In synthesis of organometallic compounds

Reviews (a) Nesmeyanov, A. N. Sokolik, R. A. Methods of Elemento-Organic Chemistry, North-Holland, Amsterdam, 1967, Vol. 1. (b) Pelter, A., Smith, K. and Brown, H. C. Borane Reagents, Academic Press, London, 1988. (c) Miyaura, N. and Maruoka, K. In Synthesis of Organometallic Compounds, John Wiley Sons, Chichester, 1997, 345. 

TABLE 6. Electrical Conductivity and Dissociation Schemes for Some Complexes Used in Synthesis of Organometallic Compounds in Anodic Processes... 

The synthesis of organometallic compounds as a consequence of nuclear fission is also noteworthy In this way, for example, a powdered mixture of Fe(C5H5)2 and UjOg gives good yields of rutheno-cene and iodoferrocene on fission ... 

Decarboxylation reactions of metal carboxylates [Eq. (1)], are of increasing value in the synthesis of organometallic compounds (1-5). The reverse reaction, e.g., carbonation of Grignard and organolithium reagents (6,7), is a well-known source of carboxylic acids. Early reviews of the... 

Anyway, it is doubtful whether Letts and Collie thought about zinc as the catalyst of the reaction of tin with alkyl halides (in spite of their demonstration) since this fact was established considerably later. The authors also found that the reaction of EtI with a Sn—Zn alloy (33-50%) containing 5% of Cu gave a maximum yield of E Sn. Thus, long before Rochows s finding the catalytic influence of copper in the direct synthesis of organometallic compounds was observed636. 

Monoalkynyltitanium derivatives TiCl(C=CR)(OPr1)2 are prepared from the in situ formation of Ti(n) species and subsequent reaction with haloalkynes through an addition-/3-elimination mechanistic process, showing that this is a powerful method for the synthesis of organometallic compounds. Investigations are carried out in order to rule out the classical oxidative addition of the low-valent titanium species into the carbon-chloro bond. These complexes can further react chemoselectively with a wide range of functionalized electrophiles.21... 

The use of coordination compounds in SCFs is rather larger than one might initially expect [1]. The major applications can be divided into two broad categories (1) the transport of metals, which includes selective extraction, deposition of metal and oxide films and impregnation of metals as a route to composite materials and (2) synthesis and reactions, which covers a wide range of topics from the synthesis of oxides and other solid state materials to the reactions of organometallic compounds. This chapter focuses on the synthesis of organometallic compounds because this is the area where the majority of the new experimental techniques have been developed. The chapter complements chapter 3.1 and 3.2 which cover, respectively, vibrational and NMR spectroscopy, because IR spectroscopy, and to a lesser extent NMR, have been key tools in the exploration of this chemistry. 

A common procedure for the synthesis of organometallic compounds is the reduction of a carbon-halogen bond with a metal (M), as illustrated in Eq. (3.2). This simple equation ignores the role of solvent molecules and aggregated species in some of these reactions ... 

Phase-Transfer Catalyzed Synthesis of Organometallic Compounds and Complexes. Some organometallic compounds and complexes are efficiently synthesized using PTC methodology. For example, phenyltrihalomethyl mercury compounds, important precursors of dihalocarbenes generated in nonba-sic conditions are readily prepared by treatment of a haloform solution of phenyl mercury chloride with aqueous NaOH saturated with KF, in the presence of TAA salt (eq. 182). 

The one-step coupling reaction with metallic halides such as Pb(II) [111], Ge(IV) and several others have found wide application in the synthesis of organometallic compounds. Although the in situ reaction of 1,3-bisbromo-methylcyclopentane, magnesium and dichlorosilanes gave satisfactory yields of 3-sila[l,2,3]bicyclooctanes [112], similar reactions with dichlorogermanes resulted in poor yields [113] ... 

The reaction between metals and organic halides is often suitable for the synthesis of organometallic compounds of the most electropositive elements. On a laboratory scale, the derivatives of Li. Mg and Al, which are very important in synthetic work, are usually prepared in this way. Some illustrations of the method are given briefly here more detailed discussion of the preparation and properties of the compounds involved appears in Chapter 3. 

Use of reducing agent The starting materials for the synthesis of organometallic compounds which are readily available are halides, acetylacetonates etc. In many cases it is necessary to include a reducing agent to remove the halide and to provide electrons to the metal centre (p. 166). For rhodium and iridium, the reducing medium is provided by an alcohol. 

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