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Hydroalkoxylation is a chemical reaction that combines alcohols with alkenes or alkynes. The process affords ethers. The reaction converts alkenes to dialkyl or aryl-alkyl ethers: R'OH + RCH=CH 2 → R'OCH(R)-CH 3. Similarly, alkynes are converted to vinyl ethers: R'OH + RC≡CH → R'OC(R)=CH 2. As shown, the reaction follows the Markovnikov rule.
The Williamson ether synthesis is an organic reaction, forming an ether from an organohalide and a deprotonated alcohol . This reaction was developed by Alexander Williamson in 1850. [2] Typically it involves the reaction of an alkoxide ion with a primary alkyl halide via an S N 2 reaction.
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.
In organic chemistry, the Menshutkin reaction converts a tertiary amine into a quaternary ammonium salt by reaction with an alkyl halide. Similar reactions occur when tertiary phosphines are treated with alkyl halides. Menshutkin-reaction. The reaction is the method of choice for the preparation of quaternary ammonium salts. [1]
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.
Also, the best results for this test are observed in tertiary alcohols, as they form the respective alkyl halides fastest due to higher stability of the intermediate tertiary carbocation. The test was reported in 1930 and became a standard method in qualitative organic chemistry. [ 2 ]
The sulfonium oxidations can be categorized into two groups: The methods discovered earliest rely on activated alcohols like alkyl tosylates (Kornblum oxidation) [2] or alkyl chloroformates (from reaction of alcohols with phosgene: Barton-Kornblum) [3] that react as electrophiles when treated with DMSO, liberating an oxygenated leaving group (e.g. OTs−).
Primary alkyl halides react with aqueous NaOH or KOH to give alcohols in nucleophilic aliphatic substitution. Secondary and especially tertiary alkyl halides will give the elimination (alkene) product instead. Grignard reagents react with carbonyl groups to give secondary and tertiary alcohols.