Since COMC

Since COMC II (1995), published work in this area has included several studies of the influence of catalyst and monomer structure on the dehydropolymerization of silanes, as this likely affect the chemistry of polymer chain growth. 

Functionalization of polysilanes by chemical modification (post-polymerization) was covered in COMC II (1995) (chapter Organopolysilanes, p 101), where the formation of precursor polysilanes with potentially functionalizable side groups such as chloride, type 34 (via HCI/AICI3 chlorodephenylation of PMPS), 6 triflate, type 35 (via triflate replacement of phenyl groups)135,137 or alkyl halide (via chloromethylation of phenyl groups,138,139 type 36, or addition of HC1 or HBr to double bonds140) was discussed. Four other precursor polysilanes, which utilize the reactivity of the Si-Cl or Si-H bond, have been successfully applied in functionalization since COMC (1995) perchloropolysilane, 17 (see Section 3.11.4.2.2.(i) for synthesis),103 poly[methyl(H)silylene-f >-methylphenylsilylene],... 

Metal-catalyzed reactions constitute the second major type of reactions in which organolead compounds act as major partners of the reacting systems. The study of these reactions has considerably increased since COMC (1995) review and they can be divided in two subtypes reactions in which the organolead reactant acts as a stoichiometric partner and reactions in which the organolead is only a catalytic species. In this section, only the reactions with stoichiometric organolead will be reviewed, and these reactions are catalyzed by copper, palladium or rhodium species. The second type is the metathesis reactions where the lead compound acts only as a promoter in a complex catalytic system and is reviewed in Section 9.09.4. 

The synthesis and spectroscopic features of a number of titanocene dicarbonyl derivatives have been reviewed previously.41 Typically, these complexes are prepared via magnesium reduction of the corresponding dihalide derivative under 1 atm of carbon monoxide. New compounds prepared since COMC(1995) are presented in Scheme 10. Mixed cyclopentadienyl phosphinimide dicarbonyl compounds such as (if-CsMcs)-(Buc3PN)Ti(CO)2 61 have also been isolated.46... 

The binding of CO to Pd has been quite extensively studied both experimentally and particularly theoretically since COMC (1995) was published. This has partly been due to the desire to understand the differences in stability of the group 10 carbonyls. While Ni(CO)4 is stable at ambient temperature, the Pd and Pt analogs have been observed only at low temperature in matrix isolation, as have Pd(CO)i 3. Palladium carbonyls also feature in a number of studies due to the use of metal carbonyls as reference complexes in the development of methods for estimating M-L bond energies and bond distances. The importance of Pd-CO interactions in both homogeneous and heterogeneous... 

The amount of work devoted to cobalt clusters seems to have dramatically decreased since COMC (1995) has appeared. Indeed, whereas in the previous report cobalt clusters were a wealthy research field, the number of research articles dealing with either new synthetic work involving Co clusters or various applications of these complexes has decreased significantly during the last decade. In fact, there have been relatively few reports of new types of cobalt clusters as compared to the previous period covered in COMC (1995). Most of what was achieved concerned reactions on already-described basic structures. 

There has been a relatively low number of new C04 clusters studied since COMC (1995) has appeared. 

This section surveys the rapid development which has occurred in the synthesis and structural analyses of mixed metal complexes in the 12 years since the publication of COMC (1995). The limited information which was available then on ate complexes has expanded into a more sophisticated understanding of how different metals gathered in a single complex influence the adopted structure and observed reactivity. 

This chapter covers publications between 1993 and 2005, since works in this field have been summarized in COMC (1982) and COMC (1995) until 1992. Cross-references to these previous editions and other leading book references or reviews have been included as much as possible. 

The chemistry of titanium has been reviewed in COMC (1982) and COMC (1995)40 41 as well as in Comprehensive Coordination Chemistry II. 2 Since then, several contributions have covered the coordination chemistry of cyclopenta-dienyltitanium carboxylates and related complexes,43 new titanium imido chemistry,44 the use of titanium(iv) chloride45 and isopropoxide46 in stereoselective synthesis, the preparation and synthetic applications of l, -dicarba-nionic titanium intermediates47 and organotitanium complexes,48 49 and titanium-catalyzed enantioselective... 

This chapter aims to update applications of hydroboration and hydroalumination in organic synthesis covered in both COMC(1982)1,la lg and COMC(1995),2,2a and we now review the literature for the period 1993-2004. Since 1993, the use of hydroboration in organic synthesis has been rapidly increasing and this is especially true of the enantio-selective variant. The application of hydroaluminations in organic synthesis, while not as widely used as hydrobora-tions, has also undergone significant development within the last decade. 

Over the years since the publication of COMC II (1995), different aspects of organopolysilane chemistry have been reviewed in many book chapters and review articles, and these are noted in the text below. Wide coverage of the area was also given in a book published a few years ago with chapters contributed from many experts in the field.1... 

There is a brief reference to electroreductive silicon polymer formation in COMC II (1995) (chapter Organopolysilanes, p 96), but the very limited extent of the field at that time precluded further comment. Since then, the field has seen considerable progress, and the mild conditions have permitted the synthesis of functionalized polymers of moderate molecular weight (104), an example of which is the co-polymer poly(rncthyM-rncthoxymethoxyphcnylsilylene)-r -poly(methylphenylsilylene), 26, with a protected phenolic function, which was prepared with a molecular weight Mw= 19,000.96 Deprotection afforded the phenolic polymer. Several reviews on the area have been published.113-115... 

Since this field is relatively new and coverage was brief in COMC II (1995), a summary of the development of the field is given, followed by recent results. 

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