Phosphorine is a heavier element analog of pyridine, containing a phosphorus atom instead of an aza- moiety. It is also called phosphabenzene and belongs to the phosphaalkene class. It is a colorless liquid that is mainly of interest in research.
Phosphorous acid is the compound described by the formula H3PO3. This acid is diprotic, not triprotic as might be suggested by this formula. Phosphorous acid is an intermediate in the preparation of other phosphorus compounds. Organic derivatives of phosphorous acid, compounds with the formula RPO3H2, are called phosphonic acids.
Diphosphene is a type of organophosphorus compound that has a phosphorus–phosphorus double bond, denoted by R-P=P-R'. These compounds are not common but are of theoretical interest. Normally, compounds with the empirical formula RP exist as rings. However, like other multiple bonds between heavy main-group elements, P=P double bonds can be stabilized by a large steric hindrance from the substitutions. The first isolated diphosphene bis(2,4,6-tri-tert-butylphenyl)diphosphene was exemplified by Masaaki Yoshifuji and his coworkers in 1981, in which diphosphene is stabilized by two bulky phenyl group.
In chemistry, a phosphaalkyne is an organophosphorus compound containing a triple bond between phosphorus and carbon with the general formula R-C≡P. Phosphaalkynes are the heavier congeners of nitriles, though, due to the similar electronegativities of phosphorus and carbon, possess reactivity patterns reminiscent of alkynes. Due to their high reactivity, phosphaalkynes are not found naturally on earth, but the simplest phosphaalkyne, phosphaethyne (H-C≡P) has been observed in the interstellar medium.
A phosphorane (IUPAC name: λ5-phosphane) is a functional group in organophosphorus chemistry with pentavalent phosphorus. Phosphoranes have the general formula PR5.
Organophosphorus chemistry is the scientific study of the synthesis and properties of organophosphorus compounds, which are organic compounds containing phosphorus. They are used primarily in pest control as an alternative to chlorinated hydrocarbons that persist in the environment. Some organophosphorus compounds are highly effective insecticides, although some are extremely toxic to humans, including sarin and VX nerve agents.
Phosphole is the organic compound with the chemical formula C
4H
4PH; it is the phosphorus analog of pyrrole. The term phosphole also refers to substituted derivatives of the parent heterocycle. These compounds are of theoretical interest but also serve as ligands for transition metals and as precursors to more complex organophosphorus compounds.
Phenylphosphine is an organophosphorus compound with the chemical formula C6H5PH2. It is the phosphorus analog of aniline. Like other primary phosphines, phenylphosphine has an intense penetrating odor and is highly oxidizable. It is mainly used as a precursor to other organophosphorus compounds. It can function as a ligand in coordination chemistry.
Methylidynephosphane (phosphaethyne) is a chemical compound which was the first phosphaalkyne compound discovered, containing the unusual C≡P carbon-phosphorus triple bond.
Phosphinidenes are low-valent phosphorus compounds analogous to carbenes and nitrenes, having the general structure RP. The "free" form of these compounds is conventionally described as having a singly-coordinated phosphorus atom containing only 6 electrons in its valence level. Most phosphinidenes are highly reactive and short-lived, thereby complicating empirical studies on their chemical properties. In the last few decades, several strategies have been employed to stabilize phosphinidenes, and researchers have developed a number of reagents and systems that can generate and transfer phosphinidenes as reactive intermediates in the synthesis of various organophosphorus compounds.
tert-Butylphosphaacetylene is an organophosphorus compound. Abbreviated t-BuCP, it was the first example of an isolable phosphaalkyne. Prior to its synthesis, the double bond rule had suggested that elements of Period 3 and higher were unable to form double or triple bonds with lighter main group elements because of weak orbital overlap. The synthesis of t-BuCP discredited much of the double bond rule and opened new studies into the formation of unsaturated phosphorus compounds.
Hydrophosphination is the insertion of a carbon-carbon multiple bond into a phosphorus-hydrogen bond forming a new phosphorus-carbon bond. Like other hydrofunctionalizations, the rate and regiochemistry of the insertion reaction is influenced by the catalyst. Catalysts take many forms, but most prevalent are bases and free-radical initiators. Most hydrophosphinations involve reactions of phosphine (PH3).
Phosphirane is the organophosphorus compound with the formula C2H4PH. It is a colorless gas of no commercial value. As the simplest cyclic, saturated organophosphorus compound, phosphirane is the prototype of a family of related compounds that have attracted attention from the research community. Phosphirane was first prepared by reaction of 1,2-dichloroethane with the conjugate base of phosphine. Phosphiranes, that is substituted phosphirene compounds where one or more of the H's are replaced organic substituents, are far more commonly discussed than the parent phosphirane.
Phosphirenium ions are a series of organophosphorus compounds containing unsaturated three-membered ring phosphorus (V) heterocycles and σ*-aromaticity is believed to be present in such molecules. Many of the salts containing phosphirenium ions have been isolated and characterized by NMR spectroscopy and X-ray crystallography.
The phosphaethynolate anion, also referred to as PCO, is the phosphorus-containing analogue of the cyanate anion with the chemical formula [PCO]− or [OCP]−. The anion has a linear geometry and is commonly isolated as a salt. When used as a ligand, the phosphaethynolate anion is ambidentate in nature meaning it forms complexes by coordinating via either the phosphorus or oxygen atoms. This versatile character of the anion has allowed it to be incorporated into many transition metal and actinide complexes but now the focus of the research around phosphaethynolate has turned to utilising the anion as a synthetic building block to organophosphanes.
Intrinsic bond orbitals (IBO) are localized molecular orbitals giving exact and non-empirical representations of wave functions. They are obtained by unitary transformation and form an orthogonal set of orbitals localized on a minimal number of atoms. IBOs present an intuitive and unbiased interpretation of chemical bonding with naturally arising Lewis structures. For this reason IBOs have been successfully employed for the elucidation of molecular structures and electron flow along the intrinsic reaction coordinate (IRC). IBOs have also found application as Wannier functions in the study of solids.
1-Phosphaallenes is are allenes in which the first carbon atom is replaced by phosphorus, resulting in the structure: -P=C=C<.
Pnictogen-substituted tetrahedranes are pnictogen-containing analogues of tetrahedranes with the formula RxCxPn4-x. Computational work has indicated that the incorporation of pnictogens to the tetrahedral core alleviates the ring strain of tetrahedrane. Although theoretical work on pnictogen-substituted tetrahedranes has existed for decades, only the phosphorus-containing species have been synthesized. These species exhibit novel reactivities, most often through ring-opening and polymerization pathways. Phosphatetrahedranes are of interest as new retrons for organophosphorus chemistry. Their strain also make them of interest in the development of energy-dense compounds.
A phosphetene is an unsaturated four-membered organophosphorus heterocycle containing one phosphorus atom. It is a heavier analog of an azetine, or dihydroazete. The first synthesis of a stable, isolable phosphetene was reported in 1985 by Mathey et al. via ring expansion of a phosphirene-metal carbonyl complex. Since then, other synthesis routes for phosphetenes have been developed such as cyclization of phosphabutadienes, [2 + 2] cycloaddition, intramolecular arrangement, addition, and through organometallic intermediates.
Phosphiranes are organic compounds with the phosphirane functional group – a three-membered ring with two atoms of carbon and one atom of phosphorus that has lots of ring angle strain. Phosphiranes are usually synthesized by double substitution reactions or pericyclic pathways. Phosphiranes can also be oxidized into phosphirane oxides, undergo SN2 substitution reactions, or decompose into different units.
