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1.
The reaction of pyruvonitrile with 2-tetrafluoropropoxy-5,6-benzo-1,3,2-dioxaphosphorinan-4-one results mainly in the enlargement of the starting heteroring to form 4-cyano-4-methyl-2-tetrafluoropropoxy-6,7-benzo-1,3,25-dioxaphosphepin-5-one 2-oxide as a mixture of two diastereomers (14:1) along with minor amounts of 3-cyano-3-methyl-2-tetrafluoropropoxy-6,7-benzo-1,4,25-dioxaphosphepin-5-one 2-oxide.  相似文献   
2.
Benzo-1,3,2,dioxaphosphorin-4-ones react with hexafluoroacetone imine to form 2-R-2,5-dioxo-3,3-bis(trifluoromethyl)-6,7-benzo,1,4,2-oxozaphosphepanes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No, 12, pp. 3008–3010, December, 1996.  相似文献   
3.
The reaction of hexafluoroacetone with 2-alkoxy-6(7)-chloro-1,3,2-benzodioxaphosphorin-4-ones yielded 7-and 8-chloro-substituted 2-alkoxy-2,5-dioxo-4,4-bis(trifluoromethyl)-1,3,2λ5-benzodioxaphosphepines. Their steric structure was studied by single-crystal X-ray diffraction. The effect of fluorinated substituents on the crystal packing of the benzophosphepines was demonstrated. Hydrolysis of these compounds gave the corresponding 4-and 5-chloro-substituted 2-(2-hydroxyphenyl)-2-oxo-1,1-bis(trifluoromethyl)-ethanols; the structure of 2-(2-hydroxy-5-chlorophenyl)-2-oxo-1,1-bis(trifluoromethyl)ethanol was also proved by single-crystal X-ray diffraction.  相似文献   
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Abstract

Nucleophilicity of (I) in reactions with such carbonyl compounds as chloral, benzyl, ester and nitrile of benzoylformic acid is found to be notably reduced by the electronoaccepting perfluoropropyl groups. Unlike of dialkyl isocyanatophosphites (I) afford the cycloaddition products with ≡P-N- fragment (II) which being unable for the imide-amide rearrangement undergo dimerization into crystalline cyclodiphosphazanes (III) with pentacovalent phosphorus atoms.  相似文献   
7.
Abstract

Hexafluoroacetone imine easily interacts with compounds (I, R = OMe, OCH2CF2CHF2, NEt2, Ph) in two directions unlike hexafluoroacttone and gives 1,4,2-oxazaphosphepines (II) (pathway I) or 1,3,2-oxszaphosphepines (III) (pathway 2). The compound (II) (R = NEt2) lightly hydrolyzes to yield the salt (IV). The structure of heterocycles II-IV) has been confirmed by X-ray analysis (see fig. I, II, R = OMe; fig. 2, IV). The detail structural peculiarities of the compounds am discussed.  相似文献   
8.
Phosphorylation of 2-hydroxyphenyl 2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl ketone with dichloro(phenyl)phosphine gave 5-oxo-2-phenyl-4,4-bis(trifluoromethyl)-4,5-di-hydro-1,3,2-benzodioxaphosphepine. Heating of the latter initiated an intramolecular interaction of the P atom with the carbonyl group. Hydrolysis of the intermediate product yielded 3-hydroxy-2-oxo-2-phenyl-3-[2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl]-2,3-di-hydro-1,2λ5-benzo[d]oxaphosphole. The reaction was highly stereoselective (PRCS/PSCR). The reaction of the starting phosphepine with chloral proceeded highly stereoselectively (PRCSCS/PSCRCR) to give a 5-carbaphosphatrane derivative containing a four-membered ring, namely, 1-phenyl-3-trichloromethyl-10,10-bis(trifluoromethyl)-6,7-benzo-2,4,8,9-tetraoxa-1λ5-phosphatricyclo[3.3.2.01,5]decene. The trigonal bipyramid of the 5-carbaphosphatrane derivative is made up of the equatorial O atoms and the apical C atoms.  相似文献   
9.
The survey summarizes modern methods of synthesis and reactivity of tetracoordinated phosphorus cage compounds containing one or more endocyclic P–C bonds (phosphine oxides, phosphinates and phosphonates, phosphatripticenes and others). Intramolecular cyclization reactions including electrophilic aromatic substitution with unsaturated organophosphorus compounds, reactions of P–H-derivatives with carbonyl compounds as well as cycloaddition reactions involving I–IV-coordinated phosphorus derivatives are considered.  相似文献   
10.
Reaction of hexafluoroacetone and chloral with 2-R-naphtho-1,3,2-dioxaphosphorin-4-ones yields 2-R-2,5-dioxo-4,4-bis(trifluoromethyl)naphthol-1,3,2-and 2-R-2,5-dioxo-3-trichloromethylnaphtho-1,4,2λ5-dioxaphosphepins. Hydrolysis of the fluorophosphepins gives naphthyl-substituted fluorinated hydroxy ketones. The steric structure of the dioxaphosphepins and some fluorinated ketones was confirmed by single crystal X-ray diffraction. A competition between the π-π and halogen-halogen interactions and hydrogen bonds of classic type in the formation of crystal packing and supramolecular structure was revealed.  相似文献   
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