Phosphinothioates

It is now well-established that unsymmetrical substituted menthylphosphinates, RR P(0)0Men, as well as the corresponding phosphine-boranes RR P(BH3)OMen and phosphinothioates RR P(S)OMen, can be separated readily into the di-astereomeric forms, and subsequently reacted with Grignard reagents to afford P-chirogenic tertiary phosphines with a high degree of stereospecificity [57]. The... 

The [l,2]-a rearrangement of phosphinothioates into (alkylsulfanyl-methyl)phosphine oxides using a chiral phosphinoyl group has also been reported (see Sect. 5.1.1.). 

The rearrangement has also been extended to P-chiral S-phenyl phos-phinothiolate 79 and 0-phenyl phosphinothioate 80 (Scheme 21). With these asymmetric compounds, the C-P bond formation was found to occur stereose-lectively and with retention of configuration at phosphorus [51]. 

A variety of compounds have been examined which are in the phosphinic acid class. They include a phenyl cyclopentyl ester,184 a phosphinothioic anhydride,185 a dipheny1phosphinamide, 86 a red bis(di-t-buty1thiophosphinamide) and its selenide analogue,187 the anisylphosphor inane (67),1 88 the thioamide (68),1 89 and the phospholenium amide (69, Y = i-Pr2N).190... 

Phosphorus acids containing P—S bonds in which the sulfur atom acts as the metal ligating atom also received much attention.243,252,255-261 The commercially available reagents bis(2,4,4-trimethylpentyl)phosphinothioic acid (Cyanex 302) and bis(2,4,4-trimethylpentyl)dithiophosphinic... 

Several methods were reported for the selective synthesis of a-glycosides in the absence of a controlling group at C-2. The 2-deoxy sugar is first converted into a glycosyl donor by formation of phosphites,53 phophonodithioates,54 or phosphinothioates,55 which react with different acceptors and promoters. 

The reaction of carbodiimides with phosphonothioic and phosphinothioic acid as well as phosphonoselenoic and phosphinoselenoic acids " proceed in a similar manner. 

PHOSPHINOTHIOIC ACID, DIPHENYL-, S-(4-CHLORO-2-BUTYNYL) ESTER see CEV840 l,l, T -PHOSPHINOTHIOYUDYNETRISAZIRIDINE... 

A very detailed study (Scheme 18) of the bromination and iodination of the S-methyl phosphinothioate esters (257) has been... 

In addition to the sulfoximines, Johnson has studied phosphinothioic amides as alkene precursors. This reagent has not achieved the popularity of the sulfoximines. It can be utilized for ketone methylen-ation with resolution, as well as for Ae synthesis of more highly substituted alkenes. Rigby has found that in the synthesis of guaianolides this reagent was effective where Peterson and Wittig reactions gave only p-elimination. ... 

A study has been made of the kinetics of epoxidation of allylphosphinates and of the addition of C-benzoyl-iV-phenylnitrone to vinyl- and allyl-phosphonates. Boron trifluoride stabilizes phosphorus(v) thiocyanates, preventing their isomerization to isothiocyanates. Cleavage of the phosphinothioic methanesulphonic anhydride (97) with aluminium halides yields the phosphinic halide with retained chirality. ... 

Both (R)-(-t-)- and (S)-(-)-tertiarybutylphenylphosphine sulphides (6) have been synthesised in high optical purity from (S)-(-)- and (R)-(+)-tertiarybutylphosphinothioic acids, respectively, by formation of the mixed anhydride (5) followed by borohydride reduction (Scheme 2). Reactions of the product (6) have been used to provide routes to optically active phosphinothioic iodides, phosphinodithioates and thioselenophosphinic acids of known configurations. A new method for the asymmetric synthesis of tertiary phosphine oxides has been reported.5 An Arbusov reaction of the optically active 1,3,2-... 

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