Arylphosphinic acids

Issleib, K., Balszuweit, K., Richter, S., and Koetz, J., Arylphosphonic or Arylphosphinic Acid Trimetyhylsilyl Esters, East German Patent 219,776, 1985. 

Preparation and Properties of 7V-(Hydroxy-carbonylmethyl)aminomethyl Alkyl- and Arylphosphinic Acids and Derivatives... 

The reaction of alkyl- and aryldichlorophosphines (or phos-phonous acids) with N-benzylglycine and formaldehyde in acidic solution yields (N-benzyl-N-hydroxycarbonylmethyl-aminomethyl) alkyl- and -arylphosphinic acids of structure 1 (R = alkyl, HOCH2) " " " depending on the electronegativity... 

Debenzylation with hydrogen in the presence of Pd/C as a catalyst in acetic acid or alcohol/water produces N-hydroxycarbonylmethyl-aminomethyl)alkyl- and -arylphosphinic acids (3)... 

Alkyl- or arylphosphinic acids form from reaction of HjO with dialkylphos-phinous halides at 100°C ... 

G. Keglevich, A. Szekrenyi, M. Sipos, K. Ludanyi, 1. Greiner, Synthesis of cyclic aminomethylphosphonates and aminomethyl-arylphosphinic acids by an efficient microwave-mediated phospha-Mannich approach. Heteroatom Chem. 19 (2008) 207-210. 

Heck tried the reductive dimerization of isoprene in formic acid in the presence of triethylamine at room temperature using 1% palladium phosphine catalysts to give dimers in up to 79% yield (95). Better selectivity to the head-to-tail dimer was obtained by using Pd(OAc)2 with 1 1 ratio of arylphosphines. THF as solvent showed a favorable effect. In a scaled-up reaction with 0.5 mole of isoprene using 7r-allylpalladium acetate and o-tolyphosphine, the isolated yield of the dimers was 87%. The dimers contained 71% of the head-to-tail isomers. The mixture was converted into easily separable products by treatment with concentrated hydro-... 

With this last point in mind, the synthesis of mono-, bis- and tra-sulfonated triphenylphosphine will be described, but the same methodology can be applied to the preparation of other sulfonated arylphosphines. In general, these phosphines are made by direct sulfonation using fuming sulfuric acid (oleum) [21], The extent of sulfonation is determined by the SO3 strength, as well as factors such as the temperature and time of the reaction. The monosulfonated phosphine (tppms) is prepared using oleum of 20% SO3 strength, with typically 30% SO3 used... 

Numerous d cobalt(III) complexes are known and have been studied extensively. Most of these complexes are octahedral in shape. Tetrahedral, planar and square antiprismatic complexes of cobalt(lII) are also known, but there are very few. The most common ligands are ammonia, ethylenediamine and water. Halide ions, nitro (NO2) groups, hydroxide (OH ), cyanide (CN ), and isothiocyanate (NCS ) ions also form Co(lII) complexes readily. Numerous complexes have been synthesized with several other ions and neutral molecular hgands, including carbonate, oxalate, trifluoroacetate and neutral ligands, such as pyridine, acetylacetone, ethylenediaminetetraacetic acid (EDTA), dimethylformamide, tetrahydrofuran, and trialkyl or arylphosphines. Also, several polynuclear bridging complexes of amido (NHO, imido (NH ), hydroxo (OH ), and peroxo (02 ) functional groups are known. Some typical Co(lll) complexes are tabulated below ... 

Complexes of tripodal hexa-arylphosphine ligands 242 [484], phospharyl-alkynes (R — C P) [490], and chiral derivatives of phosphoric acid [495], in all of which the P—M bonds are present, are widely known. 

Interest in the Staudinger reaction of phosphines with azides, and the Mit-sunobu reaction involving nucleophilic attack by phosphorus at nitrogen in esters of diazodicarboxylic acids, has continued. Systems of the type (205) have been obtained from the reactions of secondary arylphosphines with azides. Treatment of these with butyllithium results in deprotonation to form the diaminophosphonium diazaylides (206). Phosphazenes have been prepared from azido-quinolines and -triazines, and also from diazoketones " and polycyanocyclopropanes. The Staudinger reaction has been employed in the synthesis of phosphorus-containing dendrimers, and in new approaches to amide and peptide synthesis. The reaction has also been used in a high-... 

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