Search results
Results from the WOW.Com Content Network
The reaction is considered Markovnikov as it results in water addition with same regiospecificity as a direct hydration reaction. Alkene hydroboration-oxidation: Stereospecific: Can only be syn addition – hydrogen and hydroxyl (-OH) are added to the same face. The reaction is anti-Markovnikov. Hydroxyl attaches to the less substituted carbon.
Alkenes react with percarboxylic acids and even hydrogen peroxide to yield epoxides: RCH=CH 2 + RCO 3 H → RCHOCH 2 + RCO 2 H. For ethylene, the epoxidation is conducted on a very large scale industrially using oxygen in the presence of silver-based catalysts: C 2 H 4 + 1/ 2 O 2 → C 2 H 4 O. Alkenes react with ozone, leading to the scission ...
The general chemical equation for the hydration of alkenes is the following: RRC=CH 2 + H 2 O → RRC(OH)-CH 3. A hydroxyl group (OH −) attaches to one carbon of the double bond, and a proton (H +) adds to the other. The reaction is highly exothermic. In the first step, the alkene acts as a nucleophile and attacks the proton, following ...
The same is true when an alkene reacts with water in an additional reaction to form an alcohol that involves carbocation formation. The hydroxyl group (OH) bonds to the carbon that has the greater number of carbon-carbon bonds, while the hydrogen bonds to the carbon on the other end of the double bond, that has more carbon–hydrogen bonds.
For example, polyester chains grow by reaction of alcohol and carboxylic acid groups to form ester links with loss of water. However, there are exceptions; for example polyurethanes are step-growth polymers formed from isocyanate and alcohol bifunctional monomers) without loss of water or other volatile molecules, and are classified as addition ...
Alkenes are precursors to aldehydes (R−CH=O), alcohols (R−OH), polymers, and aromatics. [1] As a problematic reaction, the fouling and inactivation of many catalysts arises via coking, which is the dehydrogenative polymerization of organic substrates. [2] Enzymes that catalyze dehydrogenation are called dehydrogenases.
Although these Lewis acids alone are able to induce polymerization, the reaction occurs much faster with a suitable cation source. [8] [9] The cation source can be water, alcohols, or even a carbocation donor such as an ester or an anhydride. In these systems the Lewis acid is referred to as a coinitiator while the cation source is the initiator.
In organic chemistry, an addition reaction is an organic reaction in which two or more molecules combine to form a larger molecule called the adduct. [1] [2] An addition reaction is limited to chemical compounds that have multiple bonds. Examples include a molecule with a carbon–carbon double bond (an alkene) or a triple bond (an alkyne).