Organozinc compounds Subject

Dimethylzinc was the first organozinc compound to be studied by mass spectrometry (MS), as part of early MS studies performed by Aston aiming to examine natural abundances of Zn isotopes. Soon thereafter, Bainbridge showed that Aston s data were imprecise because the formation of hydride ions [ZnH]+ was overlooked, and therefore their contribution to the measured abundances of Zn isotopes was not taken into consideration. In the years that followed, numerous studies addressed the subject of Zn isotopic abundances In 2001, the data presented in Table 1 were accepted as the most accurate. It was by mass spectrometry that this best measurement from a single terrestrial source was obtained. 

Organozinc compounds have been widely used as components of initiators for polymerizations of various monomers. Although a tremendous number of the research works on the subject are available in the literature, this chapter describes only the main features of the use of organozinc compounds as initiators for polymerizations. All patents were omitted in this review. 

The different routes for the preparation of organozinc compounds are summarized in Scheme 1. Detailed experimental protocols including important tips can be found in references 6 and 7. In the last decade, this subject was included in several reviews dealing with the applications of polyfunctional organozinc compounds in organic synthesis. " ... 

The research on asymmetric organozinc additions to carbonyl compounds started in 1984 when Oguni and Omi obtained 49% e.e. in the reaction of diethylzinc with benzaldehyde catalyzed by (X)-leucinol. Since then, a huge number of chiral (see Chiral) catalysts, mostly derived from amino alcohols, have been developed and the subject has been extensively reviewed. 63.264 jjjg highly enantioselective (see Electrophile) ligand (—)-3-exo-dimethylaminoisobomeol [(-)-DAIB] developed by Noyori and coworkers in 1986 is still used even if its application is mostly limited to aromatic and heteroaromatic aldehydes (equation 62). As shown by previous studies, chiral (see Chiral) ligands have a dual... 

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