Phosphine oxide Phosphine oxides are phosphorus compounds with the formula OPX3 . When X = alkyl or aryl , these are organophosphine oxides. Triphenylphosphine oxide is an example. An inorganic phosphine oxide is phosphoryl chloride . Such compounds are thermally stable, decomposing only above 450 °C. Phosphoryl refers to a functional group drawn with a phosphorus-oxygen double bond .Phosphine oxides feature tetrahedral phosphorus centers. The P-O bond is short and polar . According to molecular orbital theory , the short P–O bond is attributed to the donation of the lone pair electrons from oxygen p-orbitals to the antibonding phosphorus-carbon bonds; This proposal, which is supported by ab initio calculations, has gained consensus in the chemistry community. The nature of the P–O bond was once hotly debated. Some discussions invoked a role for phosphorus-centered d-orbitals in bonding, but this analysis is not supported by computational analyses. In terms of simple Lewis structure , the bond is more accurately represented as a dative bond , as is currently used to depict an amine oxide .Syntheses Phosphine oxides are generated as a by-product of the Wittig reaction: Another route to phosphine oxides is the thermolysis of phosphonium hydroxides: In the laboratory, phosphine oxides are usually generated by the oxidation , often accidentally, of tertiary phosphines: Basic phosphines, such as trialkyl derivatives, are prone to this reaction. The hydrolysis of phosphorus dihalides also affords the oxide: A special nonoxidative route is applicable secondary phosphine oxides, which arise by the hydrolysis of the chlorophosphine. An example is the hydrolysis of chlorodiphenylphosphine to give diphenylphosphine oxide:Deoxygenation The deoxygenation of phosphine oxides has been extensively developed. Trichlorosilane is a standard laboratory method. Industrial routes use phosgene or equivalent reagents, which produce chlorotriphenylphosphonium chloride, which is separately reduced. For chiral phosphine oxides, deoxygenation can proceed with retention or inversion of configuration . Classically, inversion is favored by a combination of trichlorosilane and triethylamine whereas in the absence of the Lewis base , the reaction proceeds with retention. The popularity of this method is partly attributable to the availability of inexpensive trichlorosilane. Instead of HSiCl3 , other perchloropolysilanes, e.g. hexachlorodisilane , can also be used. In comparison, using the reaction of the corresponding phosphine oxides with perchloropolysilanes such as Si 2 Cl6 or Si3 Cl8 in benzene or chloroform, phosphines can be prepared in higher yields. Deoxygenation has been effected with boranes and alanes.Use Phosphine oxides are ligands in various applications of homogeneous catalysis . In coordination chemistry , they are known to have labilizing effects to CO ligands cis to it in organometallic reactions . The cis effect describes this process.Parent compound The parent compound phosphine oxide is unstable. It has been detected with mass spectrometry as a reaction product of oxygen and phosphine, by means of FT-IR in a phosphine-ozone reaction and in matrix isolation with a reaction of phosphine, vanadium oxytrichloride and chromyl chloride . It has also been reported relatively stable in a water-ethanol solution by electrochemical oxidation of white phosphorus , where it slowly disproportionates into phosphine and hypophosphorous acid . Secondary phosphine oxides are tautomers of phosphinous acids . Phosphine oxide is reported as an intermediate in the room-temperature polymerization of phosphine and nitric oxide to solid Px Hy .
Popular articles Javier Milei - Argentine libertarian economist, author, radio conductor and public speaker sympathetic to the Austrian School of economic thought. He became widely known for his regular ...Jimmy Carter - American politician, philanthropist, and former farmer who served as the 39th president of the United States from 1977 to 1981. A member of the Democratic Party, he previ...UEFA Euro 2024 - The 2024 UEFA European Football Championship , commonly referred to as UEFA Euro 2024 or simply Euro 2024 , will be the 17th edition of the UEFA European Championship, the quadrennial internationa...Argentina - country located mostly in the southern half of South America. Sharing the bulk of the Southern Cone with Chile to the west, the country is also b...Sam Altman - American entrepreneur, investor, programmer, and blogger. He is the former president of Y Combinator and now the CEO of OpenAI. Early life and education. ...Rosalynn Carter - American who served as First Lady of the United States from 1977 to 1981 as the wife of President Jimmy Carter. For decades, she has been a leading advocate for numerou...Next Argentine presidential election - Next Argentine presidential election - presidential election in Argentina....Popular movies The Hunger Games (film) - 2012 American dystopian action thriller science fiction-adventure film directed by Gary Ross and based on Suzanne Collins’s 2008 novel of the same name. It is the first insta...untitled Captain Marvel sequel - part of Marvel Cinematic Universe....Killers of the Flower Moon (film project) - Killers of the Flower Moon - film project in United States of America. It was presented as drama, detective fiction, thriller. The film project starred Leonardo Dicaprio, Robert De Niro. Director of...Five Nights at Freddy's (film) - Five Nights at Freddy's - film published in 2017 in United States of America. Scenarist of the film - Scott Cawthon....Popular video games Minecraft - sandbox video game developed by Mojang Studios. Created by Markus "Notch" Persson in the Java programming language and released as a public alpha for personal computers in 2...Grand Theft Auto V - 2013 action-adventure game developed by Rockstar North and published by Rockstar Games. It is the first main entry in the Grand Theft Auto series since 2008's Grand Theft ...Roblox - online game platform and game creation system that allows users to program games and play games created by other users. Founded by David Baszucki and Erik Cassel in 2004 and released in...Baldur's Gate III - upcoming role-playing video game developed and published by Larian Studios for Microsoft Windows and the Stadia streaming service. It is the third main game in the Baldur's ...Alan Wake - action-adventure video game developed by Remedy Entertainment and published by Microsoft Studios, released for the Xbox 360 and Microsoft Windows. The story follows best-selling thri...Fortnite - online video game developed by Epic Games and released in 2017. It is available in three distinct game mode versions that otherwise share the same general gameplay and game engine: ...Super Mario RPG - is a role-playing video game developed by Square and published by Nintendo for the Super Nintendo Entertainment System in 1996. It was directed by Yoshihiko Maekawa and Chihiro Fujioka and produced by...Popular books Book of Revelation - The Book of Revelation is the final book of the New Testament, and consequently is also the final book of the Christian Bible. Its title is derived from the first word of the Koine Greek text: apok...Book of Genesis - account of the creation of the world, the early history of humanity, Israel's ancestors and the origins...Gospel of Matthew - The Gospel According to Matthew is the first book of the New Testament and one of the three synoptic gospels. It tells how Israel's Messiah, rejected and executed in Israel, pronounces judgement on ...Michelin Guide - Michelin Guides are a series of guide books published by the French tyre company Michelin for more than a century. The term normally refers to the annually published Michelin Red Guide , the oldest...Psalms - The Book of Psalms , commonly referred to simply as Psalms , the Psalter or "the Psalms", is the first book of the Ketuvim , the third section of the Hebrew Bible, and thus a book of th...Ecclesiastes - Ecclesiastes is one of 24 books of the Tanakh , where it is classified as one of the Ketuvim . Originally written c. 450–200 BCE, it is also among the canonical Wisdom literature of the Old Tes...The 48 Laws of Power - non-fiction book by American author Robert Greene. The book...Popular television series The Crown (TV series) - historical drama web television series about the reign of Queen Elizabeth II, created and principally written by Peter Morgan, and produced by Left Bank Pictures and Sony Pictures Tel...Friends - American sitcom television series, created by David Crane and Marta Kauffman, which aired on NBC from September 22, 1994, to May 6, 2004, lasting ten seasons. With an ensemble cast sta...Young Sheldon - spin-off prequel to The Big Bang Theory and begins with the character Sheldon...Modern Family - American television mockumentary family sitcom created by Christopher Lloyd and Steven Levitan for the American Broadcasting Company. It ran for eleven seasons, from September 23...Loki (TV series) - upcoming American web television miniseries created for Disney+ by Michael Waldron, based on the Marvel Comics character of the same name. It is set in the Marvel Cinematic Universe, shar...Game of Thrones - American fantasy drama television series created by David Benioff and D. B. Weiss for HBO. It...Shameless (American TV series) - American comedy-drama television series developed by John Wells which debuted on Showtime on January 9, 2011. It...
OWIKI.org . Text is available under the Creative Commons Attribution-ShareAlike License.