Glaser Homocoupling and the Cadiot-Chodkiewicz Heterocoupling Reaction

Glaser Homocoupling and the Cadiot-Chodkiewicz Heterocoupling Reaction 53... 

Scheme 1. General description of (a) the oxidative Glaser-type homocoupling reaction and (b) nonoxidative Cadiot-Chodkiewicz heterocoupling (X= Br, I).

Some of the most useful synthetic transformations of terminal alkynes involve intermolecular and intramolecular homo- and cross-coupling reactions between their. sp-carbon centers, leading to butadiyne or polyyne derivatives. The two most widely used and practical systems are (i) oxidative homocoupling reactions, i.e. Glaser and Eglington reactions and (ii) heterocoupling reactions, i.e. Chodkiewicz-Cadiot coupling of a terminal alkyne with a haloalkyne. 

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