Pinner reaction

Last updated
Pinner reaction
Named after Adolf Pinner
Identifiers
Organic Chemistry Portal pinner-reaction
RSC ontology ID RXNO:0000361

The Pinner reaction refers to the acid catalysed reaction of a nitrile with an alcohol to form an imino ester salt (alkyl imidate salt); this is sometimes referred to as a Pinner salt. [1] The reaction is named after Adolf Pinner, who first described it in 1877. [2] [3] [4] Pinner salts are themselves reactive and undergo additional nucleophilic additions to give various useful products: [5] [6]

Reaction-pinner2.png

Commonly, the Pinner salt itself is not isolated, with the reaction being continued to give the desired functional group (orthoester etc.) in one go. The imidium chloride salts is thermodynamically unstable, and low temperatures help prevent elimination to an amide and alkyl chloride. [8]

It should be appreciated that the Pinner reaction refers specifically to an acid catalyzed process, but that similar results can often be achieved using base catalysis. The two approaches can be complementary, with nitriles which are unreactive under acid conditions often giving better results in the presence of base, and vice versa. [9] The determining factor is typically how electron-rich or poor the nitrile is. For example: an electron-poor nitrile is a good electrophile (readily susceptible to attack from alkoxides etc.) but a poor nucleophile would typically be easier to protonate than to participate in the reaction and hence would be expected to react more readily under basic rather than acidic conditions.

See also

Related Research Articles

<span class="mw-page-title-main">Phthalic anhydride</span> Chemical compound

Phthalic anhydride is the organic compound with the formula C6H4(CO)2O. It is the anhydride of phthalic acid. Phthalic anhydride is a principal commercial form of phthalic acid. It was the first anhydride of a dicarboxylic acid to be used commercially. This white solid is an important industrial chemical, especially for the large-scale production of plasticizers for plastics. In 2000, the worldwide production volume was estimated to be about 3 million tonnes per year.

In organic chemistry, a nitrile is any organic compound that has a −C≡N functional group. The name of the compound is composed of a base, which includes the carbon of the −C≡N, suffixed with "nitrile", so for example CH3CH2C≡N is called "propionitrile". The prefix cyano- is used interchangeably with the term nitrile in industrial literature. Nitriles are found in many useful compounds, including methyl cyanoacrylate, used in super glue, and nitrile rubber, a nitrile-containing polymer used in latex-free laboratory and medical gloves. Nitrile rubber is also widely used as automotive and other seals since it is resistant to fuels and oils. Organic compounds containing multiple nitrile groups are known as cyanocarbons.

In organic chemistry, the Knoevenagel condensation reaction is a type of chemical reaction named after German chemist Emil Knoevenagel. It is a modification of the aldol condensation.

The Sandmeyer reaction is a chemical reaction used to synthesize aryl halides from aryl diazonium salts using copper salts as reagents or catalysts. It is an example of a radical-nucleophilic aromatic substitution. The Sandmeyer reaction provides a method through which one can perform unique transformations on benzene, such as halogenation, cyanation, trifluoromethylation, and hydroxylation.

The Ullmann condensation or Ullmann-type reaction is the copper-promoted conversion of aryl halides to aryl ethers, aryl thioethers, aryl nitriles, and aryl amines. These reactions are examples of cross-coupling reactions.

<span class="mw-page-title-main">Zeisel determination</span>

The Zeisel determination or Zeisel test is a chemical test for the presence of esters or ethers in a chemical substance.

The Rosenmund reduction is a hydrogenation process in which an acyl chloride is selectively reduced to an aldehyde. The reaction was named after Karl Wilhelm Rosenmund, who first reported it in 1918.

The von Braun amide degradation is the chemical reaction of a monosubstituted amide with phosphorus pentachloride or thionyl chloride to give a nitrile and an organohalide. It is named after Julius Jacob von Braun, who first reported the reaction.

<span class="mw-page-title-main">Organomercury chemistry</span> Group of chemical compounds containing mercury

Organomercury chemistry refers to the study of organometallic compounds that contain mercury. Typically the Hg–C bond is stable toward air and moisture but sensitive to light. Important organomercury compounds are the methylmercury(II) cation, CH3Hg+; ethylmercury(II) cation, C2H5Hg+; dimethylmercury, (CH3)2Hg, diethylmercury and merbromin ("Mercurochrome"). Thiomersal is used as a preservative for vaccines and intravenous drugs.

<span class="mw-page-title-main">Hofmann–Martius rearrangement</span>

The Hofmann–Martius rearrangement in organic chemistry is a rearrangement reaction converting an N-alkylated aniline to the corresponding ortho and / or para aryl-alkylated aniline. The reaction requires heat, and the catalyst is an acid like hydrochloric acid.

<span class="mw-page-title-main">Wolffenstein–Böters reaction</span> Organic reaction converting benzene to picric acid

The Wolffenstein–Böters reaction is an organic reaction converting benzene to picric acid by a mixture of aqueous nitric acid and mercury(II) nitrate.

Stephen aldehyde synthesis, a named reaction in chemistry, was invented by Henry Stephen (OBE/MBE). This reaction involves the preparation of aldehydes (R-CHO) from nitriles (R-CN) using tin(II) chloride (SnCl2), hydrochloric acid (HCl) and quenching the resulting iminium salt ([R-CH=NH2]+Cl) with water (H2O). During the synthesis, ammonium chloride is also produced.

The Mumm rearrangement is an organic reaction and a rearrangement reaction. It describes a 1,3(O-N) acyl transfer of an acyl imidate or isoimide group to an imide.

The Schotten–Baumann reaction is a method to synthesize amides from amines and acid chlorides:

The Hoesch reaction or Houben–Hoesch reaction is an organic reaction in which a nitrile reacts with an arene compound to form an aryl ketone. The reaction is a type of Friedel-Crafts acylation with hydrogen chloride and a Lewis acid catalyst.

<span class="mw-page-title-main">Carboximidate</span>

Carboximidates are organic compounds, which can be thought of as esters formed between a imidic acid and an alcohol, with the general formula R-C(=NR')OR".

<span class="mw-page-title-main">Isothiouronium</span>

In organic chemistry, isothiouronium is a functional group with the formula [RSC(NH2)2]+ (R = alkyl, aryl) and is the acid salt of isothiourea. The H centres can also be replaced by alkyl and aryl. Structurally, these cations resemble guanidinium cations. The CN2S core is planar and the C–N bonds are short.

The Buchner–Curtius–Schlotterbeck reaction is the reaction of aldehydes or ketones with aliphatic diazoalkanes to form homologated ketones. It was first described by Eduard Buchner and Theodor Curtius in 1885 and later by Fritz Schlotterbeck in 1907. Two German chemists also preceded Schlotterbeck in discovery of the reaction, Hans von Pechmann in 1895 and Viktor Meyer in 1905. The reaction has since been extended to the synthesis of β-keto esters from the condensation between aldehydes and diazo esters. The general reaction scheme is as follows:

<span class="mw-page-title-main">Imidoyl chloride</span>

Imidoyl chlorides are organic compounds that contain the functional group RC(NR')Cl. A double bond exist between the R'N and the carbon centre. These compounds are analogues of acyl chloride. Imidoyl chlorides tend to be highly reactive and are more commonly found as intermediates in a wide variety of synthetic procedures. Such procedures include Gattermann aldehyde synthesis, Houben-Hoesch ketone synthesis, and the Beckmann rearrangement. Their chemistry is related to that of enamines and their tautomers when the α hydrogen is next to the C=N bond. Many chlorinated N-heterocycles are formally imidoyl chlorides, e.g. 2-chloropyridine, 2, 4, and 6-chloropyrimidines.

In chemistry imidines are a rare functional group, being the nitrogen analogues of anhydrides and imides. They were first reported by Adolf Pinner in 1883, but did not see significant investigation until the 1950s, when Patrick Linstead and John Arthur Elvidge developed a number of compounds.

References

  1. "Pinner Reaction". Comprehensive Organic Name Reactions and Reagents (504): 2237–2240. 2010. doi:10.1002/9780470638859.conrr504. ISBN   9780470638859.
  2. A. Pinner, F. Klein; Klein (1877). "Umwandlung der Nitrile in Imide". Berichte der deutschen chemischen Gesellschaft . 10 (2): 1889–1897. doi:10.1002/cber.187701002154.
  3. A. Pinner, Fr. Klein; Klein (1878). "Umwandlung der Nitrile in Imide". Berichte der deutschen chemischen Gesellschaft . 11 (2): 1475–1487. doi:10.1002/cber.18780110258.
  4. A. Pinner (1883). "Ueber die Umwandlung der Nitrile in Imide". Berichte der deutschen chemischen Gesellschaft . 16 (2): 1643–1655. doi:10.1002/cber.18830160235.
  5. Roger, R.; Neilson, D. G. (1961). "The Chemistry of Imidates". Chem. Rev. 61 (2): 179–211. doi:10.1021/cr60210a003.
  6. Adams, Roger; Thal, A. F. (1922). "Ethyl Phenylacetate". Organic Syntheses . 2: 27. doi:10.15227/orgsyn.002.0027.
  7. Elvidge, J. A.; Linstead, R. P. (1954). "Heterocyclic imines and amines. Part III. Succinimidine". Journal of the Chemical Society (Resumed): 442. doi:10.1039/JR9540000442.
  8. DeWolfe, Robert H. (1970). Carboxylic Ortho Acid Derivatives. Organic Chemistry. Vol. 14. New York, NY: Academic Press. p. 5. LCCN   70-84226.
  9. Schaefer, F. C.; Peters, G. A. (1961). "Base-Catalyzed Reaction of Nitriles with Alcohols. A Convenient Route to Imidates and Amidine Salts". Journal of Organic Chemistry . 26 (2): 412. doi:10.1021/jo01061a034.