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The term alcohol originally referred to the primary alcohol ethanol (ethyl alcohol), which is used as a drug and is the main alcohol present in alcoholic drinks. The suffix -ol appears in the International Union of Pure and Applied Chemistry (IUPAC) chemical name of all substances where the hydroxyl group is the functional group with the ...
Darzens halogenation is the chemical synthesis of alkyl halides from alcohols via the treatment upon reflux of a large excess of thionyl chloride or thionyl bromide (SOX 2) in the presence of a small amount of a nitrogen base, such as a tertiary amine or pyridine or its corresponding hydrochloride or hydrobromide salt.
The general mechanism for primary alkyl halides is shown in the figure below. [8] Mechanism of Friedel–Crafts alkylation. For primary (and possibly secondary) alkyl halides, a carbocation-like complex with the Lewis acid, [R (+)---(X---MX n) (–)] is more likely to be involved, rather than a free carbocation.
Alkyl groups that contain one ring have the formula −C n H 2n−1, e.g. cyclopropyl and cyclohexyl. The formula of alkyl radicals are the same as alkyl groups, except the free valence "−" is replaced by the dot "•" and adding "radical" to the name of the alkyl group (e.g. methyl radical •CH 3).
Phenoxides are close relatives of the alkoxides, in which the alkyl group is replaced by a phenyl group. Phenol is more acidic than a typical alcohol; thus, phenoxides are correspondingly less basic and less nucleophilic than alkoxides. They are, however, often easier to handle and yield derivatives that are more crystalline than those of the ...
Nucleophilic displacement of alkyl halides by alkoxides. R–ONa + R′–X → R–O–R′ + NaX. This reaction, the Williamson ether synthesis, involves treatment of a parent alcohol with a strong base to form the alkoxide, followed by addition of an appropriate aliphatic compound bearing a suitable leaving group (R–X). Although popular in ...
In principle, alkyltin halides can be formed from direct insertion of the metal into the carbon-halogen bond. However, such reactions are temperamental, typically requiring a very weak carbon-halogen bond (e.g. an alkyl iodide or an allyl halide) or crown-complexed alkali metal salt catalyst. Lewis acids or an ionic solvent may also promote the ...
Industrially, most alkylations are typically conducted using alcohols, not alkyl halides. Alcohols are less expensive than alkyl halides and their alkylation does not produce salts, the disposal of which can be problematic. Key to the alkylation of alcohols is the use of catalysts that render the hydroxyl group a good leaving group.