Portal:Organic chemistry

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Main page   Functional groups   Organic reactions  

The Organic chemistry Portal

Methane, CH4; the line-angle structural formula shows four carbon-hydrogen single bonds (σ, in black), and the typical 3D shape of tetrahedral molecules, with ~109° interior bond angles (in dashed-green).

Organic chemistry is the chemistry subdiscipline for the scientific study of structure, properties, and reactions of organic compounds and organic materials (materials that contain carbon atoms). Study of structure determines their chemical composition and formula. Study of properties includes physical and chemical properties, and evaluation of chemical reactivity to understand their behavior. The study of organic reactions includes the chemical synthesis of natural products, drugs, and polymers, and study of individual organic molecules in the laboratory and via theoretical (in silico) study.

The range of chemicals studied in organic chemistry include hydrocarbons (compounds containing only carbon and hydrogen), as well as compounds based on carbon, but also containing other elements, especially oxygen, nitrogen, sulfur, phosphorus (included in many biochemicals) and the halogens.

In the modern era, the range extends further into the periodic table, with main group elements, including:

In addition, contemporary research focuses on organic chemistry involving other organometallics including the lanthanides, but especially the transition metals zinc, copper, palladium, nickel, cobalt, titanium and chromium.

To be supplied
Line-angle representation
To be supplied
Ball-and-stick representation
To be supplied
Space-filling representation
Three representations of an organic compound, 5α-Dihydroprogesterone (5α-DHP), a steroid hormone. For molecules showing color, the carbon atoms are in black, hydrogens in gray, and oxygens in red. In the line angle representation, carbon atoms are implied at every terminus of a line and vertex of multiple lines, and hydrogen atoms are implied to fill the remaining needed valences (up to 4).

Organic compounds form the basis of all earthly life and constitute the majority of known chemicals. The bonding patterns of carbon, with its valence of four—formal single, double, and triple bonds, plus structures with delocalized electrons—make the array of organic compounds structurally diverse, and their range of applications enormous. They form the basis of, or are constituents of, many commercial products including pharmaceuticals; petrochemicals and agrichemicals, and products made from them including lubricants, solvents; plastics; fuels and explosives. The study of organic chemistry overlaps organometallic chemistry and biochemistry, but also with medicinal chemistry, polymer chemistry, and materials science.

Selected article

The aldol reaction is an important carbon-carbon bond formation reaction in organic chemistry. In its usual form, it involves the nucleophilic addition of a ketone enolate to an aldehyde to form a β-hydroxy ketone, or "aldol" (aldehyde + alcohol), a structural unit found in many naturally occurring molecules and pharmaceuticals.

Typicalaldol2.gif

Sometimes, the aldol addition product loses a molecule of water during the reaction to form an α,β-unsaturated ketone. This is called an aldol condensation. The aldol reaction was discovered independently by Charles-Adolphe Wurtz and by Alexander Porfyrevich Borodin in 1872. Borodin observed the aldol dimerization of 3-hydroxybutanal from acetaldehyde under acidic conditions. The aldol reaction is used widely in the large scale production of commodity chemicals such as pentaerythritol and in the pharmaceutical industry for the synthesis of optically pure drugs. For example, Pfizer's initial route to the heart disease drug Lipitor (INN: atorvastatin), approved in 1996, employed two aldol reactions, allowing access to multigram-scale quantities of the drug.

The aldol structural motif is especially common in polyketides, a class of natural products from which many pharmaceuticals are derived, including the potent immunosuppressant FK506, the tetracycline antibiotics, and the antifungal agent amphotericin B. Extensive research on the aldol reaction has produced highly efficient methods which enable the otherwise challenging synthesis of many polyketides in the laboratory.

Selected image

TaxolTotalSynthesisColor.png

Paclitaxel is an important drug used for the treatment of cancer. Its complex structure provided a challenging target for its total synthesis by the Nicolaou group. The colors indicate the approach they used.

Selected reaction

The Wittig reaction is a chemical reaction of an aldehyde or ketone with a triphenyl phosphonium ylide (often called a Wittig reagent) to give an alkene and triphenylphosphine oxide.

Wittig reaction

The Wittig reaction was discovered in 1954 by Georg Wittig, for which he was awarded the Nobel Prize in Chemistry in 1979. It is widely used in organic synthesis for the preparation of alkenes. It should not be confused with the Wittig rearrangement.

Wittig reactions are most commonly used to couple aldehydes and ketones to singly substituted phosphine ylides. With simple ylides this results in almost exclusively the Z-alkene product. In order to obtain the E-alkene, the Schlosser modification of the Wittig reaction can be performed.

WikiProjects

Selected Biography

Elias James Corey (born July 12, 1928) is a renowned American organic chemist. In 1990 he won the Nobel Prize in Chemistry "for his development of the theory and methodology of organic synthesis", specifically retrosynthetic analysis.[1][2] Regarded by many as one of the greatest living chemists, he has developed numerous synthetic reagents, methodologies, and has advanced the science of organic synthesis considerably. He was awarded the Japan Prize in 1989.

He was born "William" to Christian Lebanese immigrants in Methuen, Massachusetts, 30 miles north of Boston. His mother changed his name to "Elias" to honor his father who died eighteen months after the birth of his son. His widowed mother, brother, two sisters and an aunt and uncle all lived together in a spacious house- struggling through the depression. He attended Catholic elementary school and Lawrence public High School.[1]

Categories

Organic chemistry Resources

organic nomenclature
Organic reactions

Lists

Organic chemistry Topics

Organic compounds

Organic reactions

Functional Groups

Organic Reactions

According to the Reaction's Mechanism
  1. electrophilic addition or EA
  2. nucleophilic addition or NA
  3. radical addition or RA
  1. nucleophilic aliphatic substitution with SN1, SN2 and SNi reaction mechanisms
  2. nucleophilic aromatic substitution or NAS
  3. nucleophilic acyl substitution
  4. electrophilic substitution or ES
  5. electrophilic aromatic substitution or EAS
  6. radical substitution or RS
  1. 1,2-rearrangements
  2. pericyclic reactions
  3. metathesis

Related portals

{{{title}}}

The following Wikimedia Foundation sister projects provide more on this subject:

Wikibooks
Books

Commons
Media

Wikinews 
News

Wikiquote 
Quotations

Wikisource 
Texts

Wikiversity
Learning resources

Wiktionary 
Definitions

Wikidata 
Database

References

  1. ^ E. J. Corey, X-M. Cheng, The Logic of Chemical Synthesis, Wiley, New York, 1995, ISBN 0-471-11594-0.
  2. ^ "The Logic of Chemical Synthesis: Multistep Synthesis of Complex Carbogenic Molecules (Nobel Lecture)" E.J. Corey, Angew. Chem. Int. Ed. Engl. 1991, 30, 455.