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The general structure of a phosphite ester showing the lone pairs on the P. In organic chemistry, a phosphite ester or organophosphite usually refers to an organophosphorous compound with the formula P(OR) 3. They can be considered as esters of an unobserved tautomer phosphorous acid, H 3 PO 3, with the simplest example being trimethylphosphite ...
Phosphites, sometimes called phosphite esters, have the general structure P(OR) 3 with oxidation state +3. Such species arise from the alcoholysis of phosphorus trichloride: PCl 3 + 3 ROH → P(OR) 3 + 3 HCl. The reaction is general, thus a vast number of such species are known.
Likewise, tripolyphosphoric acid H 5 P 3 O 10 yields at least five anions [H 5−k P 3 O 10] k−, where k ranges from 1 to 5, including tripolyphosphate [P 3 O 10] 5−. Tetrapolyphosphoric acid H 6 P 4 O 13 yields at least six anions, including tetrapolyphosphate [P 4 O 13] 6−, and so on. Note that each extra phosphoric unit adds one extra ...
Esterifications of phosphoric acid with alcohols proceed less readily than the more common carboxylic acid esterifications, with the reactions rarely proceeding much further than the phosphate mono-ester. The reaction requires high temperatures, under which the phosphoric acid can dehydrate to form poly-phosphoric acids.
Solvents are often not used for this reaction, though there is precedent for the improvement of selectivity with its usage. [5] Phosphonites are generally more reactive than phosphite esters. They react to produce phosphinates. Heating is also required for the reaction, but pyrolysis of the ester to an acid is a common side reaction. The poor ...
While nucleophilic acyl substitution reactions can be base-catalyzed, the reaction will not occur if the leaving group is a stronger base than the nucleophile (i.e. the leaving group must have a higher pK a than the nucleophile). Unlike acid-catalyzed processes, both the nucleophile and the leaving group exist as anions under basic conditions.
a strong base; deprotonates ketones and esters to generate enolate derivative Sodium borohydride: a versatile reducing agent; converts ketones and aldehydes to alcohols Sodium chlorite: in organic synthesis, used for the oxidation of aldehydes to carboxylic acids Sodium hydride: a strong base used in organic synthesis Sodium hydroxide
The Abramov reaction is the related conversions of trialkyl to α-hydroxy phosphonates by the addition to carbonyl compounds. In terms of mechanism, the reaction involves attack of the nucleophilic phosphorus atom on the carbonyl carbon. [1] It was named after the Russian chemist Vasilii Semenovich Abramov (1904–1968) in 1957. [2]