The McMurry Coupling and Related Reactions

LiAlH4 [3] they also proposed that metallopinacols were intermediates in this reaction, since pinacols could be isolated as by-products in many cases. 

Such considerable improvements were possible after the design of more reactive low-valent titanium species and the use of new synthetic methods and procedures these will be presented in the second part of this chapter. In comparison with its synthetic applications, the mechanism of the McMurry reaction has received much less attention, undoubtedly because chemists were firmly convinced of the involvement of pinacolate intermediates and rejected, in spite of some evidence, the alternative pathway via carbenoid species. The last part of this chapter will describe the recent studies on the structure and mode of action of low-valent titanium species, as well as some accurate analyses of the reaction products, which have allowed new insights into the mechanism, revealing its dual nature. 

McMurry reactions will be presented in the following order intermolecular, intramolecular, mixed (tandem) couplings of aldehydes and ketones, and finally keto ester, oxoamide, and acetal couplings. All the compounds which serve as illustrations are listed in Tables 6.1-6.10, along with the titanium reagents and solvents used for their preparation and the yields of isolated products where not specified, the reactions were performed at solvent reflux temperature. 

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Ephritikhine, M. Villiers, C. The McMurry Coupling and Related Reactions. In Modem Carbonyl Olefination-, Takeda, T., Ed. Wiley-VCH ... 

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