Phosphorochloridates cyclic

The alcoholysis of the cyclic phosphate of catechol by alditols can lead, after acid hydrolysis of intermediate, cyclic phosphates, to the selective formation of phosphoric esters of the primary hydroxyl groups in the alditols. Thus, erythritol and D-mannitol afford, after chromatographic purification of the reaction products, their 1-phosphates in yields of 31 and 38%, respectively.217 The method was used to convert riboflavine into riboflavine 5 -phosphate.218 1-Deoxy-1-fluoro-L-glycerol has been converted into the 3-(dibenzyl phosphate) in 54% yield by selective reaction with dibenzyl phosphorochloridate. 219... 

Trialkyl phosphites undergo reaction with molecular halogen via a mechanism reminiscent of the Michaelis-Arbuzov reaction to form the dialkyl phosphorochloridate in good yield (Equation 4.4).7 With cyclic esters, the halogen performing the displacement reaction at carbon remains attached within the molecule. 

If 8-mercaptoadenosine-2, 3/-cyclic phosphate is treated with a phosphateactivating agent, e.g. diphenyl phosphorochloridate or tetraphenyl pyrophosphate, an oligomer is formed in which each phosphate is esterified by the 2 - and 3 -hydroxy-groups of one nucleoside residue and the 5 -hydroxy-group of the next. On... 

To obtain model compounds for the study of inositol phosphates, Kil-gour and Ballou180 treated di-O-isopropylidenepinitol (LXIV) and di-O-isopropylidene-Zeyo-inositol (XXVIII) with diphenyl phosphorochloridate. For the latter, the result was surprising instead of the expected mono-or di-phosphate, a cyclic phosphate (LXXIX) was obtained. In it, the phosphate group is attached to two irans-hydroxyl groups, like the third iso-propylidene group in tri-O-isopropylidene-fevo-inositol (see p. 149). This... 

This chloroformate then either decomposes to give (PhO)2P(0)Cl and COj, or reacts with the starting material to form the corresponding pyrophosphate, (Ph0)jP(0)0P(0)(0Ph) j. Less of the phosphorochloridate is formed in the reaction of phosgene with the cyclic phosphodiester, although the mechanism is believed to follow the same general pathway [1678]. 

The superscripts in the methods column denote the following isotopicaUy labeled nucleotide was made by this procedure nucleotide isolated as the 5 -alkyl or 5 -aryl ester only nucleotide isolated as the 2, 3 -0-isopropylidene acetal only nucleotide isolated as the 2, 3 -0-isopropylidene, 5 -alkyl or 5 -aryl ester derivative only nucleotide isolated as the 2, 3 -di-0-benzoyl, 5 -aryl ester only method involves initial formation of a pyrophosphate derivative by reaction of diphenyl phosphorochloridate with hydrobenzoin cyclic phosphate. 

A versatile method to generate p-ketophosphonates that cannot be generated through the Arbuzov reaction has been developed a-phosphonate enolates of cyclic ketones are obtained through sequential treatment of ketones wiA LDA, diediyl phosphorochloridate and LDA (Scheme Acyclic P-ketophosphonates can also be formed from a-bromo ketones (Scheme 8) and in a similar reaction a-trialkylsilyl enolates can also be obtained (Scheme 9).3 -36 Kuwajima and Takeda employed the reaction of ot-phenylselenylvinyl silyl ethers with lithium and di-methylaminoniq>hthalene (DMAN) to generate ot-silyl enolates (Scheme 10). ... 

A versatile method to generate p-ketophosphonates that cannot be generated through the Arbuzov reaction has been developed a-phosphonate enolates of cyclic ketones are obtained through sequential treatment of ketones with LDA, diethyl phosphorochloridate and LDA (Scheme 7).33-34... 

Arguments have been presented to suggest that the mechanism of catalyzed nucleophilic displacement at a phosphoryl or thiophosphoryl centre may not be as had been previously thought. Thus far, nucleophilic displacements have been thought to involve double Sj 2 displacements involving the catalyst and/or, pentacoordinate intermediates. Measurements of reaction rates and stereochemical changes for a variety of linear and cyclic phosphorochloridates (and also phosphonochloridates and phosphonochloridothioates) in alcoholysis reactions catalyzed by hexamethylphosphorous triamide, pyridine, or N-methylimidazole (the order of increasing reactivity) have been used to question the earlier ideas, and it has now been proposed that the... 

Preparative studies have been reported on the phosphorylation of a series of hydrazines and hydrazones and on the phosphorylation of vicinal diamines with diphenyl phosphorochloridate. The cyclic phosphoramidate esters (12) and (13) may be obtained by treatment of the appropriate acyclic... 

The reaction between the cyclic phosphorochloridate (109) and a strictly equimolar amount of water yields o-phenylene hydrogen phosphate (110) in the presence of excess water, both (109) and (110) afford the acyclic pho.sphate (112). On the other hand, the cyclic esters and amide (111) with one mole of water each yield the corresponding (113)... 

Fig. 4 Mechanisms of epimerization of cyclic phosphorochloridate [33a]. Several modifications of mechanisms A, C and D exist, since (i) the order of recyclization and retention steps may be switched and (ii) initial attack may be apical to endocyclic nitrogen or endocyclic oxygen if apical potentialities are similar (Hail and Inch, 1981). Ring substituents are omitted for clarity.

D-Mannitol reacted with phosphorus trichloride in p-dioxan to give the 1,2 3,4 5,6-tris(phosphorochloridate) and the bis(cyclic phosphite) (45 X which was converted into the l,6-dichloro-l,6-dideoxy-D-mannitol derivative (458) on treatment with chlorine. ... 

Without additional reagents Cyclic phosphorochloridates from cyclic phosphorochloridites... 

A new phosphorylating reagent, dibenzyl phosphorofluoridate, has been introduced. In the presence of caesium fluoride as base it reacts with primary and anomeric hydroxy groups preferentially. Secondary hydroxy groups, e.q.. those of partially protected myo-inositol, can be phosphorylated after deprotection with butyl lithium. 1,2-Di-phosphates were obtained in good to excellent yields by treatment of vicinal diols with diethyl phosphorochloridate and butyl lithium there was no evidence of formation of cyclic phosphates, the predominant products when other bases are used. Q-Glycosylation of phosphonic and phosphinic acids has been achieved by the trichloroacetimidate method examples are given in Scheme 4. ... 

Several other compounds are formed in the reaction such as diesters (R0)2P02H, triesters (RO)3PO and cyclic esters. In order to avoid these side reactions, substituted compounds are now used, particularly diphenyl phosphorochloridate [(CjH50)2POCl], dibenzyl phosphorochloridate [(CfiH.CHiOliPOCllformonoesters, and phenyl phosphorodichloridate (C6HjO-POCl2) for diesters. 

D-Glucose 2-phosphate is formed as decomposition product of uridine diphosphate glucose with cyclic 1,2-glucose phosphate as intermediate . It has been prepared by phosphorylation of r,3,4,6-tetraacetyl-/ D-glucose with diphenyl phosphorochloridate . 

D-Glucose 4,6-cyclic phosphate has been prepared by treatment of a-methyl- or /J-phenyl-D-glucoside with phenyl phosphorochloridate . ... 

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