Neopentylmagnesium bromide

The only dialkylmagnesium compound whose enthalpy of formation has been measured is dineopentyl magnesium (s) —236.8 7.2 kJmol and (g) —74.3 7.6 kJmol. Unfortunately there are no enthalpies of formation for any of its isomers or homologs. We cannot even calculate the enthalpy of the Schlenk equilibrium because, although the enthalpy of formation of neopentylmagnesium bromide is for the ether solution, that for dineopentylmagnesium is not, and there is no experimental value for the enthalpy of solution. 

Reaction of VI with neopentylmagnesium bromide yields a product of molecular weight, as found by mass spectroscopy, corresponding to V (R = CH2CMe3). However, this compound exhibits all the properties of the tertiary arsane X (R = C CMes) (94). 

Evidence for Radicals from Ketones and Aldehydes. In the reaction of Grignard reagents such as the bulky neopentylmagnesium bromide with benzophenone considerable amounts of benzopinacol can be formed [76] ... 

Co-NHC complexes have been involved in the ortho C-H activation of imines to perform the synthesis of biaryl derivatives. The cross-coupling partner is an aryl chloride activated by neopentylmagnesium bromide. After hydrolysis of the imine, the corresponding biarylic ketones are obtained in moderate to excellent yield. 

There is no -hydrogen atom present in methyl- and neopentylmagnesium halide therefore, no reduction reaction products are observed in their reactions. The highest yield of reduction reaction product was obtained with 2-methyl-1-propylmagnesium bromide, which has one tertiary hydrogen atom on the )9-position. In a footnote, the authors made mention of an unpublished result in which the reaction of diisopropyl ketone with fert-butylmagnesium halide, which has nine primary hydrogens in the )ff-position, yielded 65% of the reduction reaction product. 

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