Unsaturated carbon bonds

A part of the mechanistic spectrum is supported by the [2+2] cycloaddition reactions between the unsaturated carbon bonds and carbonyl compounds [24]. 

Four-membered ring formation between unsaturated carbon bonds and carbonyl compounds is a photochemical reaction [25], This is an excited-state reaction in the delocalization band (Scheme 6). 

Substituents with Unsaturated Carbon Bonded To Ring Nitrogen... 

The aldehyde region unsaturated carbon bonded to oxygen... 

DOUBLE-BONDED CARBON COMPOUNDS OR UNSATURATED CARBON BONDS... 

Place the plate in a sealed chamber saturated with I2 vapor and incubate for 5 min. The I2 will react with unsaturated carbon bonds present in the lipids and produce yellow spots on the plate. 

Ionic liquids were initially developed as solvents for electrochemical applications. The electrochemical window of clean ionic liquids can be huge/11 allowing for a wide range of redox reactions/2,31 It has further been demonstrated that they are also suitable solvents for enzymatic oxidations14 71 but both topics are beyond the scope of this book. Only transformations that involve the metal-catalysed addition of oxygen to unsaturated carbon bonds as well as the oxidation of alcohols, aldehydes and ketones to their corresponding ketones, carboxylic acids and esters shall be discussed in this chapter. 

Figure 1.8 Hydrogenation of the double (unsaturated) carbon bond.

Since it is unanimously agreed that MTBE is eUminated via OH radicals, many studies have been performed in order to elucidate the mechanistic pathway of the conversion. OH radicals react with organic molecules by the abstraction of hydrogen from C - H or O - H bonds, via hydroxyl group addition to unsaturated carbon bonds or the interaction with N-, P-, and S-containing bonds [32]. Since in the MTBE molecule no unsaturated carbon bonds and no N-, P-, or S-atoms are present the initial reaction has to concentrate on the abstraction of H atoms or the cleavage of the C - 0 bond. 

The formation of chromophoric groups such as carbonyls (C=0) and unsaturated carbon bonds (C=C and C=C) in the backbone of a polymer results in colour formation in white and transparent plastics and discolouration of coloured materials. Chromophoric groups can be formed when polymers undergo oxidation (see section 6.2.3) or hydrolysis (see section 6.2.4). 

THE ALDEHYDE REGION UNSATURATED CARBON BONDED TO OXYGEN... 

CNT can be treated using purification process by exposing them to strong oxidizing acids to introduce hydroxyls and carboxyl groups on the CNT surface thus can interact with unsaturated carbon bonds of the elastomers." ... 

Enzymatic reduction of the a,p-unsaturated carbon bond in dtral. J. Mol. Catal. B Enzym., 38,126-130. 

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