Pyrophosphoryl chloride

Preparation of 6-azacytidine-5 -phosphate by direct phosphorylation with cyanoethylphosphate was not successful. The substance could be prepared, however, on ammonia treatment of 4-thio-6-azauridine-5 -phosphate which was obtained by phosphorylation of 2, 3 -isopropyl-iden-4 thio-6-azauridine with pyrophosphoryl chloride. From mor-pholidate of 6-azacytidine-5 -phosphate, 6-azacytidine-5 -diphosphate was prepared by the action of phosphoric acid. ... 

There are some means for synthesis of defined primary or secondary esters. Monoester salts of phosphoric acid, for instance, are prepared by addition of alcohol or ethoxylated alcohol, alkali fluoride, and pyrophosphoryl chloride (C12P0)20 in a molar ratio of 0.9-1.5 0.05-1 1.0 at -50 to +10°C and hydrolysis of the Cl-containing intermediates with base. Thus, 32.3 g (C12P0)20 was treated at -50°C with 23.9 g lauryl alcohol in the presence of 0.7 g KF and the mixture was slowly warmed to room temperature and hydrolyzed with H20 and 40% NaOH to give 83% sodium monolauryl phosphate. The monoester salts showed comparable or better washing and foaming efficiency than a commercial product [12]. 

Phosphorylation of cholesterol followed by the normal hydrolytic work-up gives the phosphate monoester, not the symmetrical pyrophosphate diester as previously claimed. Cholesteryl phosphorodichloridate and some related steroidal phosphorodichloridates have been prepared from the action of pyrophosphoryl chloride on the appropriate alcohol ... 

General preparative procedures for the preparation of A -alkyl phos-phoramidic dichlorides (10) and A TV -dialkyl phosphorodiamidic chlorides (11) from the appropriate amine and phosphoryl chloride have been described. With weakly basic amines, pyrophosphoryl chloride was... 

A. Geuther and A. Michaelis 7 prepared pyrophosphoryl chloride, PaO, by the action of nitrogen trioxide or peroxide on well-cooled phosphorus trichloride—... 

As part of a programme designed to produce compounds with axial chirality, double Bischler-Napieralski reactions were carried out with oxamide derivatives of co-arylalkylamines. Thus, treatment of the oxamide derived from 3,4-dimethoxy- P -pheny lethylamine with pyrophosphoryl chloride in acetonitrile gave 1 in 84% yield, as expected. An attempt was then made to extend this double cyclisation protocol to the oxamide derived from 2-(3-methoxyphenoxy)ethylamine. Reaction of this latter compound under the same conditions used for the formation of 1, however, gave 2 in 81% yield instead of the expected product of a double Bischler-Napieralski reaction. 

Hydrolysis leads to the same final products as are formed in the hydrolysis of POCI3. Pyrophosphoryl chloride also acts in a similar way with organic compounds containing the hydroxyl group giving, e.g., ethyl esters of phosphoric and chlorophosphoric acids. 

The corresponding acid chloride is pyrophosphoryl chloride (q.v.). When this is treated with water it gives orthophosphoric acid, but when water vapour acts on a solution of the chloride in carbon disulphide some pyrophosphoric acid is produced. 

Aromatization of Rings.—Phosphorylation of prednisolone (269) at C-21 with pyrophosphoryl chloride is accompanied by a novel fragmentation with rearrangement to give the highly toxic 9,10-seco-c-nor-aldehyde (270) as its 3,21-diphosphate. Simpler analogues, including either the 11 (3 - or the 11 a -hydroxy-1,4-dien-3-one structure, suffered the same reaction.221... 

Evaporate the excess of phosphoryl chloride, which may be recovered for reuse in the same reaction, using a rotary evaporator. Kugelrohr distil the residual liquid to give pyrophosphoryl chloride 51 as a colourless liquid, b.p. 60-65°C at 0.1 mmHg, 7.36 g (49%). 

The main agent used for the conversion of oxopurine into chloropurines is phosphoryl chloride, either alone or with added water (which may produce pyrophosphoryl chloride), phosphorus pentachloride, or with bases, usually tertiary amines and especially W,W-dimethyl- or diethyl-aniline. The use of bases, especially aliphatic amines, may however lead to introduction of dialkyamino groups into the purine or formation of other byproducts (74RCR1089). Other reagents which have been used include (a) thionyl chloride in DMF (Vilsmeier-Haak reagents) which converts 2, 3, 5 -tri-0-benzoylinosine into the 6-chloropurine nucleoside (64CPB639) and (b) chloromethylenedimethylammonium chloride in chloroform. 

Attempts to perform the phosphorylation step with either pyrophosphoryl chloride or 2-cyanoethyl phosphate failed. ... 

Downie, I. M., Earle, M. J., Heaney, H., Shuhaibar, K. F. Vilsmeier formylation and glyoxylation reactions of nucleophilic aromatic compounds using pyrophosphoryl chloride. Tefra/jedrorr 1993,49,4015-4034. 

Oxo-4//-l-benzopyran 3-carboxaldehyde (Use of Pyrophosphoryl Chloride) 2-Bromocyclohex-l-ene-l-carboxaldehyde (Use of PBr to Produce a 2-Bromoenal)... 

Oxo-4H-l-benzopyran-3-carboxaldehyde (Use of Pyrophosphoryl Chloride). To a stirred solution of o-hydroxyacetophenone (25 g, 0.184 mol) in 80 mL of DMF, 80 mL of (Cl2P0)20 was added dropwise at —20° during about 10 minutes. The mixture was stirred at room temperature for 13 hours, and decomposed by ice-water. The resulting precipitate was collected by filtration, washed with H2O and then EtOH, and recrystallized from acetone to afford the benzopyrancarboxaldehyde (19.6 g, 61%) as colorless crystals, mp 152-153° (lit. 152°). From the ethanol washings a small amount (430 mg) of tranr.A (2-hydroxybenzoyl) 2-(4-oxo-4//-l-benzopyran-3-yl)ethylene, mp 177-179° (from acetone) was isolated. 

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