Facile one-pot synthesis of functionalized organophosphonate esters via ketone insertion into bulky arylphosphites

The reaction of phosphorus trichloride with 2,6-diisopropyl phenol in the presence of LiCl under reflux conditions for 24 h produces a mixture of (ArO)PCl2 and (ArO)2PCl (Ar = 2,6-iPr2C6H3). The hydrolysis of the aryloxy compounds in acetone/H2O results in the formation of two novel phosphonate ester derivatives [(ArO)P(O)(OH)(CMe2OH)] (1) and [(ArO)2P(O)(CMe2OH)] (2), respectively in a moderate yield. The title compounds have presumably formed via acetone insertion to the P-H bonds of (ArO)P(O)(H)(OH) and (ArO)2P(O)(H), respectively, in the presence of HCl produced during the hydrolysis. Compounds 1 and 2 have been characterized by elemental analysis, and ESI-mass, Infrared and NMR spectroscopic techniques. Further, solid state structures of 1 and 2 have been established by single crystals X-ray diffraction studies

Bitter Gourd (Momordica charantia) Peroxidase in Decolorization of Dyes from Tannery Effluent

Bitter Gourd (Momordica charantia) is a commonly available plant in India and its applications are limited to few medicinal properties in addition to being edible. The primary objective of this study is to evaluate the efficacy of Momordica charantia peroxidase in the degradation of dyes present in tannery effluents under various experimental conditions like pH, Temperature, Time intervals and Enzyme concentration on the basis of the one-factor-at-a-time (OFAT) method. The maximum decolorization was achieved at pH 5.0 – 6.0, 40oC temperature, in 4 hours with an enzyme concentration of 0.6 ml consisting of 4500 Units enzyme activity extracted from 0.5 g of Bitter Gourd. Present study results demonstrate that the Momordica charantia peroxidase is an effective biocatalyst for the treatment of effluents with dyes from tanning industries.ÂÂ

Penerapan Model Pembelajaran Atraktif Berbasis Multiple Intelligences Tentang Pemantulan Cahaya pada Cermin

Penelitian ini bertujuan untuk mengetahui efektivitas penerapan model pembelajaran atraktif berbasis multiple intelligences dalam meremediasi miskonsepsi siswa tentang pemantulan cahaya pada cermin. Pada penelitian ini digunakan bentuk pre-eksperimental design dengan rancangan one group pretest-post test design. Alat pengumpulan data berupa tes pilihan ganda dengan reasoning. Hasil validitas sebesar 4,08 dan reliabilitas 0,537. Siswa dibagi menjadi lima kelompok kecerdasan, yaitu kelompok linguistic intelligence, mathematical-logical intelligence, visual-spatial intelligence, bodily-khinestetic intelligence, dan musical intelligence. Siswa membahas konsep fisika sesuai kelompok kecerdasannya dalam bentuk pembuatan pantun-puisi, teka-teki silang, menggambar kreatif, drama, dan mengarang lirik lagu. Efektivitas penerapan model pembelajaran multiple intelligences menggunakan persamaan effect size. Ditemukan bahwa skor effect size masing-masing kelompok berkategori tinggi sebesar 5,76; 3,76; 4,60; 1,70; dan 1,34. Penerapan model pembelajaran atraktif berbasis multiple intelligences efektif dalam meremediasi miskonsepsi siswa. Penelitian ini diharapkan dapat digunakan pada materi fisika dan sekolah lainnya

Octameric and decameric aluminophosphates

The title compounds are not only among the largest molecular aluminophosphates synthesized thus far, but are also rare polyhedral cages that contain AlO4, AlO5, and AlO6 coordination geometries (see structure; red O, blue Al, pink P). The cores of these aluminophosphates represent new structural building units (SBUs) in zeolite chemistry

Water in organoaluminum chemistry! Three-in-one aluminophosphate clusters that incorporate boehmite repeating units

Mix and match! Slow introduction of water in the reaction between a monoaryl phosphate and an aluminum alkyl or Al2Cl6 leads to the formation of three-in-one clusters, which constitute aluminophosphate and aluminum hydroxide moieties within the same molecules (see graphic, C and H atoms not shown). Impeding the attack of water by kinetically stabilizing the aluminum alkyl leads to the isolation of a dimeric aluminophosphate, which throws mechanistic insights into the formation of larger clusters

RNA interference in Pratylenchus coffeae: knock down of Pc-pat-10 and Pc-unc-87 impedes migration

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Structural diversity in organotin compounds derived from bulky monoaryl phosphates: dimeric, tetrameric, and polymeric tin phosphate complexes

Monoaryl phosphates with a bulky aryl substituent have been used to synthesize new organotin clusters and polymers. The equimolar reaction between 2,6-diisopropylphenylphosphate (dipp-H2) and Me2SnCl2 in ethanol at 25 °C leads to the formation of [Me2Sn(μ3-dipp)]n (1), while the reaction of 2,6-dimethylphenylphosphate (dmpp-H2) with Me2SnCl2 in either a 1:1 or 2:1 molar ratio proceeds to produce exclusively [Me2Sn(μ-dmpp-H)2]n.nH2O (2). Compounds 1 and 2 are 1D polymers with different architectures. In compound 1, the tin atom is five-coordinate (trigonal bipyramidal). Each dipp ligand bridges three different tin atoms to form an infinite ladder-chain structure. In 2, each six-coordinate (octahedral) tin atom is surrounded by four phosphate oxygen atoms originating from four different bridging dmpp-H ligands, thus forming a spirocyclic coordination polymeric chain. The use of nBu2SnO as the diorganotin source in its reaction with dipp-H2 leads to the isolation of dimeric [nBu2Sn(μ-dipp-H)(dipp-H)]2 (4), which contains a central Sn2O4P2 unit. There are two chemically different half molecules of 4 in the asymmetric part of the unit cell and hence it actually exists as a 1:1 mixture of [nBu2Sn(μ-dipp-H)(dipp-H)]2 and [nBu2Sn(μ-dipp)(dipp-H2)]2 in the solid state. The reaction of the monoorgano tin precursor nBuSn(O)(OH)·xH2O with dipp-H2 takes place in acetone at room temperature to yield the tetrameric cluster 5, which has different structures in the solution and in the solid state. 31P NMR spectroscopy clearly suggests that 5 has the formula [nBu4Sn4(μ-O)2((μ-dipp-H)8] in solution. The single-crystal X-ray diffraction studies in the solid state, however, reveal that compound 5 exists as [nBu4Sn4(μ-OH)2(μ-dipp-H)6(μ-dipp)2]. The use of compounds 1-4 as possible precursors for the preparation of ceramic tin phosphate materials has been investigated. The thermolysis of 1 at 500 °C leads to the formation of quantitative amounts of Sn2P2O7, while the thermolysis of 2, 3, and 4 under similar conditions results in the formation of SnP2O7

A Sustainable Approach for Graphene Oxide‐supported Metal N‐ Heterocyclic Carbenes Catalysts

Sustainable noble metal-N-heterocyclic carbenes (NHC's) are a topic of arising concern in both the chemical industry and the academic community due to a growing consciousness of environmental pollution and scarcity. Recovering and reusing homogeneous catalysts from the reaction mixture requires a tremendous amount of capital investment in the chemical manufacturing industry. Heterogeneous catalysts are proved to have better functional groups tolerance; however, catalysts support largely influences the active catalyst sites to affect catalyst efficiency and selectivity. Thus the, choice of catalyst supports plays an almost decisive role in this emerging area of catalysis research. Graphene oxide (GO)/reduced graphene oxide (rGO) support has a potential growth in heterogeneous catalysis owing to their commercial availability, considerably larger surface area, inert towards chemical transformations, and easy surface functionalization to attached metal complexes via covalent and non-covalent aromatic π-conjugates. To take advantage of two independently well-established research areas of noble metal-N-heterocyclic carbenes and GO/rGO support via covalent or non-covalent interactions approach would offer novel heterogeneous complexes with improved catalytic efficiency without sacrificing product selectivity. This unique concept of marrying metal-N-heterocyclic carbenes with GO/rGO support has potential growth in the chemical and pharmaceutical industry, however, limited examples are reported in the literature. In this perspective, a comprehensive summary of metal−NHC synthesis on GO/rGO support and synthetic strategies to graft M−NHC onto GO/rGO surface, catalytic efficiency, for the catalytic transformation are critically reviewed. Furthermore, a plausible mechanism for non-covalent grafting methodology is summarized to direct readers to give a better understanding of M−NHC@rGO complexes. This would also allow the designing of engineered catalysts for unexplored catalytic applications