Lewis acid

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Le·wis ac·id

(lū'wis),
an acid that is an electron pair acceptor.

Le·wis acid

(lū'is as'id)
An acid that is an electron pair acceptor.

Lewis acid

A substance that accepts an electron pair from a base, forming a covalent bond with the base.

Lewis,

Gilbert N., U.S. chemist, 1875-1946.
Lewis acid - an acid that is an electron pair acceptor.
References in periodicals archive ?
It can be easily predicted that other Lewis acids that promote glycosylations using glycosyl fluorides will be found in the future based on the concept of fluorophilicity.
Then, optionally, a second activator component and/or Lewis acid and subsequently the metal complex were added, and the resulting mixture was allowed to stir for an additional 30 minutes.
Very often these initiators eliminate the drawbacks presented by the more common protic and Lewis acid catalysts in that they are chemically well defined and allow a quantitative initiation reaction to proceed without complicated side reactions or the need for cocatalysts and promoters.
A mix of oligomers, resembling coal tar pitch, is created by co-polymerisation of anthracene with benzyl alcohol in the presence of Lewis acids at temperatures of around 200 [degrees]C (Otani, 1986)
Several dopants have been proposed for inducing PANI, for example, protonic acid (6), Lewis acid (7), and transition-metal salts (8).
The Knoevenagel condensation of aldehydes with active methylene compounds is widely employed in organic synthesis and are catalyzed by bases [6,7] , Lewis acids [8], surfactants [9], zeolites [10] and heterogeneous catalysts[ 11,12] in aqueous medium or solvent free conditions [13].
The technique uses the Lewis acid tris(pentafluorophenyl) borane and the Lewis base tetramethylpiperidine that have been modified to be too large to get close enough to form an adduct (Lewis bases, which carry a lone pair of electrons, can bond with Lewis acids to form molecules called adducts).
Scientists mainly in Japan, but also in China, Singapore, France, Canada, and the US are the authors, with chapters on the many uses of Lewis acid as a catalyis for organic synthesis including Mg(II), Zn(II), Ca(II), Li(I), Na(I), K(I), Boron(III), Al(III), Ga(III), IN(III), Si(IV), Sn(II & IV), Bismuth(III), and polymer-supported metal Lewis acids, among others.
the famous Koppel-Palm equation), substituent effects, photoelectron spectroscopy, gas-phase equilibriums involving both Bronsted and Lewis acids and bases, acid-base equilibriums in different media starting from the most common--water--and ranging to such an exotic one (for charge-transfer reactions) as heptane, where until recently the accurate determination of [pK.
Boronic acids are well-known Lewis acids, which can accept the electron pairs from oxygen of an alcohol.
These reactions are catalyzed by Lewis Acids and are the mechanism by which the resin reaction proceeds.

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