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  2. Dicarbonyl - Wikipedia

    en.wikipedia.org/wiki/Dicarbonyl

    General structure of 1,2-, 1,3-, and 1,4-dicarbonyls. In organic chemistry, a dicarbonyl is a molecule containing two carbonyl (C=O) groups.Although this term could refer to any organic compound containing two carbonyl groups, it is used more specifically to describe molecules in which both carbonyls are in close enough proximity that their reactivity is changed, such as 1,2-, 1,3-, and 1,4 ...

  3. Kröhnke pyridine synthesis - Wikipedia

    en.wikipedia.org/wiki/Kröhnke_pyridine_synthesis

    1,3-dicarbonyl compounds have also been shown to be viable starting materials in place of the α-pyridinium methyl ketone salts. [7] For example, treatment of 1,3-diketone 14 with base in ethanol followed by ammonium acetate, acetic acid, the corresponding enone and a Lewis acid yields 3-acyltriarylpyridines of the form 15.

  4. Solvent effects - Wikipedia

    en.wikipedia.org/wiki/Solvent_effects

    Many carbonyl compounds exhibit keto–enol tautomerism. This effect is especially pronounced in 1,3-dicarbonyl compounds that can form hydrogen-bonded enols. The equilibrium constant is dependent upon the solvent polarity, with the cis-enol form predominating at low polarity and the diketo form predominating at high polarity.

  5. Carbonyl group - Wikipedia

    en.wikipedia.org/wiki/Carbonyl_group

    Interactions between carbonyl groups and other substituents were found in a study of collagen. [3] Substituents can affect carbonyl groups by addition or subtraction of electron density by means of a sigma bond. [4] ΔHσ values are much greater when the substituents on the carbonyl group are more electronegative than carbon. [4] A carbonyl ...

  6. Mannich reaction - Wikipedia

    en.wikipedia.org/wiki/Mannich_reaction

    In organic chemistry, the Mannich reaction is a three-component organic reaction that involves the amino alkylation of an acidic proton next to a carbonyl (C=O) functional group by formaldehyde (H−CHO) and a primary or secondary amine (−NH 2) or ammonia (NH 3). [1] The final product is a β-amino-carbonyl compound also known as a Mannich base.

  7. Knorr pyrrole synthesis - Wikipedia

    en.wikipedia.org/wiki/Knorr_pyrrole_synthesis

    The Knorr pyrrole synthesis is a widely used chemical reaction that synthesizes substituted pyrroles (3). [1] [2] [3] The method involves the reaction of an α-amino-ketone (1) and a compound containing an electron-withdrawing group (e.g. an ester as shown) α to a carbonyl group (2). [4] The Knorr pyrrole synthesis

  8. Dibenzyl ketone - Wikipedia

    en.wikipedia.org/wiki/Dibenzyl_ketone

    Dibenzyl ketone, or 1,3-diphenylacetone, is an organic compound composed of two benzyl groups attached to a central carbonyl group. This results in the central carbonyl carbon atom being electrophilic and the two adjacent carbon atoms slightly nucleophilic.

  9. Paal–Knorr synthesis - Wikipedia

    en.wikipedia.org/wiki/Paal–Knorr_synthesis

    In organic chemistry, the Paal–Knorr synthesis is a reaction used to synthesize substituted furans, pyrroles, or thiophenes from 1,4-diketones.It is a synthetically valuable method for obtaining substituted furans and pyrroles, which are common structural components of many natural products.