlic.
Chemistry 21A
ALCOHOLS, PHENOLS and ETHERS 2R-SH + (O) R-S-S-R + H2O 2CH3SH + (O) CH3-S-S-CH3 thiol disulfide 2CH3SH + Pb2+ CH3-S-Pb-S-CH3 + 2H+
Coenzyme A (CoA, CoASH, or HSCoA) is a coenzyme, notable for its role in the synthesis and oxidation of fatty acids, and the oxidation of pyruvate in the citric acid cycle.
Chemistry 21A Dr. Dragan Marinkovic
Chemistry 21A
Chemistry 21A