Unsaturated Inorganic Compounds

An excellent review by Roth and Eisner (63) summarized the chemical defense substances found in arthropods up to 1962. These authors listed 31 defense substances of known structure one anhydride, three carboxylic acids, nine aldehydes, one furan, three hydrocarbons, two ketones, one lactone, eight quinones, and three inorganic compounds. Many of these same compounds (unsaturated aldehydes and quinones) have been found in other arthropods since 1962 (38). The compounds are discharged when the animal is disturbed by predators, and there can be no doubt that the action of most of them... 

Simple organic compounds such as CH4, CH3OH, CO2 Simple inorganic compounds such as SO, SiO, HF, KC1 Unsaturated hydrocarbon chains such as HC3N, HC5N Polycyclic aromatic hydrocarbons... 

The second mechanism is realized when organic or inorganic compounds are reduced by endogenous reductants (for example, by NADH or NADPH and the other components of mitochondrial or microsomal respiratory chains). The typical compounds are anthracycline antibiotics and carbon tetrachloride. CC14 is easily reduced by microsomes to the free radical CC13 , which is able to abstract a hydrogen atom from unsaturated lipids and initiate lipid peroxidation. Because of this, the CCl4-initiated lipid peroxidation is a reliable and frequently applied model system for the study of in vitro iron-independent lipid peroxidation and the effects of antioxidants (see for example Ref. [54]). 

The base-catalysed addition of thiols to Jt-electron-deficient alkenes is an important aspect of synthetic organic chemistry. Particular use of Triton-B, in place of inorganic bases, has been made in the reaction of both aryl and alkyl thiols with 1-acyloxy-l-cyanoethene, which behaves as a formyl anion equivalent in the reaction [1], Tetra-n-butylammonium and benzyltriethylammonium fluoride also catalyse the Michael-type addition of thiols to a,P-unsaturated carbonyl compounds [2], The reaction is usually conducted under homogeneous conditions in telrahydrofuran, 1,2-dimethoxyethane, acetone, or acetonitrile, to produce the thioethers in almost quantitative yields (Table 4.22). Use has also been made of polymer-supported qua-... 

The CVD method can form a polymethylsiloxane layer of 0.6-0.8 nm on the inorganic particles (Table 12.1.2). Especially, the polysiloxane-modified titanium oxide has been used for the additives to cosmetics. Moreover, residual Si-H group grafted on the particles reacted with unsaturated organic compounds in the presence of Speier catalyst (47), H2PtCl6, to be functionalized by organic pendant group [Reaction (11 ). ... 

Organolithium species may form coloured and EPR-active intermediates not only with conventional acceptors such as carbonyl or imine compounds [14-16] but also with unsaturated inorganic ions such as ambidentate thiocyanate-SCN the reaction between n-BuLi and NH4SCN in the presence of strongly ion-stabilizing hexamethylphosphoric triamide 0 = P(NMe2)3 (HMPA) eventually produced LiNCS 2 HMPA via some unusually colored intermediates and thiocyanate-based radical species [62]. 

Although HCN also adds to these unsaturated bonds to afford cyanohydrins and a-amino nitriles, use of TMSCN instead of HCN provides an efficient and safer route to these compounds. Cyanosilylation with TMSCN is accelerated by acid and base catalysts. In recent years a variety of organic and inorganic compounds have been found to work as effective catalysts, and much attention has been devoted for the development of chiral catalysts for asymmetric cyanosilylation of aldehydes, ketones, and imines. 

A new method of synthesis of selective platinum catalysts for the hydrogenation of unsaturated carbonyl compounds is presented. Platinum was deposited on the supports tailored with the monolayer of transition metal oxide. Selectivity of these catalysts strongly depended on the type of inorganic support as well as on the type of transition metal in the monolayer. Catalysts were tested in the hydrogenation of furfural, crotonaldehyde and cinnamaldehyde. Selectivity of the synthesis of the appropriate unsaturated alcohols was enhanced when compared with the reactions performed over classical Pt-metal oxide catalysts. 

UV /VIS radiation absorption spectroscopy, spectrophotometry determinations of aromatic and unsaturated organic compounds, including natural products direct and indirect quantitative determination of inorganic ions, organic molecules, and biochemicals... 

Cl2. —This radical may abstract hydrogen, add to unsaturated compounds, or oxidize by electron transfer. Extensive measurements of rate constants for its reaction with aliphatic, aromatic, and inorganic compounds have helped to clarify the relative importance of these reaction modes. 

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