Organometallic species organotin compounds

Tin has a strong tendency to form organometallic complexes. Organotin compounds are used in marine antifoulant agents. Of course, there can be many tin species... 

The relative reactivities of organometallics containing group 14 elements are closely associated with the electronegativity and dissociation energy of the M—C bonds of the elements. For example, some organotin compounds such as allylstannanes are easily decomposed to form radical species whereas homolysis of the carbon-silicon bond of allylsilanes is rarely achieved, which reflects the dissociation energy of the respective M—C bonds. 

We have also initiated MUssbauer spectroscopic studies of photochemical reactions of inorganic and organometallic compounds (iron chelate complexes, iron carbonyl and organotin compounds) isolated in low temperature matrices. Such systems provide a complimentary approach to solid-phase photochemistry since the reaction mechanisms may be simplified by isolating the reactant molecules in inert matrices (light transmission through the reactant is also facilitated by diluting tlie colored reactant with a transparent medium). Furthermore, we have a hope for the possible outcome of such studies — their application to syntheses of novel species which may be unstable at ordinary temperatures, unless trapped in inert matrices. 

Oxidative cross-coupling reactions may start from two organometallic species to yield a new C-C single bond (for the oxidative C-X formation, see 10.4). A prototypical example is stated in Scheme 5-143. In this procedure, palladium is first oxidized by the haloketone 2-chloro-2-phenylacetophenone, and the resulting palladium OPdCl complex then accepts both organozinc and organotin compounds in a double transmetalation to yield an oxidative cross-coupling. ... 

Although inhibitors are deliberately added to the silicone formulation to control cure rate, unwanted cure inhibition can be caused by other species that react to form strong complexes with the platinum catalyst. Most notable of these undesired inhibitors include organotin and other organometallic compounds, sulfur, polysulfides, polysulfones or other sulfur-containing materials, amines, urethanes or amine-containing materials, unsaturated hydrocarbons in plasticizers, and some solder flux residues. 

Formation constants for complex species of mono-, di-, and trialkytin(rV) cations with some nucleotide-5 -monophosphates (AMP, LIMP, IMP, and GMP) are reported by De Stefano et al. The investigation was performed in the light of speciation of organometallic compounds in natural fluids (I = 0.16-1 moldm ). As expected, owing to the strong tendency of organotin(IV) cations to hydrolysis (as already was pointed above) in aqueous solution, the main species formed in the pH-range of interest of natural fluids are the hydrolytic ones. ... 

In comparison with the photochemistry of organosilicon compounds, the photochemistry of organometallic compounds of the heavier Group 14 elements has received little attention. In recent years, however, a number of synthetically useful photoreactions of such species have been developed, and it would seem opportune to review this area of research. In particular, organogermanium and organotin reagents are becoming... 

HIOC is a term that refers to organic compounds that can be ionised in the environment and thus are present in two or more species. Basically, the group of HIOCs includes weak organic acids and bases and organometallic compounds, e.g. organotins. This latter group will be treated separately (see Section 2.2.4). 

The most important substrates for substitutions of this type are alkenyl and aryl triflates, bromides, or iodides (Sections 16.1-16.4). The most important organometallic compounds to be introduced into the substrates contain Cu, Mg, B, Zn or Sn. The metal-bound C atom can be sp2-, sp2-, or. sp-hybridized in these compounds, and each of these species, in principle, is capable of reacting with unsaturated substrates. Organocopper compounds often (Section 16.1, 16.2), but not always substitute without the need for a catalyst (Section 16.4.5). Grignard compounds substitute in the presence of catalytic amounts of Ni complexes (Section 16.3), while organoboron (Section 16.4.2), organozinc (Section 16.4.3) and organotin (Section 16.4.4) compounds are typically reacted in the presence of Pd complexes (usually Pd(PPhj)4). 

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