Santonic acid

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Santonic acid
Santonic-acid-2D-skeletal.png
Santonic-acid-from-xtal-3D-balls.png
Names
IUPAC name
(−)-2,3,3a,4,5,6,7,7a-octahydro-α,3a,5-trimethyl-6,8-dioxo-1,4-methano-1H-indene-1-acetic acid
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
PubChem CID
UNII
  • InChI=1S/C15H20O4/c1-7-9(16)6-10-14(3)4-5-15(10,8(2)13(18)19)12(17)11(7)14/h7-8,10-11H,4-6H2,1-3H3,(H,18,19) Yes check.svgY
    Key: UNPYYTKZOHYHMZ-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C15H20O4/c1-7-9(16)6-10-14(3)4-5-15(10,8(2)13(18)19)12(17)11(7)14/h7-8,10-11H,4-6H2,1-3H3,(H,18,19)
    Key: UNPYYTKZOHYHMZ-UHFFFAOYAW
  • O=C(O)C(C31C(=O)C2C(C(=O)CC1C2(CC3)C)C)C
Properties
C15H20O4
Molar mass 264.32 g mol−1
Density 1.184 g cm−3 [1]
Melting point 173 °C (343 °F; 446 K) [1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Santonic acid is an organic compound containing both carboxylic acid and ketone functionality.

It was synthesized from santonin by base-mediated hydrolysis of a lactone followed by a multistep rearrangement process by R. B. Woodward. [2]

Unusually for a carboxylic acid, santonic acid does not form hydrogen-bonded dimers in the crystalline phase. Rather, it adopts a polymeric structure, with individual santonic acid molecules linked by intermolecular carboxyl-to-ketone hydrogen bonds. [1]

Related Research Articles

Amide Chemical compound

In organic chemistry, an amide ( or or, also known as an organic amide or a carboxamide, is a compound with the general formula RC NR′R″, where R, R', and R″ represent organic groups or hydrogen atoms. The amide group is called a peptide bond when it is part of the main chain of a protein, and an isopeptide bond when it occurs in a side chain, such as in the amino acids asparagine and glutamine. It can be viewed as a derivative of a carboxylic acid RC OH with the hydroxyl group –OH replaced by an amine group −NR′R″; or, equivalently, an acyl group RC − joined to an amine group.

Carboxylic acid Organic compound

A carboxylic acid is an organic acid that contains a carboxyl group (C(=O)OH) attached to an R-group. The general formula of a carboxylic acid is R−COOH or R−CO2H, with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic acids occur widely. Important examples include the amino acids and fatty acids. Deprotonation of a carboxylic acid gives a carboxylate anion.

Ester Chemical compounds consisting of a carbonyl adjacent to an ether linkage

An ester is a chemical compound derived from an acid in which at least one –OH hydroxyl group is replaced by an –O– alkyl (alkoxy) group, as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils.

Ketone Class of organic compounds having structure RCOR

In chemistry, a ketone is a functional group with the structure R2C=O, where R can be a variety of carbon-containing substituents. Ketones contain a carbonyl group (a carbon-oxygen double bond). The simplest ketone is acetone (R = R' = methyl), with the formula CH3C(O)CH3. Many ketones are of great importance in biology and in industry. Examples include many sugars (ketoses), many steroids (e.g., testosterone), and the solvent acetone.

Acyl group

An acyl group is a moiety derived by the removal of one or more hydroxyl groups from an oxoacid, including inorganic acids. It contains a double-bonded oxygen atom and an alkyl group (R-C=O). In organic chemistry, the acyl group is usually derived from a carboxylic acid, in which case it has the formula RCO–, where R represents an alkyl group that is linked to the carbon atom of the group by a single bond. Although the term is almost always applied to organic compounds, acyl groups can in principle be derived from other types of acids such as sulfonic acids and phosphonic acids. In the most common arrangement, acyl groups are attached to a larger molecular fragment, in which case the carbon and oxygen atoms are linked by a double bond.

Oxime

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Aldol condensation

An aldol condensation is a condensation reaction in organic chemistry in which an enol or an enolate ion reacts with a carbonyl compound to form a β-hydroxyaldehyde or β-hydroxyketone, followed by dehydration to give a conjugated enone.

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Wolff rearrangement

The Wolff rearrangement is a reaction in organic chemistry in which an α-diazocarbonyl compound is converted into a ketene by loss of dinitrogen with accompanying 1,2-rearrangement. The Wolff rearrangement yields a ketene as an intermediate product, which can undergo nucleophilic attack with weakly acidic nucleophiles such as water, alcohols, and amines, to generate carboxylic acid derivatives or undergo [2+2] cycloaddition reactions to form four-membered rings. The mechanism of the Wolff rearrangement has been the subject of debate since its first use. No single mechanism sufficiently describes the reaction, and there are often competing concerted and carbene-mediated pathways; for simplicity, only the textbook, concerted mechanism is shown below. The reaction was discovered by Ludwig Wolff in 1902. The Wolff rearrangement has great synthetic utility due to the accessibility of α-diazocarbonyl compounds, variety of reactions from the ketene intermediate, and stereochemical retention of the migrating group. However, the Wolff rearrangement has limitations due to the highly reactive nature of α-diazocarbonyl compounds, which can undergo a variety of competing reactions.

Schmidt reaction

The Schmidt reaction is an organic reaction in which an azide reacts with a carbonyl derivative, usually a aldehyde, ketone, or carboxylic acid, under acidic conditions to give an amine or amide, with expulsion of nitrogen. It is named after Karl Friedrich Schmidt (1887–1971), who first reported it in 1924 by successfully converting benzophenone and hydrazoic acid to benzanilide. Surprisingly, the intramolecular reaction was not reported until 1991 but has become important in the synthesis of natural products.

The oxidation of secondary alcohols to ketones is an important oxidation reaction in organic chemistry.

Carbonyl reduction

In organic chemistry, carbonyl reduction is the organic reduction of any carbonyl group by a reducing agent.

Jones oxidation

The Jones oxidation is an organic reaction for the oxidation of primary and secondary alcohols to carboxylic acids and ketones, respectively. It is named after its discoverer, Sir Ewart Jones. The reaction was an early method for the oxidation of alcohols. Its use has subsided because milder, more selective reagents have been developed, e.g. Collins reagent.

References

  1. 1 2 3 A. P. J. Brunskill, H. W. Thompson and R. A. Lalancette (April 1999). "Santonic acid: catemeric hydrogen bonding in a γ,ε-diketo carboxylic acid". Acta Crystallogr. C. 55 (4): 566–568. doi:10.1107/S0108270198014231.
  2. Reusch, William (1999). "Base-catalyzed rearrangements Archived 2009-02-07 at the Wayback Machine ". In: Virtual Textbook of Organic Chemistry. Michigan State University. Retrieved September 10, 2008.