Methyl phenyl phosphinate

Treatment of 107 with 75 in the presence of 0.15-0.45 mol. equivalent of p-toluenesulfonic acid for 40 - 50 h at room temperature gave60 the (5RS)-5-[(RS)-dimethoxyphosphinyl]-5-(p-tolylsulfonylhydrazino)hexo-furanoses 108 (70% yield). Likewise, compound 107 and methyl phenyl-phosphinate gave an 100% yield of the 5-[(methoxy)phenylphos-phinyl] compound 109, whereas hydrazone 106 afforded four products, namely, two isomers of the xylofuranoses 110 (15%) and two isomers of the 5-C-[(RS)-(0,P-anhydro)phenylphosphinyl] derivatives 111 (51 and 26%). Compound 111 was considered to be produced from 110 during isolation employing sodium hydrogencarbonate, because 110 readily afforded 111 by treatment with sodium methoxide. 

A comparative study of the effects of Li+ and K+ on the ethanolysis of a series of X-phenyl methyl phenyl phosphinates (97) has revealed that Eto- is < MOEt, contrary to the generally observed reactivity order in nucleophilic substitution processes.93... 

Photolysis of (244) in the presence of alcohols likewise results in the formation of esters of methyl(phenyl)phosphinic acid. However, O-isotopic labelling studies provide evidence of, at least, the partial involvement of a pentacovalent phosphorus intermediate in this reaction, and so the previous assumption of the intermediacy of (245) may not be the whole story. The phosphole oxide dimers (246) have been shown to undergo regioselective reduction and complexation on treatment with the dimethylsulfide-borane adduct, to form the bicyclic system (247). Treatment of the propadienylphosphine oxide... 

As has been the pattern in recent years, there has been considerable interest in the synthesis and characterisation of phosphide reagents derived from metals other than lithium, sodium, and potassium, and also in studies of the structure of metallophosphides in the solid state. A new route to P-chiral phosphine-boranes of high enantiopurity is afforded by treatment of the borane complexes of methyl(phenyl)phosphine with a copper(I) reagent, giving the copper-phosphido intermediate (83), which, on subsequent treatment with an iodoarene in the presence of a palladium(O) catalyst, gives the related chiral t-phosphine-borane (84), with retention of configuration at phosphorus. Organophosphido systems... 

Recovery of phosphinylated acetylcholinesterase was also greatly enhanced in our studies of methyl parathion-resistant tobacco budworm larvae (Figure 5). Phosphinylated acetylcholinesterase recovery can be measured without the complication of "aging" which occurs with phosphorylated enzyme (Figure 6). Activity was totally inhibited with 4-nitrophenyl methyl(phenyl)phosphinate. Excess inhibitor was removed by solid phase extraction and recovering activity at 30°C was monitored in aliquots. We have confirmed this insensitivity with individual heads of adults from these strains and we are investigating inheritance of this trait. 

The data show that both techniques yield consistent results. However, different ionization ratios have been evaluated at the same acidity for methyl phenyl phosphinate by following the CH3 or OCH3 proton resonance chemical shifts with respect to the trimethyl-ammonium ion (Curci et al., 1973). This evokes a word of caution in the use of internal standards, although in many cases (see Fig. 1) very good results have been obtained. 

H4Au4FtP,ReC 4H,o2, Rhenium(l+), tetrahydridobis[tris(4-methyl-phenyl)phosphine]tetrakis (triphenyl-phosphine)gold]-, hexafluorophos-phate(l-), 29 292... 

An unusual arrangement for three-coordinate iodine is found in the structure of the cation [Rh3(/t-dpmp)2(/i-I)2(/i-CO)(CO)2] (where dpmp = bis[(diphenylphosphino)methyl]phenyl-phosphine). The iodine atom and three rhodium atoms lie in a plane and form a distorted rectangle with Rh—I—Rh angles of 58.3° and 60.3°. Although one Rh—I distance of 3.149 A is long compared with the others of 2.801 and 2.865 A, it does appear to represent a significant interaction. 

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