AcetalIn organic chemistry, an acetal is a functional group with the connectivity . Here, the R groups can be organic fragments (a carbon atom, with arbitrary other atoms attached to that) or hydrogen, while the R' groups must be organic fragments not hydrogen. The two R' groups can be equivalent to each other (a "symmetric acetal") or not (a "mixed acetal"). Acetals are formed from and convertible to aldehydes or ketones and have the same oxidation state at the central carbon, but have substantially different chemical stability and reactivity as compared to the analogous carbonyl compounds.
KetoneIn organic chemistry, a ketone ˈkiːtoʊn is a functional group with the structure , where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group (which contains a carbon-oxygen double bond C=O). The simplest ketone is acetone (where R and R' is methyl), with the formula . 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.
Total synthesisTotal synthesis is the complete chemical synthesis of a complex molecule, often a natural product, from simple, commercially-available precursors. It usually refers to a process not involving the aid of biological processes, which distinguishes it from semisynthesis. Syntheses may sometimes conclude at a precursor with further known synthetic pathways to a target molecule, in which case it is known as a formal synthesis. Total synthesis target molecules can be natural products, medicinally-important active ingredients, known intermediates, or molecules of theoretical interest.
AldolIn organic chemistry, an aldol describes a structural motif consisting of a 3-hydroxy ketone or 3-hydroxyaldehyde. An aldol consisting of a 3-hydroxy ketone is called a β-hydroxy ketone, and an aldol consisting of a 3-hydroxy aldehyde is called a β-hydroxy aldehyde. The term "aldol" may refer to 3-hydroxybutanal. Aldols are usually the product of aldol addition, i.e. the condensation of two aldehydes. Stereoselective syntheses of aldols is an active area of asymmetric synthesis.
Heterocyclic compoundA heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different elements as members of its ring(s). Heterocyclic organic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of organic heterocycles. Examples of heterocyclic compounds include all of the nucleic acids, the majority of drugs, most biomass (cellulose and related materials), and many natural and synthetic dyes. More than half of known compounds are heterocycles.
Cyclic compoundA cyclic compound (or ring compound) is a term for a compound in the field of chemistry in which one or more series of atoms in the compound is connected to form a ring. Rings may vary in size from three to many atoms, and include examples where all the atoms are carbon (i.e., are carbocycles), none of the atoms are carbon (inorganic cyclic compounds), or where both carbon and non-carbon atoms are present (heterocyclic compounds with rings containing both carbon and non-carbon).
Aldol reactionThe aldol reaction (aldol addition) is a reaction that combines two carbonyl compounds (aldehydes or ketones) to form a new β-hydroxy carbonyl compound. These products are known as aldols, from the aldehyde + alcohol, a structural motif seen in many of the products. The use of aldehyde in the name comes from its discovery history, where aldehydes were first used in the reaction and not ketones. Aldol structural units are found in many important molecules, whether naturally occurring or synthetic.
Ring (chemistry)In chemistry, a ring is an ambiguous term referring either to a simple cycle of atoms and bonds in a molecule or to a connected set of atoms and bonds in which every atom and bond is a member of a cycle (also called a ring system). A ring system that is a simple cycle is called a monocycle or simple ring, and one that is not a simple cycle is called a polycycle or polycyclic ring system. A simple ring contains the same number of sigma bonds as atoms, and a polycyclic ring system contains more sigma bonds than atoms.
Carbonyl reductionIn organic chemistry, carbonyl reduction is the organic reduction of any carbonyl group by a reducing agent. Typical carbonyl compounds are ketones, aldehydes, carboxylic acids, esters, and acid halides. Carboxylic acids, esters, and acid halides can be reduced to either aldehydes or a step further to primary alcohols, depending on the strength of the reducing agent; aldehydes and ketones can be reduced respectively to primary and secondary alcohols. In deoxygenation, the alcohol can be further reduced and removed altogether.
Α-Halo ketoneIn organic chemistry, an α-halo ketone is a functional group consisting of a ketone group or more generally a carbonyl group with an α-halogen substituent. α-Halo ketones are alkylating agents. Prominent α-halo ketones include phenacyl bromide and chloroacetone. The general structure is RR′C(X)C(=O)R where R is an alkyl or aryl residue and X any one of the halogens. The preferred conformation of a halo ketone is that of a cisoid with the halogen and carbonyl sharing the same plane as the steric hindrance with the carbonyl alkyl group is generally larger.
HemiacetalA hemiacetal or a hemiketal has the general formula R1R2C(OH)OR, where R1 or R2 is hydrogen or an organic substituent. They generally result from the addition of an alcohol to an aldehyde or a ketone, although the latter are sometimes called hemiketals. Most sugars are hemiacetals. According to the IUPAC definition, in R1R2C(OH)OR R1 and R2 may or may not be a hydrogen. In a hemiketal, neither R-group can be a hydrogen. Hemiketals are regarded as hemiacetals where none of the R-groups are H, and are therefore a subclass of the hemiacetals.
Organolithium reagentIn organometallic chemistry, organolithium reagents are chemical compounds that contain carbon–lithium (C–Li) bonds. These reagents are important in organic synthesis, and are frequently used to transfer the organic group or the lithium atom to the substrates in synthetic steps, through nucleophilic addition or simple deprotonation. Organolithium reagents are used in industry as an initiator for anionic polymerization, which leads to the production of various elastomers.
Aldol condensationAn aldol condensation is a condensation reaction in organic chemistry in which two carbonyl moieties (of aldehydes or ketones) react to form a β-hydroxyaldehyde or β-hydroxyketone (an aldol reaction), and this is then followed by dehydration to give a conjugated enone. The overall reaction equation is as follows (where the Rs can be H) Aldol condensations are important in organic synthesis and biochemistry as ways to form carbon–carbon bonds.
AldehydeIn organic chemistry, an aldehyde (ˈældᵻhaɪd) is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred to as an aldehyde but can also be classified as a formyl group. Aldehydes are a common motif in many chemicals important in technology and biology. Aldehyde molecules have a central carbon atom that is connected by a double bond to oxygen, a single bond to hydrogen and another single bond to a third substituent, which is carbon or, in the case of formaldehyde, hydrogen.
Organozinc chemistryOrganozinc chemistry is the study of the physical properties, synthesis, and reactions of organozinc compounds, which are organometallic compounds that contain carbon (C) to zinc (Zn) chemical bonds. Organozinc compounds were among the first organometallic compounds made. They are less reactive than many other analogous organometallic reagents, such as Grignard and organolithium reagents. In 1848 Edward Frankland prepared the first organozinc compound, diethylzinc, by heating ethyl iodide in the presence of zinc metal.
Organocopper chemistryOrganocopper chemistry is the study of the physical properties, reactions, and synthesis of organocopper compounds, which are organometallic compounds containing a carbon to copper chemical bond. They are reagents in organic chemistry. The first organocopper compound, the explosive copper(I) acetylide (), was synthesized by Rudolf Christian Böttger in 1859 by passing acetylene gas through a solution of copper(I) chloride: Organocopper compounds are diverse in structure and reactivity, but almost all are based on copper with anoxidation state of +1, sometimes denoted Cu(I) or .
Chemical synthesisIn chemistry, chemical synthesis (chemical combination) is the artificial execution of chemical reactions to obtain one or several products. This occurs by physical and chemical manipulations usually involving one or more reactions. In modern laboratory uses, the process is reproducible and reliable. A chemical synthesis involves one or more compounds (known as reagents or reactants) that will experience a transformation when subjected to certain conditions. Various reaction types can be applied to formulate a desired product.
Ketone bodiesKetone bodies are water-soluble molecules or compounds that contain the ketone groups produced from fatty acids by the liver (ketogenesis). Ketone bodies are readily transported into tissues outside the liver, where they are converted into acetyl-CoA (acetyl-Coenzyme A)—which then enters the citric acid cycle (Krebs cycle) and is oxidized for energy. These liver-derived ketone groups include acetoacetic acid (acetoacetate), beta-hydroxybutyrate, and acetone, a spontaneous breakdown product of acetoacetate (see graphic).
Condensation reactionIn organic chemistry, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. If water is lost, the reaction is also known as a dehydration synthesis. However other molecules can also be lost, such as ammonia, ethanol, acetic acid and hydrogen sulfide. The addition of the two molecules typically proceeds in a step-wise fashion to the addition product, usually in equilibrium, and with loss of a water molecule (hence the name condensation).
Intramolecular reactionIn chemistry, intramolecular describes a process or characteristic limited within the structure of a single molecule, a property or phenomenon limited to the extent of a single molecule. intramolecular hydride transfer (transfer of a hydride ion from one part to another within the same molecule) intramolecular hydrogen bond (a hydrogen bond formed between two functional groups of the same molecule) cyclization of ω-haloalkylamines and alcohols to form the corresponding saturated nitrogen and oxygen heterocycles, respectively (an SN2 reaction within the same molecule) In intramolecular organic reactions, two reaction sites are contained within a single molecule.
