Carbon linkage, unsaturated

Halogenation. Halogens and halogen acids add readily to the unsaturated carbon linkages of the cyclopentadiene molecule. By such additions a series of halogenated derivatives range, in the case of the chloride, from 3-chlotocydopentene to tetrachlorocyclopentane. Of all the possible chloto derivatives of CPD, only hexachlorocyclopentadiene [77-47-4] ever reached commercial status. It was used as an insecticide, but this use has been discontinued because of its toxicity (see Chlorocarbons and chlorohydrocarbons, toxic aromatics). It can be prepared by a Hquid phase chlorination of CPD below 50°C (29). 

Keywords H-P addition Unsaturated carbon linkage Transition metal complex Homogeneous catalysis... 

Thione adds to the unsaturated carbon—carbon linkage of maleic anhydride probably by a Michael-type reaction, subsequent cyclization results in the synthesis of 4-thiazolidinone derivatives. The reaction of thi-... 

Hydrosilylation, the addition of a Si-H bond across an unsaturated carbon-carbon linkage, is a facile and atom-economical route to organosilanes, which can be functionalized further, for example, using the Tamao or Fleming oxidation protocol [33],... 

Significant progress in organolanthanide-catalyzedhydroamination over the last two decades has sparked the interest in the development of analogous catalytic hydrofunctionalization protocols. Catalytic hydrophosphination of unsaturated carbon-carbon linkages offers an attractive atom-economic route to phosphines [87,177], It should be noted that inter- and intramolecular hydrophosphinations are also... 

Hopff, H. and Rautenstrauch, C.W., Production of addition products from dienes and compounds having an unsaturated carbon linkage activated by substituents, US Patent US 2262002, 1939. 

Tanaka M (2012) Recent progress in transition metal-catalyzed addition reactions of H-P(O) compounds with unsaturated carbon linkages. Top Organomet Chem. doi 10.1007/ 3418 2011 20... 

Recent Progress in Transition Metal-Catalyzed Addition Reactions of H-P(O) Compounds with Unsaturated Carbon Linkages... 

The ring-opening reaction usually results in the formation of a new unsaturated linkage. When this is a carbon-carbon double bond, the further reaction of this group during polymerization leads to a crosslinked (and insoluble) structure and can be a serious problem when networks are undesirable. In many of the applications mentioned above, crosslinking is desirable. 

Carbonyl groups may be hydrogenated catalytically, as carbon-carbon unsaturated linkages were (p. 191). It is, however, normally more difficult to effect the catalytic reduction of C=0 than of C=C, C=C, C=N, or C N, so that selective reduction of the former—in the presence of any of the latter—cannot normally be achieved catalytically. This can, however, be done with various, usually complex, metal hydrides. 

Han, L.-B. and Tanaka, M. Transition metal-catalyzed addition reactions of H-heteroatom and inter-heteroatom bonds to carbon-carbon unsaturated linkages via oxidative additions, Chem. Commun., 395, 1999. 

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