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Phosphines
Organophosphines are organophosphorus compounds with the formula PR''n''H3−''n'', where R is an organic substituent. These compounds can be classified according to the value of ''n'': primary phosphines (''n'' = 1), secondary phosphines (''n'' = 2), tertiary phosphines (''n'' = 3). All adopt pyramidal structures. Organophosphines are generally colorless, lipophilic liquids or solids. The parent of the organophosphines is phosphine (PH3). Annette Schier and Hubert Schmidbaur"P-Donor Ligands" in Encyclopedia of Inorganic Chemistry 2006, Wiley-VCH, Weinheim. 1° vs 2° vs 3° phosphines Organophophines are classified according to the number of organic substituents. Primary phosphines Primary (1°) phosphines, with the formula RPH2, in principle are derived by alkylation of phosphine. Some simple alkyl derivatives such as methylphosphine (CH3PH2) can be prepared by alkylation of phosphine in the presence of base: : (M = Li, Na, K) A more common syn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrophosphination
Hydrophosphination is the insertion of a double bond into a phosphorus-hydrogen bond. Often the hydrophosphination makes phosphorus-carbon bonds by addition of P-H bonds to carbon-carbon multiple bonds, but the reaction is probably most useful in reactions of phosphine with formaldehyde, a form of hydroxymethylation. 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). Hydroxyalkylation Although most of this article concerns addition of P-H bonds to alkenes, an important variant is the hydrophosphination of formaldehyde. Tetrakis(hydroxymethyl)phosphonium chloride (THPC) is prepared as follows from phosphine: :PH3 + 4 H2C=O + HCl → [P(CH2OH)4]Cl It is a white water-soluble salt with applications as a precursor to fire-retardant materials and as a microbiocide in co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
