Titanocene-catalyzed alkylative dimerization of vinyl Grignard reagent using alkyl halides

Organomagnesium halides, commonly known as Grignard reagents, convert acid halides to tertiary alcohols. The reaction requires two equivalents of the Grignard reagent and proceeds via a ketone intermediate.
Grignard reagents are a source of carbanions and function as nucleophiles. The mechanism begins with the nucleophilic attack by the carbanion at the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs,...

The radical dimerization of ketones or aldehydes gives vicinal diols through a pinacol coupling reaction. However, the behavior of titanium metals used for the reaction as a source of electrons is unusual. When the reaction is carried out in the presence of titanium, diols can be isolated at low temperatures. Else titanium further reacts with diols, forming alkenes through the McMurry reaction.

The reaction of an ester with a Grignard reagent, followed by hydrolysis of the magnesium alkoxide salt in aqueous acid, yields a tertiary alcohol. In the case of formate esters, secondary alcohols are formed.
The reaction requires two equivalents of the Grignard reagent and introduces two identical alkyl groups, derived from the Grignard reagent, bonded to the hydroxyl-bearing carbon of the alcohol.
The reaction follows the typical nucleophilic acyl substitution mechanism. The Grignard...

Electrophilic addition of hydrogen halides, HX (X = Cl, Br or I) to alkenes forms alkyl halides as per Markovnikov's rule, where the hydrogen gets added to the less substituted carbon of the double bond. Hydrohalogenation of alkynes takes place in a similar manner, with the first addition of HX forming a vinyl halide and the second giving a geminal dihalide.

Grignard reagents are one of the most commonly used reagents used to synthesize alcohols from carbonyl compounds. Grignard reagents are organomagnesium halides with a highly polar carbon–magnesium bond. Due to the partial ionic nature of the C–Mg bond, the carbon functions as a strong nucleophile and attacks electrophiles like carbonyl carbon.
Magnesium from the reagent coordinates with carbonyl oxygen, further reducing the carbonyl carbon's electron density. Thus, the carbonyl carbon is a...

The Claisen rearrangement is a [3,3] sigmatropic rearrangement of allyl vinyl ethers to unsaturated carbonyl compounds. The rearrangement is a concerted pericyclic reaction proceeding via a chair-like transition state.