Haloalkanes and Haloarenes

Haloalkanes

Alkanes in which one or more hydrogen atoms are replaced by halogen atoms, typically represented as R-X.

Finkelstein Reaction

R-X + NaI → R-I + NaX; a halogen exchange reaction where an alkyl halide is reacted with sodium iodide to yield the corresponding iodine derivative.

Swartz Reaction

R-X + MF → R-F + M; a reaction for preparing alkyl fluorides from alkyl halides using metallic fluorides.

Sandmeyer's Reaction

Ar-N2^+ + CuX → Ar-X + N2; a reaction that introduces halogens or cyanide groups into the benzene ring using diazonium salts.

Wurtz Reaction

2 R-X + 2 Na → R-R' + 2 NaX; a coupling reaction that uses alkyl halides and sodium to form higher alkanes.

Nucleophilic Substitution

Nu: + R-X → R-Nu + X-; a reaction where a nucleophile attacks an electrophilic carbon atom, replacing a leaving group.

Grignard Reagent

R-MgX + R' → R-R' + MgX2; an organomagnesium compound used in organic synthesis to form new carbon-carbon bonds.

Friedel-Crafts Alkylation

Ar + R-X → Ar-R + HX; a process that introduces alkyl groups into an aromatic system via alkyl halide and a Lewis acid catalyst.

Saytzeff Rule

Indicates that in elimination reactions, the more substituted alkene is the major product, typically represented as RCH2-CH2X → RCH=CHR' + HX.

Benzene Diazonium Chloride

Ar-N2^+ + R-X → Ar-R + N2 + HX; a reactive compound used to introduce other substituents into an aromatic ring.

Alkyl Halide

A compound derived from alkanes that possesses one or more halogen atoms as substituents.

Vinyl Halides

Halides that are attached to an alkene carbon, typically of the form R-CH=CH-X.

Aryl Halides

Halides attached to an aromatic ring; examples include chlorobenzene and bromobenzene.

Reactivity of Haloalkanes

Haloalkanes are more reactive than alkanes due to the polar C-X bond; reactivity patterns depend on the type of halogen.

SN1 Mechanism

A two-step nucleophilic substitution process where the rate-determining step involves the formation of a carbocation intermediate.

SN2 Mechanism

A one-step nucleophilic substitution where the nucleophile attacks the electrophilic carbon as the leaving group departs.

Nucleophilic Aromatic Substitution

A substitution reaction involving an aromatic compound and a nucleophile, usually occurring at positions with electron-withdrawing groups.

Hydrolysis of Alkyl Halides

The reaction of alkyl halides with water, leading to the formation of alcohols and byproducts.

Reagents in Halogenation

Common reagents include molecular chlorine (Cl2) or bromine (Br2), often used under light or heat to facilitate reactions.

Benchmark Reactions

Standard reactions that involve haloalkanes, often used to test the reactivity and properties of various alkyl halides.