条件控制的分离三基化:一种以多样性为导向的合成策略,用于高效地构建CF₃装饰的炭醇库

Bromination and chlorination of aromatic rings by electrophilic aromatic substitution reactions are easily achieved, but fluorination and iodination are difficult to achieve. Fluorine is so reactive that its reaction with benzene is difficult to control, resulting in poor yields of monofluoroaromatic products. To address this, Selectfluor reagent is used as a fluorine source in which a fluorine atom is bonded to a positively charged nitrogen.

The Friedel–Crafts acylation reactions involve the addition of an acyl group to an aromatic ring. These reactions proceed via electrophilic aromatic substitution by employing an acyl chloride and a Lewis acid catalyst such as aluminum chloride to form aryl ketone.

The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.

Friedel–Crafts reactions were developed in 1877 by the French chemist Charles Friedel and the American chemist James Crafts. Friedel–Crafts alkylation refers to the replacement of an aromatic proton with an alkyl group via electrophilic aromatic substitution. A Lewis acid catalyst such as aluminum chloride reacts with an alkyl halide to form a carbocation. The resulting carbocation then reacts with the aromatic ring and undergoes a series of electron rearrangements before giving the...

Structural Properties
Alkyl halides are halogen-substituted alkanes wherein one or more hydrogen atoms of an alkane is replaced by a halogen atom such as fluorine, chlorine, bromine, or iodine. The carbon atom in an alkyl halide is bonded to the halogen atom, which is sp3-hybridized and exhibits a tetrahedral shape.
Unlike alkyl halides, compounds in which a halogen atom is bonded to an sp2 -hybridized carbon atom of a carbon-carbon double bond (C=C) are called vinyl halides. Whereas aryl...

Several restrictions limit the use of Friedel–Crafts reactions. First, the halogen in the alkyl halide must be attached to an sp3-hybridized carbon for the Friedel–Crafts reactions to occur. Vinyl or aryl halides do not react since the carbocations formed are unstable under the reaction conditions. Second, Friedel–Crafts alkylation is susceptible to carbocation rearrangement, and the major products obtained have a rearranged carbon skeleton. In contrast, the acylium ion is...