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Hydroxymethylphosphine

The introduction of different cations in the IL, which served as a solvent, resulted in considerable changes in enantioselectivity of the reaction. The best results both in terms of selectivity and activity were obtained for [EMIM] [BF4]. However, in the case of heteroorganic substrates, namely hydroxymethylphosphinates, the best results were obtained using [BMIM] [PFe], while [BMIM] [BF4] proved to be completely useless [65c]. [Pg.107]

Berning, D.E. et al. (1999) Chemical and biomedical motifs of the reactions of hydroxymethylphosphines with amines, amino acids and model peptide./. Am. Chem. Soc. 121(8), 1658-1864. [Pg.1047]

Depending on the relative amount of reagents, three types of products may be obtained in the reaction of hydroxymethylphosphines with amines acyclic aminomethylphosphines, 1,3,5-diazaphosphorinanes, and 1,5,3,7-diazadiphosphacyclooctanes. Indeed, the interaction of phosphorus-containing diols with 1 mol of amine gives eight-membered heterocycles. The initial assumption about the formation of 1,3-azaphosphetidines... [Pg.73]

Siegfried, B., Calcium Salt of Hydroxymethylphosphinic Acid, Swiss Patent 311,982, 1956. [Pg.90]

The hydroxymethylphosphonium ion first formed changes into mono-hydroxymethylphosphine by releasing a proton. This phosphine reacts further in the same way as phosphine itself until finally the quarternary phosphonium ion is formed. For a bimolecular reaction mechanism, the first stage must be assumed to be the formation of a carbonium ion from the aldehyde molecule and a proton. This ion then reacts with phosphine. [Pg.40]

Method A Reaction of Pyrylium Salts with Tris-hydroxymethylphosphine... [Pg.20]

The direct reaction of4.4 -bis-2.6.2/6 -tetraphenyl-pyrylium tetrafluoroborate with tris-hydroxymethylphosphine did not lead to the desired product. [Pg.26]

Kielbasinski P, Albiycht M, Luczak J, Mikolajczyk M (2002) Enzymatic reactions in ionic liquids lipase-catalysed kinetic resolution of racemic, P-chiral hydroxymethanephosphinates and hydroxymethylphosphine oxides. Tetrahedron Asymm 13 735-738... [Pg.186]

JX Guo, DG Gray. Inhibition of light-induced yellowing of the high-yield pulp by sodium hydroxymethylphosphinate. J Pulp Paper Sci 22(2) 64-70, 1996. [Pg.492]

Hydroxymethylphosphinic acid, HO.CH2-PO(OH)2.—This acid is said to result from the interaction of trioxymethylene and phosphorus trichloride. It crystallises in wRite, rectangular plates, very hygroscopic and deliquescent, and it is a dibasic acid. The following salts are known barium salt, pearly plates silver salt, w-hite amorphous pow der pyyidinium salt, HO.CH2.PO(OH)2.C5H5N, ghstening needles, M.pt. 105° C. calcium, lead and zinc salts, w hite, amorphous powders copper salt, pale blue ferric salt, pale yellow calcium and barium hydrogen salts cannot be obtained in solid form,... [Pg.35]

Scheme 89 Biocatalytic kinetic resolution of racemic hydroxymethylphosphinates 271... Scheme 89 Biocatalytic kinetic resolution of racemic hydroxymethylphosphinates 271...
Biocatalytic kinetic resolution of racemic hydroxymethylphosphinates 271 via their lipase-promoted acetylation in supercritical carbon dioxide as the reaction medium was investigated. The reaction was fastest when pressure was closer to the critical pressure at 11 MPa the reaction rate reached its maximum when the pressure was increased to 15 MPa. The optimal conditions were obtained at 13 MPa (yields 50%, 30% ee). The stereoselectivity of the reaction depended on solvent, substituents at phosphorus, and solubility of substrates in SCCO2. The best results were obtained with the Candida antarctica lipase (Novozym 435) (Scheme 89) [183, 184]. [Pg.216]

Shioji K, Kurauchi Y, Okuma K (2003) Novel synthesis of P-chiral hydroxymethylphosphine-boranes through lipase-catalyzed optical resolution. Bull Chem Soc Jpn 76 833-834... [Pg.234]

Hydroxymethylphosphine boranes 11 were found to be useful intermediates for further transformations (Scheme 5.7). [Pg.240]

A report of Shioji and co-workers studied the kinetic resolution of hydroxymethylphosphine boranes 147 by lipase-catalysed acylation reactions (Scheme 6.57). [Pg.350]

Hydroxymethylphosphine oxides (149) proved to be excellent substrates for kinetic resolution, as reported by Shioji and co-workers (Scheme 6.58). ° ... [Pg.350]

Scheme 6.57 Lipase-catalysed enantioselective acylation of hydroxymethylphosphine boranes. Scheme 6.57 Lipase-catalysed enantioselective acylation of hydroxymethylphosphine boranes.
Vinylic phosphate (192) has been reported to react as Michael acceptor with alcohols in basic catalytic conditions to afford, in the case of ethylene glycol, the expected adduct (193). Under similar conditions, the hydroxymethylphosphine oxide (194), used as alcoholic reagent, loses formaldehyde and the salt (195) thus generated adds to vinylphosphine oxide (192) in a Michael fashion to produce 1,2-diphosphosphine oxide (196). 4... [Pg.479]

Hydroxylmethylphosphine synthesis has been a feature of the Henderson group. On reaction with formaldehyde, the ferrocenyl phosphines FCPH2 and l,l -Fc(PH2)2 produce the hydroxymethylphosphines FcP(CH20H)2 and... [Pg.198]


See other pages where Hydroxymethylphosphine is mentioned: [Pg.187]    [Pg.193]    [Pg.328]    [Pg.147]    [Pg.85]    [Pg.33]    [Pg.21]    [Pg.24]    [Pg.4130]    [Pg.43]    [Pg.217]    [Pg.721]    [Pg.381]    [Pg.16]    [Pg.17]    [Pg.25]    [Pg.4129]    [Pg.11]    [Pg.35]    [Pg.15]    [Pg.192]    [Pg.29]    [Pg.117]    [Pg.379]    [Pg.240]    [Pg.174]    [Pg.15]    [Pg.14]    [Pg.406]   


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A Reaction of Pyrylium Salts with Tris-hydroxymethylphosphine

Hydroxymethylphosphinates

Hydroxymethylphosphinates

Hydroxymethylphosphine boranes

Hydroxymethylphosphine oxides

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