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The enolate product can either be trapped or alkylated. By using "masked functionality", it is possible to produce enolates that are not accessible by traditional methods. The "masked functionality" approach to regiospecific enolate formation has been widely used in the total synthesis of natural products.
Conversion of ascorbic acid (vitamin C) to an enolate. Enediol at left, enolate at right, showing movement of electron pairs resulting in deprotonation of the stable parent enediol. A distinct, more complex chemical system, exhibiting the characteristic of vinylogy. Ribulose-1,5-bisphosphate is a key substrate in the Calvin cycle of photosynthesis.
As a result, enolate ions are more common than enols in both laboratory and biological chemistry. Because they are resonance hybrids of two nonequivalent forms, enolate ions can be looked at either as vinylic alkoxides (C=C- O −) or as α-ketocarbanions (− C-C= O). Thus, enolate ions can react with electrophiles either on oxygen or on carbon.
Lithium enolates, one of the precursors to silyl enol ethers, [6] [7] can also be generated from silyl enol ethers using methyllithium. [ 15 ] [ 3 ] The reaction occurs via nucleophilic substitution at the silicon of the silyl enol ether, producing the lithium enolate and tetramethylsilane .
The resulting enolate attacks the activated olefin with 1,4-regioselectivity, forming a carbon–carbon bond. This also transfers the enolate to the electrophile. Since the electrophile is much less acidic than the nucleophile, rapid proton transfer usually transfers the enolate back to the nucleophile if the product is enolizable; however, one ...
A pastor was arrested over allegations of his lewd, forceful sexual behavior from several workers at his cleaning company — just a day after he preached at his Oklahoma church about forgiveness.
One alternative to hypervalent iodine oxidation that does not employ heavy metals is the attack of a metal enolate on dioxygen, followed by reduction of the resulting peroxide (equation ). The most popular method for the α-hydroxylation of carbonyl compounds is the Rubottom oxidation , which employs silyl enol ethers as substrates and peracids ...
Fans booed the American national anthem before NHL and NBA games in Canada on Tuesday night, a sign that some Canadians were still upset despite President Donald Trump’s 30-day pause on tariff ...