Reactivity of Grignard reagents

Because of the high reactivity of Grignard reagents, calorimetric measurements require total exclusion of air and moisture and vacuum tight equipment must be used. The following three reactions (equations 3-5) have usually been studied formation, protonation and reaction with bromine. 

VII. CONCLUDING REMARKS ELECTROCHEMICAL DATA IN THE ELUCIDATION OF REACTIVITY OF GRIGNARD REAGENTS... 

One year later, in 1934, Vavon and co-workers [5] determined the relative reactivities of Grignard reagents with a different type of substrates benzoic acid esters. Steric requirements played a role when the alcohol component of the ester was changed from primary, to secondary, to tertiary the relative rates of reactions of ethylmagnesium bromide were 400 40 1, respectively. The relative rates of reaction of ethyl-, isopropyl-, n-butyl-, and phenylmagnesium bromide with ethyl benzoate decreased in this order. The reaction with rert-butylmagnesium chloride was reported to be extremely slow."... 

An investigation of the reactivity of the complexes [Tp ]MgR is important both in terms of determining the reactivity of the Mg-C bond in a well-defined coordination environment, but also in terms of providing a comparison with the reactivity of Grignard reagents. Aspects of the reactivity of [Tp ]MgR are considered in the following sections [21]. 

From a historic perspective, in 1936 Gilman and Straley (3) discovered that catalytic amounts of a copper salt lead to an increased reactivity of Grignard reagents. A little later, in 1941, Kharasch and Twaney (4) found that Grignard reagents react with a,/3-unsaturated ketones to afford products that result from... 

Grignard (-like) reactions are emerging solid-phase reactions that have not yet been exhaustively studied. One is, therefore, tempted to conclude that the use of Grignard reactions in solid-phase chemistry is under-developed. A reason might be that the high reactivity of Grignard reagents coupled with the need for anhydrous conditions complicates with solid supported synthesis. 

Reactivity of Grignard Reagents—Water, Heating/Cooling Fluids... 

Radiation boundary condition 197 Radical coupling/disproportionaiion 248 Radical mechanism and early evidence 7-8 Radical probes 11-13 Reactivity of Grignard reagents 171 Reactivity scries 8-11 Recurrence theorem 199 Reduction potentials ol organic halides 36 Redueiive dimeri/ation ol carbonyl compounds 21 Rieke-ntayncsium 289 Grignard reactions 257... 

The reactions of organolithium compounds proceed similar to those of the Grignard reactions. However, organolithium compounds are used especially for the following three reactions in which the reactivities of Grignard reagents are low, as described above. 

Organomagnesium reagents can also be obtained from organic iodides and magnesium metal using ionic liquids like -butylpyridinium tetrafluoroborate ([bpy][Bp4]) as solvent. Some unusual reactivity of Grignard reagents was observed in these solutions. ... 

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