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As a reaction to create an acetal proceeds, water must be removed from the reaction mixture, for example, with a Dean–Stark apparatus, lest it hydrolyse the product back to the hemiacetal. The formation of acetals reduces the total number of molecules present (carbonyl + 2 alcohol → acetal + water) and therefore is generally not favourable ...
Acetaldehyde forms a stable acetal upon reaction with ethanol under conditions that favor dehydration. The product, CH 3 CH(OCH 2 CH 3) 2, is formally named 1,1-diethoxyethane but is commonly referred to as "acetal". [39]
The latter reagent in itself is an acetal and therefore the reaction is actually a cross-acetalisation. Kinetic reaction control results from 2-methoxypropene as the reagent. D-ribose in itself is a hemiacetal and in equilibrium with the pyranose 3. In aqueous solution ribose is 75% pyranose and 25% furanose and a different acetal 4 is formed.
Ethylene glycol protects a ketone (as an acetal) during an ester reduction, vs. unprotected reduction to a diol. A protecting group or protective group is introduced into a molecule by chemical modification of a functional group to obtain chemoselectivity in a subsequent chemical reaction.
Polyoxymethylene (POM), also known as acetal, [4] polyacetal, and polyformaldehyde, is an engineering thermoplastic used in precision parts requiring high stiffness, low friction, and excellent dimensional stability.
One common type of spiro compound encountered in educational settings is a heterocyclic one— the acetal formed by reaction of a diol with a cyclic ketone. The common atom that connects the two (or sometimes three) rings is called the spiro atom. [2]:
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(Left) Lewis acid-promoted acetal substitution may proceed via either the S N 1 or the S N 2 mechanism. (Right) Denmark's model system for acetal substitution mechanism. If the S N 1 mechanism is operative for the acetal substitution, the two reactions shown here should proceed via the same oxocarbenium ion and give similar stereochemical ...