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Hydrogen sulphide, phosphorylation

The hydrolysis of tervalent phosphorus acid derivatives with two P—C bonds leads to secondary phosphine oxides (50) and with one P—C bond to phosphonus acid derivatives (51). Chlorophosphines react rapidly with water, but aminophosphines, phosphinites and phosphonites often survive a short wash with aqueous NaHC03, an effective way to remove contaminating ammonium salts in the crude products. However, aminophosphines with small substituents, e.g. dimethylaminodimethylphosphine, aryl phosphinites and phosphonites and trimethylsilyl phosphinites and phosphonites are hydrolysed too quickly for such a treatment. The hydrolyses are catalysed by acids (the hydrolyses of phosphinites and phosphonites are also catalysed by OH ) and are much faster than hydrolyses of the corresponding phosphoryl compounds [up to a factor of 10 for acid-catalysed hydrolysis of (MeO)3P compared with (MeO)3P=0 ]. Dialkyl phosphonites are rapidly hydrolysed to the monoalkyl esters (51, X = OR) in weakly acidic water, whereas hydrolyses to phosphonous acids require reflux with strong acid or base, e.g. equation 131 Bis-(dialkylamino) phosphines may also be partially hydrolysed to phosphonous acid amides (51, X = NR2). Tervalent phosphorus acid derivatives with hydrogen sulphide give secondary phosphine sulphides or phosphonodithious acids, e.g. equation 156 . ... [Pg.36]

Pyrrolo[2,l-b]thiazoles (C3NS-C4N).— Pyrrolo[2,l-b]thiazoles have been thioformylated by a novel application of the Vilsmeier reaction. Treatment of the reactants (135) with phosphoryl chloride in DMF produces the Vilsmeier salts (136), which are convertible into the orange or red pyrrolo[2,l-b]thiazole-5-thioaldehydes (137) by thiohydrolysis, using sodium hydrogen sulphide. The isomeric 7-thioaldehydes (138) are similarly... [Pg.643]

The electrical conductivities of soln. of a great many compounds in liquid hydrogen halides have been measured by E. H. Archibald and D. McIntosh. The conductivity is raised considerably by phosphoryl chloride. Sodium sodium sulphide, borate, phosphate, nitrate, thiosulphate, and arsenate chromic anhydride potassium nitrate, hydroxide, chromate, sulphide, bisulphate, and ferro- and ferri- cyanide ammonium fluoride and carbonate j rubidium and caesium chloride magnesium sulphate calcium fluoride ... [Pg.179]

Titanium tetrachloride is an efficient reagent for the conversion of trialkyl phosphites and dialkyl hydrogen phosphonates into dialkyl phosphorochloridates. Imidazolides and dialkyl or diaryl phosphoric acids react with acyl fluorides - benzoyl fluoride and oxalyl difluoride being the reagents of choice - to give quantitative yields of the phosphoryl fluorides. The procedure is adaptable to the preparation of fluorides of carbohydrate phosphates in this field, the reaction between the ceu bohydrate and tris-l//-imidazolylphosphine oxide or sulphide with the replacement of one imidazole... [Pg.113]


See other pages where Hydrogen sulphide, phosphorylation is mentioned: [Pg.814]    [Pg.827]    [Pg.976]    [Pg.1013]    [Pg.1023]    [Pg.1035]    [Pg.1036]    [Pg.1055]    [Pg.1055]    [Pg.1056]    [Pg.1070]    [Pg.1074]    [Pg.123]    [Pg.169]    [Pg.247]    [Pg.247]    [Pg.1015]    [Pg.1017]    [Pg.89]    [Pg.260]    [Pg.303]    [Pg.28]    [Pg.178]   


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Hydrogen sulphide

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