Lead—oxygen bonds

Trimethyl-lead methoxide (CH3)3PbOCH3 is polymericio, as shown in Fig. 6. The properties of the lead-oxygen bond in the organolead alkoxides and the organolead oxides... 

Benzylenol ethers rearrange in an apparently similar fashion via photolytic fission of the benzyl-oxygen bond and subsequent recombination steps. Irradiation in quartz of a cyclohexane solution of 3-benzyloxycholesta-3,5-diene (250) leads to 23% (251), 13% (252) [presumably formed from (251) during workup] and 10% (253). ... 

A related molecule is hydrogen peroxide. Again, it might be expected that rotation (around the oxygen-oxygen bond) would lead to three all-staggered conformers. 

Hydrolysis is one of a family of reactions which leads to the transformation of pollutants. Under environmental conditions, hydrolysis occurs mainly with organic compounds. Hydrolysis is a chemical transformation process in which an organic RX reacts with water, forming a new molecule. This process normally involves the formation of a new carbon-oxygen bond and the clearing of the carbon-X bond in the original molecule ... 

The initial step is an oxidative addition of RhCI(PPh3)3 to a C-0 bond of the ester moiety and produces rhodium-carbon and rhodium-oxygen bonds. Adjacent rhodium species can undergo further reaction with the formation of anhydride linkages. This anhydride formation may occur between adjacent pairs of reactants, between pairs in the same chain, or between pairs that are present in different chains. All of these reactions are observed, and in however the last reaction is the one of interest here since this leads to cross-linking and char formation. Rhodium is present in both the chary material and in the soluble fractions. From the reaction pathway in order for rhodium elimination to occur, two rhodium-inserted... 

In this reaction, only the benzylic carbonate can react readily since cleavage of the benzylic carbon-oxygen bond leads to a stabilized carbocation while no such stabilization would exist for the hypothetical products which would be obtained by cleavage of the phenyl carbonate. The benzylic carbocation intermediate which is formed can either eliminate to the corresponding styrene 4 or recombine with the nucleophilic methanol which is formed by decarboxylation. It is the latter reaction which appears to prevail at room temperature as the ether 2 can be isolated in excellent yield. Subsequent heating in the presence of acid catalyst drives the reaction to the elimination product 6 and free methanol. 

Poly(phenylene oxide) PPO, or poly(phenylene ether) PPE, is an engineering polymer developed by General Electric. It concerns the oxidative coupling of phenols discovered in 1956 by Allan S. Hay [21], Oxidative coupling leads to the formation of carbon-oxygen bonds between carbon atoms 2,4, and 6 and the phenolic oxygen atom. To avoid coupling with carbon atoms 2 and 6, alkyl substituents at these two positions were introduced. In addition to the polymer a 4,4 dimer is formed, named diphenoquinone (DPQ). The... 

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