Flame-retardant properties of epoxide and unsaturated polyester resins modified with tertiary phosphine oxides containing chlorinated phenoxy groups

The flame-retardant properties of the epoxide resin “Epoxa AP-2” and the unsaturated polyester resin “Vinalkid 550P” modified with dimethyl(2,4,6-trichlorophenoxymethyl)phosphine oxide (DMPO), methyl-bis(pentachlorophenoxymethyl)phosphine oxide (MBPO) and tris(2,4,6-trichlorophenoxymethyl)phosphine oxide are examined. It is established that all three products are effective fire-retardants for epoxide as well as for unsaturated polyester resins. The effect is notable at about 10–15% presence. The oxygen indexes, determined by the ASTM-D-2863 method, show an increase of several units in comparison with the unmodified resins. The fire-retardant action of DMPO, MBPO and TTPO is significantly enhanced by the addition of Sb₂O₃.     

Bicyclo[2.2.1]heptane derivatives containing two vicinal CFC1 groups. The tendency tocis-dehalogenation

Dehalogenation ofexo-cis-2,3-dichloro-2,3-difIuoro-1,2,3,4,4a,-5,8,8a-octahydro-l,4,5,8-dimethanonaphtalene yields 2,3-difluoro-l,4,4a,5,8,8a-hexahydro-1,4,5,8-dimethanonaphthalene as the sole product, whereas the isomerictrans-dichloride affords a mixture of the above product with 2-chloro-3-fluoro-l,4,4a,5,8,8a-hexahydro-l,4,5,8-dimethanonaphthalene (2 1 respectively).Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 411–413, February, 1993.     

Organic Phosphorus Compounds 52. Preparation and properties of β-hydroxyalkyl-phosphonium salts and tertiary phosphine oxides

The new, tris- (2- hydroxyalkyl) - (hydroxymethyl) - phosphonium salts: [(RCHOHCH₂)₃ PCH₂OH]Cl (I, R = ClCH₂; III, R = CH₃) are formed in high yield by reaction of tetrakis-(hydroxymethyl)-phosphonium chloride (Tetrakis) with epoxides under basic conditions. Under the same conditions, styrene oxide yields only the disubstituted product, [(PhCHOHCH₂)₂ (CH₂OH)₂P]Cl. Optimal pH values for the reactions are 8 to 9; at lower pH the conversion is too slow; at a higher pH, oxidative decomposition of the salts occurs. Conversion of the salts to tertiary phosphine oxides (RCHOHCH₂)₃P ? O (R ? ClCH₂; CH₃) with loss of the hydroxymethyl group is best carried out with chlorine at pH 5 to 7. The yields are usually 60 to 90%.     

Monocarbaborane anion chemistry. [COOH], [CH2OH] and [CHO] units as functional groups on ten-vertex monocarbaborane anionic compounds

B(10)H(14) reacts with para-C(6)H(4)(CHO)(COOH) in aqueous KOH solution to give the [nido-6-CB(9)H(11)-6-(C(6)H(4)-para-COOH)](-) anion 1, which undergoes cage closure with iodine in alkaline solution to give the [closo-2-CB(9)H(9)-2-(C(6)H(4)-para-COOH)](-) anion 2. Upon heating, anion 2 rearranges to form the [closo-1-CB(9)H(9)-1-(C(6)H(4)-para-COOH)](-) anion 3. Similarly, B(10)H(14) with glyoxylic acid OHCCOOH in aqueous KOH gives the [arachno-6-CB(9)H(13)-6-(COOH)](-) anion 4, which undergoes cage closure with iodine in alkaline solution to give the [closo-2-CB(9)H(9)-2-(COOH)](-) anion 5. Upon heating, anion 5 rearranges to give the [closo-1-CB(9)H(9)-1-(COOH)](-) anion 6. Reduction of the [COOH] anions 3 and 6 with diisobutylaluminium hydride gives the [CH(2)OH] hydroxy anions [closo-1-CB(9)H(9)-1-(C(6)H(4)-para-CH(2)OH)](-) and [closo-1-CB(9)H(9)-1-(CH(2)OH)](-) 8 respectively. The [closo-1-CB(9)H(9)-1-(C(6)H(4)-para-CH(2)OH)](-) anion 7 can also be made via isomerisation of the [closo-2-CB(9)H(9)-2-(C(6)H(4)-para-CH(2)OH)](-) anion 9, in turn obtained from the [nido-6-CB(9)H(11)-6-(C(6)H(4)-para-CH(2)OH)](-) anion 10, which is obtained from the reaction of B(10)H(14) with terephthaldicarboxaldehyde, C(6)H(4)-para-(CHO)(2), in aqueous KOH solution. Oxidation of the hydroxy anions 7 and 8 with pyridinium dichromate gives the aldehydic [closo-1-CB(9)H(9)-1-(C(6)H(4)-para-CHO)](-) anion 11 and the aldehydic [closo-1-CB(9)H(9)-1-(CHO)](-) anion 12 respectively, characterised as their 2,4-dinitrophenylhydrazone derivatives, the [closo-1-CB(9)H(9)-1-C(6)H(4)-para-CH=N-NHC(6)H(3)(NO(2))(2)](-) anion 13 and the [closo-1-CB(9)H(9)-1-CH=N-NHC(6)H(3)(NO(2))(2)](-) anion respectively.     

Synthesis and studies on spectroscopic as well as electron donating properties of the two alkoxy benzo[b]thiophenes

Synthesis, characterization, steady state and time resolved, using time correlated single photon counting as well as laser flash photolysis techniques, spectroscopic investigations were made for two alkoxy benzo[b]thiophene molecules: 5-methoxy benzo[b]thiophene (5MBT) and 5-methoxymethyl benzo[b]thiophene (5MMBT). In both non-polar n-heptane (NH) and polar acetonitrile (ACN) solvents and at ambient temperature the electronic absorption spectra of these thiophenes exhibit different band systems whose assignments were made from the measurements of the steady state excitation polarization spectra. Steady state fluorescence spectra of these molecules in the different polarity solvents show the presence of non-specific interactions. From the redox properties of the benzothiophenes, measured by cyclic voltammetry, their electron donating properties were observed in the presence of the well-known electron acceptor 9cyanoanthracene (9CNA). Further, detailed studies by laser flash photolysis techniques show that ion-recombination mechanism predominates after the initial excitation of the acceptor moiety using the third harmonic of Nd:YAG laser. This recombination together with the external heavy atom effect (the donor containing 'sulphur' atom) appears to be responsible for the formation of the triplet of the monomeric acceptor 9CNA. From the steady state experiments it is shown that both in non-polar NH and highly polar ACN the quenching in the fluorescence emission of 9CNA in the presence of the benzothiophene donors is brought about primarily by the external heavy atom effect and in ACN, although the presence of the photoinduced ET reaction is confirmed, this process seems, from the observed bimolecular dynamic quenching rate, kq to be significantly masked by the external heavy atom effect.     

Organic dyes containing indolo[2,3-b]quinoxaline as a donor: synthesis,optical and photovoltaic properties

New organic dyes containing indolo[2,3-b]quinoxaline donor have been synthesized for application in dye sensitized solar cells as sensitizers. The dyes exhibited interesting optical properties tuneable by the nature of the conjugation bridge. Origin of the optical transitions in the dyes was corroborated by the TDDFT computations. The LUMO and HOMO of the dyes were found to be favourable for electron injection into the conduction band of TiO₂ and the regeneration of the dye by the redox shuttle in the electrolyte, respectively. Since the dyes exhibited solvent dependent absorption properties, DSSC were fabricated from two different dye bath solutions, DCM and acetonitrile/tert-butanol/dimethylsulphoxide mixture. The dyes adsorbed from the later bath solution led to better device performance owing to the comparatively less charge transfer resistance arising from the well-spaced dye packing. Among all dyes, a dye containing thiophene in the π-spacer exhibited the highest device efficiency.     

Spectral luminescence properties of 1- and 2-alkyl(cycloalkyl) derivatives of benzo[f]quinoline

The absorption and fluorescence spectra of alcohol solutions of 3-aryl-substituted benzo[f]-quinolines were investigated, and the fluorescence quantum yields were measured. It was established that the indicated compounds have intense absorption in the UV region and fluorescence at 350–450 nm. The fluorescence quantum yields range from 5 to 70%, depending on the substituents. The introduction of aromatic substituents in the 1 and 3 positions of benzo-[f]quinoline ring raises the fluorescence quantum yields. A methyl group in the 2 position of the molecule leads to a decrease in the fluorescence quantum yield. Benzo[f]quinoline derivatives that contain a cyclopentene ring in the 1 and 2 positions fluoresce intensely (=40–60%), while cyclohexene and cycloheptene condensed in the same positions cause a decrease in the fluorescence yield to 7–13%; this is associated with the three-dimensional structure of these molecules.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1237–1240, September, 1977.     

Heterocyclization of compounds containing diazo and cyano groups. 3. Two pathways in the cyclization of 2-diazo-2-cyanoacetic acid derivatives under the influence of bases

1,2,3-Triazol-5-olates are formed in the reaction of diazomalonodiamide and 2-diazo-2-cyanoacetic acid amide and N-methylamide with sodium ethoxide, triethylamine, and ammonia. The products of the reaction of 2-diazo-2-cyanoacetamide with primary amines are mixtures of 4-cyano-1,2,3-triazol-5-olates and 5-amino-1-alkyl-1,2,3-triazole-4-carboxamides.See [1] for communication 2.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 926–931, July, 1986.     

HC[triple bond]P and H3C-C[triple bond]P as proton acceptors in protonated complexes containing two phosphorus bases: structures, binding energies, and spin-spin coupling constants

Ab initio calculations at the MP2/aug'-cc-pVTZ level have been carried out to investigate the structures and binding energies of cationic complexes involving protonated sp, sp2, and sp3 phosphorus bases as proton donor ions and the sp-hybridized phosphorus bases H-C[triple bond]P and H3C-C[triple bond]P as proton acceptors. These proton-bound complexes exhibit a variety of structural motifs, but all are stabilized by interactions that occur through the pi cloud of the acceptor base. The binding energies of these complexes range from 6 to 15 kcal/mol. Corresponding complexes with H3C-C[triple bond]P as the proton acceptor are more stable than those with H-C[triple bond]P as the acceptor, a reflection of the greater basicity of H3C-C[triple bond]P. In most complexes with sp2- or sp3-hybridized P-H donor ions, the P-H bond lengthens and the P-H stretching frequency is red-shifted relative to the corresponding monomers. Complex formation also leads to a lengthening of the C[triple bond]P bond and a red shift of the C[triple bond]P stretching vibration. The two-bond coupling constants 2pihJ(P-P) and 2pihJ(P-C) are significantly smaller than 2hJ(P-P) and 2hJ(P-C) for complexes in which hydrogen bonding occurs through lone pairs of electrons on P or C. This reflects the absence of significant s electron density in the hydrogen-bonding regions of these pi complexes.     

A shortcut to tris[2-(4-hydroxyphenyl)ethyl]phosphine oxide and 2-(4-hydroxyphenyl)ethylphosphinic acid via reaction of elemental phosphorus with 4-tert-butoxystyrene

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二氧化硅键合丙基哌-N-氨基磺酸作为可回收固体酸催化剂制备2-氨基-3-氰基-4-芳基-5,10-二氧代-5,10-二氢-4H-苯并[g]苯并吡喃和羟基取代的萘-1,4-二酮衍生物FahimeKhorami,HamidRezaShaterian简

An efficient method for the synthesis of 2-amino-3-cyano-4-aryl-5,10-dioxo-5,10-dihydro-4H-benzo[g]chromenes and hydroxy-substituted naphthalene-1,4-dione derivatives, using silica-bonded propylpiperazine-N-sulfamic acid as a solid acid, green, heterogeneous catalyst, under ambient and solvent-free conditions, is described. A simple procedure, high yields, short reaction time, safety, and reusability of the catalyst are advantages of these protocols.     

Synthesis and evaluation of 1-arylsulfonyl-3-piperazinone derivatives as factor Xa inhibitors IV. A series of new derivatives containing a spiro[5H-oxazolo[3,2-a]pyrazine-2(3H),4'-piperidin]-5-one skeleton

In the course of development of factor Xa (FXa) inhibitor in an investigation involving the synthesis of 1-arylsulfonyl-3-piperazinone derivatives, we found new compounds containing a unique spiro skeleton. Among such compounds, (-)-7-[(6-chloro-2-naphthalenyl)sulfonyl]tetrahydro-8a-(methoxymethyl)-1'-(4-pyridinyl)-spiro[5H-oxazolo[3,2-a]pyrazine-2(3H),4'-piperidin]-5-one (28, M55529) had activity more favorable than those of previously reported compounds. The inhibitory activity of M55529 for FXa is IC(50)=2 nM, with high selectivity for FXa over thrombin and trypsin.     

Short path to the synthesis of bi- and tricyclic compounds containing the 3-oxabicyclo[3.3.0]octene fragment from conjugated enynes by successive AdE reaction and [2+2+1]-cycloaddition

Conclusions A short general scheme was developed for the synthesis of a series of bi- and tricyclic compounds containing a 3-oxa-bicyclo[3.3.0]octane fragment on the basis of the successive acylallyloxylation of the double bond in the hexacarbonyldicobalt complexes of conjugated enynes and subsequent intramolecular [2+2+1]-cycloaddition.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 334–344, February, 1989.     

Synthesis and thermal properties of novel calix[4]arene derivatives containing 1,2,3-triazole moiety via K2CO3-catalyzed 1,3-dipolar cycloaddition reaction

Two calix[4]arene derivatives containing 1,2,3-triazole moiety were synthesized via K2CO3-catalyzed1,3-dipolar cycloaddition reaction between calix[4]arene-based azide and active methylene compounds in good yields.The structures of the two compounds synthesized herein were fully confirmed by 1HNMR,,（13）C NMR,and MS（ESI）.The thermal analysis showed that the mass losses of the synthesized compounds 4 and 5 containing 1,2,3-triazole groups are similar to each other.     

含磷拟除虫菊酯的研究I:3-[1'-磷(膦)酸酯基-2'-氯代乙烯基]-2,-二甲基环丙烷羧酸酯的合成及其几何异构体的研究

本文合成了九个新型的含磷拟除虫菊酯类化合物和五个新的中间体, 研究了亚磷(膦)酸酯的取代基空间位阻对Perkow重排产物中几何异构体的影响, 结果表明:取代基位阻增大, 产物E/Z比值也增大。     

Cyclocondensation of 3-amino-2-iminonaphtho[1,2-d]-thiazole with α-ketocarboxylic acid derivatives: Synthesis of 2-substituted 3-Oxo-3H-naphtho[1′,2′:4,5]thiazolo-[3,2-b][1,2,4]triazines as potential anti-HIV agents

The cyclocondensation of 3-amino-2-iminonaphtho[1,2-d]thiazole ( 1 ) with a series of α-keto mono- and dicarboxylic acid derivatives 5a-i under different conditions was investigated. When the experiments were performed by refluxing in glacial acetic acid, the corresponding cyclized products, 2-substituted 3-oxo-3H-naphtho[1′,2′:4,5]thiazolo[3,2-b][1,2,4]triazines 4 were obtained in fair to good yields. On the other hand, when the reaction was conducted in boiling ethanol, it gave only the open chain condensates 6 , or in rare cases, together with minor amount of 4 . Since the intermediates 6 exist as mixture of both E- and Z-isomers, cyclization through heating was found insufficient. In any event representative compounds 4b,g,i have been evaluated for anti-HIV activity, but none of them were active.     

Cyclic sulfur nitrogen compounds and phosphorus reagents: Part XII. Reactions of S4N4 with (2-pyridylamino) phosphines [1]

Tetrasulfurtetranitride, S₄N₄ reacts with (2-pyridylamino)-diphenylphosphine in MeCN at room temperature to form the cyclotrithiazene (NC₅H₄NH)-Ph₂PN S₃N₃ ( 1 ) in good yield. By contrast, the cyclophosphathiazenes Ph₂PS₂N₃ ( 2 ) and 1,5(Ph₂P)₂S₂N₄ ( 3 ) are isolated from the same reaction mixture under reflux conditions. In solution, compound 1 is found to be transformed into 2 . The reaction of S₄N₄ with (2-pyridylamino)phenyl(dicyclohexylamino)phosphine in MeCN at room temperature affords Ph(DCA)PS₂N₃ ( 4 ) (DCA = dicylohexylamino) as the only reaction product. This on treatment with norbornadiene produces the addition product Ph(DCA)PS₂N₃·C₇H₈ ( 5 ). The structure of 4 has been established by X-ray diffraction. Its PSN ring adopts a skew boat conformation with S N bond lengths varying from 1.574(4) to 1.606(4) Å. The mean value of the endocyclic P N bonds amounts to 1.618(3) Å.     

Flux synthesis of the noncentrosymmetric cluster compounds Cs2SnAs2Q9 (Q = S,Se) containing two different polychalcoarsenite beta-[AsQ4]3- and [AsQ5]3- ligands

Two noncentrosymmetric quaternary tin chalcoarsenates, Cs(2)SnAs(2)S(9) (1) and Cs(2)SnAs(2)Se(9) (2), were synthesized by the polychalcoarsenate flux method. Compound 1 crystallizes in the orthorhombic space group Pmc2(1) with a = 7.386(3) A, b = 14.614(5) A, c = 14.417(5) A, and Z = 4. Compound 2 crystallizes in the monoclinic space group P2(1) with a = 7.715(5) A, b = 17.56(1) A, c = 7.663(5) A, beta = 115.86(1) degrees, and Z = 2. Both structures contain the same tin-centered molecular cluster anions [Sn[AsQ(2)(Q(2))][AsQ(Q(2))(2)]](2)(-) (Q = S, Se) separated by Cs cations. The Sn(4+) ion is in a distorted octahedral environment coordinated by two different pyramidal-shaped tridentate ligands, [AsQ(2)(Q(2))](3)(-) and [AsQ(Q(2))(2)](3)(-). These compounds absorb visible light at energies above 1.98 and 1.45 eV for 1 and 2, respectively. Differential thermal analysis revealed that 1 melts at 350 degrees C and on cooling gives a glass. The glass recrystallizes at 268 degrees C upon subsequent heating. Compound 2 melts at 258 degrees C.