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Phosphonium ion Structure of PH + 4, the parent phosphonium cation. In chemistry, the term phosphonium (more obscurely: phosphinium) describes polyatomic cations with the chemical formula PR + 4 (where R is a hydrogen or an alkyl, aryl, organyl or halogen group). These cations have tetrahedral structures.
Because phosphonium ylides are seldom isolated, the byproduct(s) generated upon deprotonation essentially plays the role of an additive in a Wittig reaction. As a result, the choice of base has a strong influence on the efficiency and, when applicable, the stereochemical outcome of the Wittig reaction.
In contrast to phosphonium ylides used in the Wittig reaction, phosphonate-stabilized carbanions are more nucleophilic but less basic. Likewise, phosphonate-stabilized carbanions can be alkylated. Unlike phosphonium ylides, the dialkylphosphate salt byproduct is easily removed by aqueous extraction. Several reviews have been published.
Tetraphenylphosphonium chloride is the chemical compound with the formula [(C 6 H 5) 4 P]Cl, abbreviated Ph 4 PCl or PPh 4 Cl or [PPh 4]Cl, where Ph stands for phenyl. Tetraphenylphosphonium and especially tetraphenylarsonium salts were formerly of interest in gravimetric analysis of perchlorate and related oxyanions.
Phosphonium iodide is a powerful substitution reagent in organic chemistry; for example, it can convert a pyrilium into a phosphinine via substitution. [3] In 1951, Glenn Halstead Brown found that PH 4 I reacts with acetyl chloride to produce an unknown phosphine derivative, possibly CH 3 C(=PH)PH 2 ·HI. [4]
It is the bromide salt of a phosphonium cation. It is a white salt that is soluble in polar organic solvents. Synthesis and reactions ...
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Tetrakis(hydroxymethyl)phosphonium chloride (THPC) is an organophosphorus compound with the chemical formula [P(CH 2 OH) 4]Cl. It is a white water-soluble salt with applications as a precursor to fire-retardant materials [ 1 ] and as a microbiocide in commercial and industrial water systems.