Synthesis of esters of bis(alkoxymethyl) phosphinic acids

Conclusions A method was developed for the production of esters of bis(alkoxymethyl)phosphonic acids, and some of these esters were synthesized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 710–716, 1969.     

Synthesis of some derivatives of bis (N,N-dialkylaminomethyl)phosphinic acids

Conclusions A number of derivatives of bis(N,N-dialkylaminomethyl)phosphinic acids have been obtained by the reaction of dialkylamines with esters and amides of bis(chloromethyl) phosphinic acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1346–1348, June, 1967.     

Synthesis and properties of bis [N-Alkyl(aryl)-aminomethyl]phosphinic acids

Conclusions Reaction of primary aliphatic and aromatic amines with bischloromethylphosphinic acid yielded a series of bis(N-alkyl(aryl)aminomethyl)phosphinic acids and the methacroylamides of several of them were obtained.Translated from Izvestiya Akademii Nauk SSSR, Seriya Kkimicheskaya, No. 8, pp. 1860–1862, August, 1968.     

The first separation and stereochemical determination of bis(α-hydroxyalkyl) phosphinic acids diastereoisomers

A separation of bis(α-hydroxyalkyl) phosphinic acid diastereoisomers is described. A novel method for the determination stereochemistry of bis(α-hydroxyalkyl) phosphinic acid diastereoisomers has been developed. The stereochemistry of one diastereoisomer was confirmed after converting to the corresponding methyl ester using trimethyl orthoformate.     

A novel method for the separation of bis(alpha-hydroxyalkyl)phosphinic acid diastereoisomers via formation of novel cyclic phosphinic acids

The reaction of aromatic and aliphatic aldehydes with hypophosphorus acid under microwave irradiation was examined. The reaction gave a mixture of a racemic pair of bis(alpha-hydroxyalkyl)phosphinic acids and acetal derivatives from the corresponding bis(alpha-hydroxyalkyl)phosphinic acids of meso-stereochemistry in good yield. The difference in solubility in organic solvents due to polarity allowed us to readily separate these compounds. This method constitutes an easy, rapid, and good-yielding preparation and separation of bis(alpha-hydroxyalkyl) phosphinic acid diastereoisomers from simple starting materials using microwave irradiation.     

Group 1 and 13 complexes of aryl-substituted bis(phosphinimino)methyls

The organolithium reagent [{HC(Ph₂PNC₆H₂Me₃-2,4,6)₂}Li(OEt₂)] was easily obtained by deprotonation of H₂C(Ph₂PNC₆H₂Me₃-2,4,6)₂ with nBuLi in diethyl ether solution. The crystal structure of [{HC(Ph₂PNC₆H₂Me₃-2,4,6)₂}Li(OEt₂)] has been determined and shown to consist a monomeric chelate structure that contains a distorted, trigonal planar lithium centre. The ligand precursor has also been deprotonated with both Me₃Al and Me₂AlCl to yield the tetrahedral organoaluminium complexes, [{HC(Ph₂PNC₆H₂Me₃-2,4,6)₂}AlMe₂] and [{HC(Ph₂PNC₆H₂Me₃-2,4,6)₂}Al(Cl)Me]. Reaction of [{HC(Ph₂PNC₆H₂Me₃-2,4,6)₂}Li(OEt₂)] with either AlX₃ (X=Cl, Br, I) or GaCl₃ yielded a series of dihalo derivatives [{HC(Ph₂PNC₆H₂Me₃-2,4,6)₂}MX₂] all of which have been shown to exist as similar monomeric species containing four-coordinate group 13 centres.     

Kinetics of the alkaline hydrolysis of bis(chloromethyl)phosphinic esters

Conclusions The kinetics of the hydrolysis of bis (chloromethyl)phosphinic esters was investigated in KOH medium at 10 and 25°. The rate constants are correlated with the steric constants of the leaving groups.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 923–924, April, 1967.     

Synthesis of alkyl- and aryl(o-oxyphenoxymethyl) phosphinic acids

Conclusions Cleavage of 2-oxo-2-chloromethyl-1,3,2-benzodioxaphosphole by Grignard reagents produced pyrocatechol esters of alkyl- and aryl(chloromethyl)phosphinic acids, cyclization of which and subsequent hydrolysis lead to alkyl- and aryl(o-oxyphenoxymethyl)phosphinic acids.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 943–946, April, 1989.     

EPR and electronic spectral properties of aryl-substituted bis(dithiophosphato)copper(II) complexes

The spectral properties of bis(diaryl-dithiophosphato)copper(II) complexes, [Cu(S(2)P(OR)(2))(2)], with R = o-cresyl (complex I) and 2,6-dimethylphenyl (complex II) are studied by EPR- and vis spectroscopy. In solid (powder) state both complexes exhibit dark brown colour and are paramagnetic. Room temperature EPR spectra of the complexes dissolved in non-coordinating (C(6)H(5)CH(3), C(5)H(12), C(6)H(14)), acceptor (CHCl(3), CCl(4)) or donor (DMFA, DMSO) solvents have typical features of the chromophore CuS(4). In non-coordinating and acceptor solvents their isotropic EPR parameters are: g(iso)=2.047+/-0.003, (Cu)A(iso) = 7.2+/-0.1 mT and (P)A = 0.95+/-0.1 mT. An absorption band characterizes the vis spectra in these solvents with a maximum at 427 nm, due to a ligand-to-metal charge-transfer transition. One hour after dissolution the absorbance at 427 nm follows Beer's law with molar absorptivity (epsilon) about 11000, which does not change significantly after 24 h staying at room temperature or after 30 min heating at 50 degrees C. Both DMFA and DMSO exhibit specific solute-solvent interaction with the acceptor centre of copper complex yielding an axial adduct, with increased g-factor and decreased (hf)A compared to the initial complex. An additional EPR signal with unresolved hyperfine structure is also detected in DMSO. EPR and vis intensities of both bis(diaryl-dtp)Cu(II) complexes decrease after dissolution in both solvents. Moreover, they are EPR silent in pyridine and do not show any absorption in the vis spectra.     

Organic phosphorus compounds : LXXI. Preparation,properties, and structure of bis(aminomethyl)phosphinic acid, (H2NCH2)2P(O)OH

Bis(aminomethyl)phosphinic acid, (H₂NCH₂)₂P(O)OH · HCl, was prepared by debenzylation of (C₆H₅CH₂NHCH₂)₂P(O)OH · HCl with hydrogen using 5% Pd on C as catalyst, and from bis(t-butylaminomethyl)phosphinic acid, (t-C₄H₉NHCH₂)₂P(O)OH, by isobutylene elimination in concentrated aqueous hydrobromic acid at 175°C in sealed tube. Interaction of bis(chloromethyl)phosphinic acid with ammonia in an autoclave produced methylaminomethylphosphinic acid, CH₃NHCH₂P(O)(OH)₂. A mechanism for the formation of this product is proposed. Several derivatives of (H₂NCH₂)P(O)OH such as (RNHCH₂)₂P(O)OH, R = C₆H₅CO, CICH₂CO, [H₂NHNC(=NH)NHCH₂]₂P(O)OH and [(CH₃)₃SiNHCH₂]₂P(O)OSi(CH₃)₃ were prepared.     

Kinetics of the hydrolysis of ethers of bis(chloromethyl)phosphinic acid

Conclusions A study was made of the hydrolysis kinetics of some esters of bis(chloromethyl)phosphinic acid in water at 75–95°. The reaction rate depends on the nature of the alcohol radical, and for the alkyl radicals is determined by the steric factor.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1654–1655, September, 1966.     

Solvent extraction of rare-earth metals with bis(2-ethylhexyl)phosphinic acid

 The extraction behavior of tervalent rare-earth metals (Ln) using a heptane solution containing bis(2-ethylhexyl)phosphinic acid (PIA-8, HR) from 0.1 mol/dm³ sodium perchlorate media was studied. The pH_0.5 values and separation factors obtained were compared among the metals. The stoichiometry of the extracted species and the extraction constants for the present aqueous/heptane system were determined by slope analysis. It is demonstrated that the rare-earth metals were extracted as monomers LnR₃⋅mHR (m=3, 4, 5 or 6), and the extracted species could be stripped into a relatively low concentrated hydrochloric acid. PIA-8 was found to be the most selective extractant for the mutual separation of rare-earth metals among the other phosphinic acids reported. Received: 27 February 1996/Revised: 13 May 1996/Accepted: 21 May 1996     

Ab initio calculation of boat benzenes in bis(2,4,6-tri-t-butylphenyl) phosphinic chloride

ab initio Calculation of the benzene skeletons of the titled compound indicated that the molecule suffers 61.4 kcal/mol higher energy than that of flat benzene rings and that the boat benzene form is even more stable than the envelope or chair form benzene.     

Extraction separation of tervalent lanthanide metals with bis(2,4,4-trimethylpentyl)phosphinic acid

The extraction behavior of certain tervalent lanthanides (Ln) such as La, Pr, Eu, Ho and Yb, using a chloroform solution containing bis(2,4,4-trimethylpentyl)phosphinic acid (HBTMPP), either alone or combined with one of three adductants, trioctylphosphine oxide (TOPO), octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) or methylenbis(diphenylphosphine) oxide (MBDPO), was studied. The stoichiometry, extraction constants and separation factors of these systems were determined. Lanthanide ions were found to be extracted in the presence of TOPO (B), Ln(HL₂)₃, or as the adduct complexes, Ln(HL₂)₂B. Neither CMPO nor MBDPO was found to form adducts.     

A very crowded molecule: formation of bis(2,4,6-tri-t-butylphenyl)phosphinic chloride

Reaction of 2,4,6-ri-t-butylphenyllithium with phosphoryl trichloride gave a very crowded compound, bis(2,4,6-tri-t-butylphenyl)phosphinic chloride ($\text{1}$), and 2,4,6-tri-t-butylchlorobenzene ($\text{3}$), while the reaction with thiophosphoryl trichloride afforded $\text{3}$.