Organometallic compounds synthesizing

An organometallic compound synthesized utilizing this scheme is di-cyclopentadienyl ytterbium (YbCp2), which is made by the reduction of di-cyclopentadienyl ytterbium chloride (YbCp2Cl) with ytterbium in tetrahydrofurane (Calderazzo et al., 1966). Unfortunately, experimental details were not reported. 

TABLE 1. Organometallic Compounds Synthesized by Electrolysis of Carbonyl Compounds... 

TABLE 2, Organometallic Compounds Synthesized during Electrolysis of Unsaturated Compounds... 

After a vigorous initial activity, whereby new fluorinated organometallic compounds were first synthesized, much of the research effort has decreased Some activity has been concerned with the reactions of perfluoroaromatic magnesium compounds... 

Organometallic compounds of the alkali metals (particularly LiMe and LiBu") are valuable synthetic reagents and have been increasingly used in industrial and laboratory-scale organic syntheses during the past 20 y,(86,94,95) annual produc-... 

When the antitumor activity of cisplatin was discovered, several research groups started to investigate the possible therapeutic applications of other metal-based, often organometallic, compounds. The organotin(lV) compounds that were first tested were those that were available or easily synthesized, like tri- or diorganotin(rV) halides. 

Table 2. Synthesis by recoil methods a partial list of radioactive organometallic compounds, other than the starting material, synthesized by recoil methods...

In a similar manner, the existence of (C5H5)Tc(C03) - and of Tc(CsH5)2 was demonstrated for the first time, starting from corresponding organometallic compounds of Mo, which undergoes [) decay to 99mTc. These compounds were also subsequently synthesized -and the chemical properties confirmed. 

Beside these free radical reactions of sulfur dioxide, its electrophilic reactions generating sulfmates with organometallic compounds - or sulfinic acids with arenes under Friedel-Crafts conditions are well known. To complete these three-component syntheses, the sulfmates prepared first are transformed to sulfones by reactions with appropriate electrophiles, discussed earlier in this chapter, i.e. equation 82. 

Second, as a logical development of the first approach, polyphosphazenes have been synthesized that bear phosphine units connected to aryloxy side groups (37). The phosphine units bind organometallic compounds, such as those of iron, cobalt, osmium, or ruthenium (38). In several cases, the catalytic activity of the metal is retained in the macromolecular system (39). A similar binding of transition metals has been accomplished through nido carboranyl units linked to a polyphosphazene chain (40). 

The new silazane 5 may be reacted with activated metals, organometallic compounds or simple metal amides, or may first be transformed to its lithium salt and then reacted with metal(II) chlorides [11]. In all these cases, metal derivatives of 5 are obtained with the general formula j [Mc (/BuO)Si 9N(9M, which have no further base coordinated to the metal. So far we have synthesized amides with M = Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Ba, all elements in oxidation state +2. X-ray structure determinations have been performed on the calcium, manganese, iron, zinc, and barium derivatives. 

Pyran syntheses can be conveniently discussed on the basis of catalytic processes, and in terms of reactions that involve stoichiometric processes on preformed organometallic compounds. 

Although the first report of an organometallic compound of the heavier alkaline earth metals appeared near the beginning of the twentieth century,291 the RMX Grignard analogs of Ca, Sr, and Ba never fulfilled their promise as general-purpose synthetic reagents. More difficult to form, less thermally stable, and less selective in their reactions than their Mg counterparts, the literature data of the compounds was often contradictory, and many syntheses were irreproducible (see Calcium, Strontium, and Barium in COMC (1982)). 

A large number of all citations to organozinc compounds deal with the use of these compounds as precursors for solid-state materials, particularly for MOCVD applications. The latter area has become so interdisciplinary and grown to such an extent that the editors of this edition considered it prudent to devote an entire volume (Volume 12) to the use of organometallic compounds in materials chemistry. While the syntheses and structures of potential organozinc precursors for such applications will be treated in this chapter, the detailed aspects of the conversion of organozinc compounds to solid-state materials are the topic of Volume 12. 

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