Thiophosphoryl group

Reactions of the same halogenophosphazenes with ammonia were also described, in which halide-ion displacement took place at the phosphazenyl group rather than at the thiophosphoryl group ... 

Two isomers were expected according to the outside or inside orientation of the thiophosphoryl group. Only one isomer was characterized showing the P=S bond directed outside. The new hemicryptophane 22 presents a molecular cavity large enough to complex a toluene molecule as shown in the solid state structure depicted in Fig. 14. The toluene complex is stabilized through Van der Waals and specific r-interactions. 

Scheme 61 Conversion of the phosphoryl group of the Diels-Alder dimer 195 into the thiophosphoryl group of compound 197...

There are two basic methods by which configurations are assigned to chiral [lsO]thiophosphoryl groups. The first one is the one introduced by Usher, Richardson and Eckstein [31], which is applicable to vicinal hydroxy [180]phosphorothioates when the absolute configurations of the corresponding diastereomeric cyclic phos-phorothioates are known. The principle is illustrated in Equation 8 for sn-glycerol-3-[18 OJphosphorothioate ... 

The stereochemical consequence of [lsO]thiophosphoryl and [l60, nO, lsO]phos-phoryl group transfer catalyzed by seven phosphotransferases were simultaneously determined in the author s laboratory and in the laboratory of J.R. Knowles. The first to be completed was the demonstration of inversion by adenylate kinase however, prior to that glycerokinase, hexokinase and pyruvate kinase had been shown to catalyze [l80]thiophosphoryl group transfer with the same stereochemical consequences, either all with inversion or all with retention. Glycerokinase was later shown to catalyze both [l60, nO, l80]phosphoryl and [l80]thiophosphoryl group... 

Four examples are known of calix[6]arene derivatives which have been used as receptor molecules in potentiometric measuring devices. Calix[6]arene 36 functionalized with six ethylester moieties showed a moderate selectivity for hexylammo-nium ions in the presence of smaller primary alkylammonium ions (logA = —1.0 to — 1.4) in ion-selective electrodes [140]. The same derivative 36 also proved to be sensitive towards Cs ions [141]. CHEMFETs with calix[6]arenes, functionalized with three diethylamido moieties (37) or with three phosphate moieties (38), are selective for guanidinium ions [142]. The fourth example is calix[6]arene 39 functionalized with two thiophosphoryl groups which is selective for Pb " ions... 

The 83IP values of several phosphazinium bromides, e.g., 18, have been studied and show a much smaller variation in chemical shift (6 = 35-38) compared with their free bases (5= 14-20). The complex reactions of iodine with tert-butyl(isopropyl)iodophosphine to produce several tert-butyl(isopropyl)diio-dophosphonium iodides has been followed in solution by P and H NMR spectroscopy. P NMR spectroscopy has also been used in the characterisation of new phosphorus-crown compounds containing the thiophosphoryl group, and cyclophosphazenes and polyphosphazenes. ... 

This observation is consistent with the greater reactivity of the thiophosphoryl group compared to that of the phosphoryl group. Prolonged contact with EtO(EtS)P(0)Me at room temperature, however, also resulted in the formation of the product of Equation (10.48). 

The stereochemical studies in this category, the transfer of a phosphoryl group between two phosphomonoesters, are summarized in Table 3 for those using a thiophosphoryl group and in Table 4 for those using a [160,170,180]-phosphoryl group. 

The approach by use of a thiophosphoryl group was mainly developed in Frey s and Knowles laboratories. Various biophosphates carrying an [180]-thiophosphoryl group were synthesized and subjected to enzymatic reactions. The products were derivatized and analyzed mainly by the mass spectral method, since most work was done earlier, before the widespread use of 31P NMR methods. 

Summary of Stereochemical Results for Phosphoryl Transfer Reactions (Type b) by Use of a Thiophosphoryl Group... 

The alkyl exchange reaction (207) differs from the Michaelis-Arbuzov reaction in that the phosphonium intermediate is generated by nucleophilic attack by a phosphoryl or thiophosphoryl group. 

A reaction of greater preparative value is the desulphurization which occurs when 0,0-dialkyl alkylphosphonothioates are acted upon by carbonyl chloride (Stirling, 1957), a reaction which may be envisioned as a consequence of the pronounced nucleophilic character of the thiophosphoryl group as indicated in Scheme 32, in which either X or Z is sulphur desulphurization occurs when Z = sulphur However, the positive results so depicted contrast with the lack of reactivity of phosgene towards both Et(EtO)P(S)OMe and Et(EtO)P(0)SMe reported slightly later " and with the novel nature of the interaction of similar esters with POCI3, when the products are of the structure Ph(RS)P(0)CP . The nature of the ligands to phosphorus has a marked effect on the ability of the reaction... 

Some chemical reactions which destroy the very nature of the phosphoryl bond P=Z (Z = O), also occur when Z = S or Se. The treatment of [(dichlorophosphino)methyl]phos-phonothioic dichloride (13 X = Cl) with SbF5 results in the initial replacement of all the chlorine by fluorine, followed by further fluorine transfer and the formation of the mono(tetrafluorophosphorane) (14) this step is then followed by the destruction of the thiophosphoryl group to give 15 on the other hand, SbF3 does not convert 16 (X = Cl) into 17, although 16 (X = F) is formed The phosphoryl group is not replaced by PF2 when acted upon by SbFj or AsF3". ... 

Teichmann and Hilgetag (131) have summarized and discussed the various chemical aspects of the thiophosphoryl group in terms of the HSAB principle. The P=S group may behave as an electrophile (P end) or as a nucleophile (S end). 

Stereochemistry of the substitution at phosphorus (retention, inversion, or nonstereospecificity) can be investigated by use of chiral [ 0]thiophosphoryl groups (Scheme 2). 

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