T. A. Baronova

Synthesis and steric structure of 3′,3′,5′-trimethyl-7′,7′-bis(trifluoromethyl)spiro[1,3,2-benzodioxaphosphole-2,1′-[2,6,8]trioxa[1λ5]phosphabicyclo[3.2.1]octane] and 3′,5′-dimethyl-7′,7′-bis(trifluoromethyl)spiro[1,3,2-benzodioxaphosphole-2,1′-[2,6,8]trioxa[1λ5]phosphabicyclo[3.2.1]oct[3]ene]

Reactions of hexafluoroacetone with 4-(1,3,2-benzodioxaphosphol-2-yloxy)-4-methylpentan-2-one and 4-(1,3,2-benzodioxaphosphol-2-yloxy)pent-3-en-2-one afforded cage spiro phosphoranes with a phosphorus-carbon bond, 3′,3′,5′-trimethyl-7′,7′-bis(trifluoromethyl)spiro[1,3,2-benzodioxaphosphole-2,1′-[2,6,8]-trioxa[1λ5]phosphabicyclo[3.2.1]octane] and 3′,5′-dimethyl-7′,7′-bis(trifluoromethyl)spiro[1,3,2-benzodioxaphosphole-2,1′-[2,6,8]trioxa[1λ5]phosphabicyclo[3.2.1]oct[3]ene], whose structure was determined by X-ray analysis.

2-chloro-3,3,5-trimethyl-2,3-dihydro-1,2λ5-oxaphosphole 2-oxide as precursor in a new synthesis of dialkyl(diaryl)-(2-methyl-4-oxopent-2-yl)phosphine oxides

A new approach has been developed to the synthesis of dialkyl(diaryl)(2-methyl-4-oxopent-2-yl)-phosphine oxides that are structural analogs of the drug dimephosphon. This approach is based on the reaction of 2-chloro-3,3,5-trimethyl-3H-1,2λ5-oxaphosphole 2-oxide with Grignard compounds, and it ensures high yields of the target products. The structure of bis(2-methoxyphenyl)(2-methyl-4-oxopent-2-yl)phosphine oxide was determined by X-ray analysis. (2-Methyl-4-oxopent-2-yl)dipropylphosphine oxide with magnesium bromide formed a 4: 1 complex whose structure was also determined by X-ray analysis.

A NEW VERSATILE SYNTHESIS OF FUNCTIONALIZED PHOSPHINE OXIDES—EFFICIENT LIGANDS FOR RARE-EARTH METALS EXTRACTION

Abstract A new approach to the synthesis of 2-hydroxyaryl-alkenylphosphine oxides and dialkyl (diaryl)-(2-methyl-4-oxopent-2-yl)phosphine oxides was developed that involves an interaction of Grignard reagents with available benzo[e]-1,2-oxaphosphorinines and 1,2-oxaphospholene-2-oxide. This approach allows obtaining target compounds with a high yield. The synthesized phosphine oxides proved to be highly efficient extractants in the micellar extraction of some lanthanides from the nitric acid media.

A simple synthetic approach to unsymmetrically substituted (γ-oxoalkyl)phosphine oxides

Phosphine oxides and phosphines having a chiral phosphorus atom, including optically active compounds, are successfully used as ligands for metalcomplex catalysts in organic and asymmetric synthesis [1–3]; some derivatives are known as pesticides and biologically active substances [4]. However, more extensive application of these compounds is seriously limited due to complexity of methods for the preparation of phosphine oxides and phosphines with three different substituents, especially with those containing additional functional groups. Taking into account continuously growing demands for such compounds, development of accessible procedures for their synthesis remains to be important (see, e.g., [3–7]). Most known procedures require the use of expensive reagents and are complex and laborious; isolation of intermediate and final products is often difficult. Either racemates are obtained with subsequent optical resolution or stereoselective syntheses are necessary.

Reaction in a three-component system tetrachloro-o-benzoquinone-arylacetylene-phosphorus trichloride

Reaction in a three-component system tetrachloro-o-benzoquinone-arylacetylene-phosphorus trichloride was investigated with the use of NMR and IR spectroscopy and high resolution mass spectrometry. It was established that prevailingly formed 4-aryl-2-oxo-2,5,6,7,8-pentachlorobenzo[e]-1,2-oxaphosphorin-3-enes which on hydrolysis furnished 2-aryl-2-(1-hydroxy-2,3,4,5-tetrachlorophenyl)vinylphosphonic acids.

The New Data for the Reaction of Arylenedioxy Trihalogenophosphoranes with Alkyl- and Arylacetylenes

The new data concerning the reaction between substituted arylenedioxy trihalogenophosphoranes and monoalkyl- or arylacetylenes are summarized. The reaction leads to formation of six-membered heterocycles-2-oxo-4-R-benzo[ e ]-1,2-oxaphosphorin-3-enes. The substituent effects in the phosphorane and acetylene molecules on the ipso -substitution and halogenation regiochemistry are discussed. The ipso -substitution of tert -butyl group on chlorine and the exchange of bromine on chlorine and iodine on hydrogen have been observed, along with formation of benzophosphorines. The interaction of tetrachloro- ortho -benzoquinone with phosphorus trichloride and arylacetylenes is proposed as a new modification of the reaction leading to the formation of benzo[ e ]-1,2-oxaphosphorines. The structures of some benzo[ e ]-1,2-oxaphosphorines are determined by the single crystal X-ray diffraction.

Tandem dihetero-Diels-Alder and Huisgen cycloaddition reactions. Synthesis, crystal structure and hydrolysis of the novel cage phosphoranes based on 2-(1-phenylethenyloxy)benzo-1,3,2-dioxaphosphole

The reaction of 2-(1-phenylvinyloxy)benzo-1,3,2-dioxaphosphole with hexafluoroacetone, ethyltrifluoropyruvate and chloral leads to the formation of cage phosphoranes possessing the 1-phospha-2,6,8-trioxabicyclo[3.2.1]octane framework whose structure was established by the XRD method and NMR spectroscopy. The process involves dihetero-Diels–Alder and Huisgen 1,3-dipolar cycloaddition reactions and is accompanied by the simultaneous formation of the P–C and C–C bonds. Despite the generation of three chiral carbon atoms, the stereoselectivity of the process exceeds 96%. Hydrolysis leads to the formation of functionalized aldols and phosphonates.