Alcohol general

The organic chemistry you need for the new MCAT is the organic you see in biochemistry. The hydroxyl group performs important roles in biochem as a nucleophile, a leaving group, or as a site of oxidation.

An alcohol is an organic compound with one or more hydroxyl groups bound to a saturated carbon atom. Reactions of alcohols are important for the new MCAT because alcohols appear everywhere in biochemistry. From basic carbohydrate chemistry to the reactions of the citric acid cycle to the mechanism of a serine protease, understanding the hydroxyl group is an essential foundation.

WikiPremed Resources



Reactions of Alcohols and Ethers Images
Image gallery for study with links to larger teaching JPEGs for classroom presentation

Question Drill for Alcohols
Conceptual Vocabulary Self-Test

Basic Terms Crossword Puzzle

Basic Puzzle Solution

Learning Goals

Proficiency 

Be able to picture the means by which acid catalysis activates the hydroxyl group as a leaving group, enabling alcohols to undergo SN1 Substitution or E1 Elimination.

Remember that Thionyl Chloride and Phosphorus Tribromide enable the transformation of an alcohol into an alkyl halide.

Be able to assign oxidation number to the hydroxyl carbon of an alcohol and be able to place alcohols within the redox sequence including aldehydes/ketones and carboxylic acids.

Understand the acid-base properties of alcohols and the significance within reaction chemistry, i.e. the use of alkoxide anion as a nucleophile.

Recall how ethers may be formed as well as characterize their reactivity.

Be capable of elucidating the nature of epoxides, their formation and basic reactivity.

Suggested Assignments

Review the basic terms for reactions of alcohols using the question server. Complete the fundamental terms crossword puzzle. Here is the solution to the puzzle.

Study the WikiPremed reaction mechanisms for alcohols.

Read pp. 83-85 in ExamKrackers Chemistry. Perform practice items 49-56 on pp. 87-88 (practice items for aldehydes & ketones, alcohols, and amines).

Review the web resources for reactions of alcohols.

Conceptual Vocabulary for Alcohols

Ether
Ether is the general name for a class of chemical compounds which contain a ether group - an oxygen atom connected to two alkyl or aryl groups.
Nucleophilic substitution
Nucleophilic substitution is a fundamental class of substitution reaction in which an electron rich nucleophile selectively bonds with or attacks the positive charge of a group or atom called the leaving group.
Dehydration reaction
A dehydration reaction is a chemical reaction that involves the loss of water from the reacting molecule.
Esterification
Esterification is the general name for a chemical reaction in which two chemicals, such as an alcohol and an acid, form an ester as the reaction product.
Alkoxide
An alkoxide is the conjugate base of an alcohol.
Fischer esterification
Fischer esterification is the process of forming an ester by refluxing a carboxylic acid and an alcohol in the presence of an acid catalyst.
Epoxide
An epoxide is a cyclic ether with only three ring atoms.
Williamson ether synthesis
The Williamson ether synthesis involves the reaction of an alkoxide ion with a primary alkyl halide via an SN2 reaction.
Thionyl chloride
Thionyl chloride is an inorganic compound often used in chlorination reactions in which sulfur is bound to an oxygen and two chlorine atoms.
Phosphorus tribromide
Phosphorus tribromide is widely used in the laboratory for the conversion of alcohols to alkyl bromides.
Transesterification
Transesterification is the process of exchanging the alkoxy group of an ester compound by another alcohol.
Jones oxidation
The Jones oxidation is a chemical reaction described as the chromic acid oxidation of primary and secondary alcohols to carboxylic acids and ketones, respectively.
Crown ether
Crown ethers are heterocyclic chemical compounds that, in their simplest form, are cyclic oligomers of ethylene oxide.
Swern oxidation
The Swern oxidation is a chemical reaction whereby a primary or secondary alcohol is oxidized to an aldehyde or ketone using oxalyl chloride, dimethyl sulfoxide (DMSO) and an organic base, such as triethylamine.
Guerbet reaction
The Guerbet reaction is an organic reaction converting a primary aliphatic alcohol into its beta-alkylated dimer alcohol with loss of one equivalent of water.
Chugaev elimination
The Chugaev elimination is a chemical reaction involving a xanthate intermediate that carries out the elimination of water from primary alcohols to produce terminal alkenes.