Grignard reagents quantitative determination

For the development of the LANA route, analytical techniques such as GC, TLC, FIPLC, NMR, and GC/MS were used. GC methods were developed to monitor formation of the Grignard reagent. Since all of the components of the LANA route are unstable to the elevated temperatures of GC, FIPLC and TLC techniques were chosen for qualitative and quantitative analysis of reaction samples, to monitor reaction progress, and to determine the purity of intermediates and final product. Because the process development time was limited and the LANA process was entirely dependent on HPLC analysis, we set criteria for the development of HPLC methods ... 

Nishioka, Watanabe, Abe, and Sono (48) carried out an extensive study of the Grignard reagent catalyzed polymerization of methyl methacrylate in toluene with respect to tactidty of the resulting polymers. The tactidty of the polymer was determined quantitatively by nuclear magnetic resonance analysis. It was found that the stereo-regularity depended on the nature of the R group of the Grignard... 

Alkyl phenyl telluriums and diaryl telluriums react with Grignard reagents in THF or diethyl ether in the presence of catalytic amounts of nickel- or cobalt-phosphane complexes. Tellurium is precipitated. The organic groups combine to form in most cases all three possible coupling products in ratios determined by reaction conditions . The reaction of ( Z,)-phenylethenyl phenyl tellurium and phenyl magnesium bromide formed almost exclusively ( Zj-stilbene in quantitative yield. ( ZJ-Ethoxycarbonylethenyl phenyl tellurium and phenyl magnesium bromide reacted differently ( Fj-ethoxycarbonyl-(phenyl)-ethene and diphenyl tellurium were produced. Tellurium was not formed. ... 

Chirality can be introduced by use of an asymmetric alcohol and/or an asymmetric catalyst. The optical yield and predominant configuration around silicon were determined by conversion of the diastereomeric alkoxysilanes to a trisub-stituted silane of known configuration and maximum specific rotation. Reaction of Grignard reagents to this end is both quantitative and stereospecific. 

Steinmeyer et al applied gas chromatography to the analysis of butyltin bromides. They showed that the butyltin bromides may be quantitatively converted to their more volatile butylmethyltin analog with methyl Grignard reagent and then determined by gas liquid chromatography with an estimated accuracy of about - 2%. Direct chromatography of the alkyltin bromides appeared to produce severe sample decomposition. The method is stated to be applicable to a number of tetralkyl and/or tetraryltins and alkyl or aryltin halides. 

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