Cadiot–Chodkiewicz coupling

Cadiot–Chodkiewicz coupling
Named after	Paul Cadiot ; Wladyslaw Chodkiewicz
Reaction type	Coupling reaction
Identifiers
Organic Chemistry Portal	cadiot-chodkiewicz-coupling
RSC ontology ID	RXNO:0000100

The Cadiot–Chodkiewicz coupling in organic chemistry is a coupling reaction between a terminal alkyne and a haloalkyne catalyzed by a copper(I) salt such as copper(I) bromide and an amine base.^[1]^[2] The reaction product is a 1,3-diyne or di-alkyne.

The reaction mechanism involves deprotonation by base of the terminal alkyne proton followed by formation of a copper(I) acetylide. A cycle of oxidative addition and reductive elimination on the copper centre then creates a new carbon-carbon bond.

Scope

Unlike the related Glaser coupling the Cadiot–Chodkiewicz coupling proceeds selectively and will only couple the alkyne to the haloalkyne, giving a single product. By comparison the Glaser coupling would simply produce a distribution of all possible couplings. In one study^[3] the Cadiot–Chodkiewicz coupling has been applied in the synthesis of acetylene macrocycles starting from cis-1,4-diethynyl-1,4-dimethoxycyclohexa-2,5-diene. This compound is also the starting material for the dibromide through N-bromosuccinimide (NBS) and silver nitrate:

The coupling reaction itself takes place in methanol with piperidine, the hydrochloric acid salt of hydroxylamine and copper(I) bromide.^[3]

References

^ Chodkiewicz, W. Ann. Chim. Paris 1957, 2, 819–69.
^ Cadiot, P.; Chodkiewicz, W. In Chemistry of Acetylenes; Viehe, H. G., Ed.; Marcel Dekker: New York, 1969; pp. 597–647.
^ ^a ^b Bandyopadhyay, Arkasish; Varghese, Babu; Sankararaman, Sethuraman (2006). "Synthesis of 1,4-Cyclohexadiene-Based Acetylenic Macrocycles with Cadiot–Chodkiewicz Coupling. Structure of a Tub-Shaped Tetrameric Container". Journal of Organic Chemistry. 71 (12): 4544–4548. doi:10.1021/jo0605290. PMID 16749787.

[1] Chodkiewicz, W. Ann. Chim. Paris 1957, 2, 819–69.

[2] Cadiot, P.; Chodkiewicz, W. In Chemistry of Acetylenes; Viehe, H. G., Ed.; Marcel Dekker: New York, 1969; pp. 597–647.

[JOC2006-3] Bandyopadhyay, Arkasish; Varghese, Babu; Sankararaman, Sethuraman (2006). "Synthesis of 1,4-Cyclohexadiene-Based Acetylenic Macrocycles with Cadiot–Chodkiewicz Coupling. Structure of a Tub-Shaped Tetrameric Container". Journal of Organic Chemistry. 71 (12): 4544–4548. doi:10.1021/jo0605290. PMID 16749787.

[1]

[2]

[3]

v t e Alkynes
Ethyne (C₂H₂) Propyne (C₃H₄) Butyne (C₄H₆) 1 2 Pentyne (C₅H₈) 1 2 Hexyne (C₆H₁₀) 1 2 3 Heptyne (C₇H₁₂) Octyne (C₈H₁₄) 2 4 Nonyne (C₉H₁₆) Decyne (C₁₀H₁₈) 1 5
Preparations	Cracking Dehydrogenation of alkane, alkene Alkylation of alkynyl anion Dehydrohalogenation of dihaloalkane Fritsch–Buttenberg–Wiechell rearrangement Corey–Fuchs reaction Seyferth–Gilbert homologation
Reactions	Deprotonation Hydrogenation Halogenation Hydration Hydroboration Hydrohalogenation Alkynylation Thiol-yne reaction Alkyne trimerisation Diels–Alder reaction Pauson–Khand reaction Azide-alkyne Huisgen cycloaddition Sonogashira coupling Cadiot–Chodkiewicz coupling Glaser coupling Favorskii reaction

Scope

See also

References