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We report here a new route for the preparation of [1,1′‐bis(o‐carboranyl)]borane, a 3D analogue of 9‐borafluorene, η2‐σ‐silane adduct (1‐H‐SiEt3) in high yields (>80 %). The nature of B−H−Si bonding was studied by density functional theory (DFT) computations. Preliminary reactivity study of 1‐H‐SiEt3 with small molecules was carried out. Interestingly, 1‐H‐SiEt3 reacts with benzophenone in hexane producing the deoxygenation product Ph2CH2. While in benzene, 1‐H‐SiEt3 reacts with benzophenone leading to mixture of Ph2CH2 and Ph3CH (3 : 1). Ph3CH is formed via addition of benzene to the carbonyl followed by deoxygenation. In contrast, the reaction of benzophenone with Et3SiH in presence of a catalytic amount of 1‐H‐SiEt3 leads to hydrosilylation product Ph2(H)C−OSiEt3. [ABSTRACT FROM AUTHOR]

In this work the first examples of C–N bond activation by insertion into a geometrically constrained PIII-centre are shown. The mechanisms of these activation processes leading to new PV species were studied both experimentally and computationally. Interestingly, in the case of insertion of the PIII-centre into an N–C(O)H bond, an unstable phosphoranyl-formaldehyde intermediate is probably formed, which undergoes decarbonylation in the presence of a catalytic amount of HCl producing a hydrophosphorane. [ABSTRACT FROM AUTHOR]

An air‐stable dicationic Zn2+ complex (1) in a tripod‐type ligand with non‐bound phosphorus base and three pyridinyl "arms" (TPPh) was synthesized. Remarkably, while 2 mol% of 1 at room temperature selectively catalyzed dehydrogenative borylation of terminal alkynes with HBPin, a lower loading of 1 (0.5 mol%) at 90 °C selectively promoted hydroboration reaction of the same alkynes skipping the dehydrogenative borylation step. The mode of action of 1 was proposed based on experimental observations as well as the mechanism of dehydrogenative borylation was studied by DFT computations. [ABSTRACT FROM AUTHOR]

A 90 days study was undertaken to evaluate the effect of green tea (Camellia sinensis) on disease resistance and hematology of common carp (Cyprinus carpio). The test diets was prepared by incorporating green tea powder at 0.5, 1, 1.5 and 2 g/kg basal diet. The hemato-biochemical indices were examined before and after fish were challenged against Aeromonas hydrophila pathogen containing 3.16 × 107 CFU/ml. There were significantly higher number of erythrocytes, leucocytes, haemoglobin value in pre challenge. Leucocytes significantly increased (p < 0.05) in both pre and post challenge. The serum protein content was significantly (p < 0.05) increased for fish fed with 1 g/kg green tea. However, feeding of green tea incorporated diet resulted reduction in serum glucose, serum magnesium and serum cholesterol level in fish. No mortality was observed in 1 g/kg and 1.5 g/kg green tea incorporated diet fed fishes after challenged against Aeromonas hydrophila. These results indicated that green tea leaf powder stimulates the immunity and makes common carp more resistant to bacterial infection (A. hydrophila). [ABSTRACT FROM AUTHOR]

A 90 days study was undertaken to evaluate the effect of green tea (Camellia sinensis) on growth and survival of common carp (Cyprinus carpio). The test diets was prepared by incorporating green tea powder at 0.5, 1, 1.5 and 2 g/kg basal diet. The fish fed with 1.5 g/kg green tea (Camellia sinensis) incorporated diet significantly improved (p < 0.05) weight gain, specific growth rate, feed conversion ratio compared to control. These results indicated that green tea leaf powder at 1.5 g/kg diet improved the growth performance of common carp compare to control and other treatment group. The survival of the fish was 100 percent in all treatment and control group. Likewise, the impact of green tea has shown effective therapeutic results to consider incorporating this plant in fish feed to replace the use of antibiotics or therapeutics for sustainable aquaculture. [ABSTRACT FROM AUTHOR]

An attempt was made to study the hooking efficiency, hooking location and injury pattern of two widely operated hook types that were used in study area. The study was conducted in two selected sites of Dhamtari district of Chhattisgarh, that was “Rudri barrage” of Mahanadi river and its basin. Straight shank “J” hook of number 14 size (ADDYA fish hook manufacturer) and Kirby bend J-hook of number 14 size (ADDYA fish hook manufacturer) were used to assess the fishing performances. Total 60 hand line operations were targeted for catfishes like Clarius batrachus, Heterpneustes fossilis and some other Channa sp. By evaluating the CPUE of both the hooks results illustrated that the Kirby bend J hook was much more efficient than the normal J hook. The (CPUE) of normal J hook were 33.3 kg, while the Kirby bend hook had CUPE of 43.3 kg. In contrast straight shank J-hooks had 70% of lip hooking, 30% of throat hooking and there was no deep hooking, while in case of Kirby bend hook 69.2% were lip hooked, 15.3% were throat hooked and 7.6% were deep hooked. In straight shank Jhooks the severity of injury observed was 30% as minor, 50% moderate and 10% of severe injury. On the other hand, total 26 fishes caught by Kirby bend hooksrecorded 38.4% of minor, 30% of moderate and 7.6% of severe injury. Live baits, like earthworm and crickets were used on both the hook types. [ABSTRACT FROM AUTHOR]

We have demonstrated stepwise functionalization of chlorophosph(III)azane, [ClP(μ-NtBu)]2 with organic azides and chalcogens (S and Se). The in situ 31P{¹H} NMR spectroscopic investigations reveal that conversion of the basic PIII2N2 framework, leading to PV 2N2 proceeds via (PIII/PV)N2 intermediates. Under controlled conditions, the (PIII/PV)N2 intermediate species can be isolated, providing details of the reaction pathway and distribution of the cis and trans isomers of the PV2N2 products. It has also been demonstrated that neat reactions at elevated temperatures expedite the formation of PV2N2 products, without significantly affecting the yields and relative distribution of the cis and trans isomers. All new compounds reported here are potential building blocks for the assembly of inorganic macrocycles and polymers. [ABSTRACT FROM AUTHOR]

In this work the first examples of C-N bond activation by insertion into a geometrically constrained P III -centre are shown. The mechanisms of these activation processes leading to new P V species were studied both experimentally and computationally. Interestingly, in the case of insertion of the P III -centre into an N-C(O)H bond, an unstable phosphoranyl-formaldehyde intermediate is probably formed, which undergoes decarbonylation in the presence of a catalytic amount of HCl producing a hydrophosphorane.

Hydrosilylation of C[double bond, length as m-dash]C double and C[triple bond, length as m-dash]C triple bonds is one of the most widely used processes in organosilicon chemistry, mostly catalyzed by Pt-based complexes. We report here the synthesis of an air-stable dicationic Zn2+-based complex in a hemilabile tris(2-methyl-6-pyridylmethyl) phosphine (TmPPh) ligand, 12+[B(C6F5)4]2. When heated, 12+[B(C6F5)4]2 activates Si-H bonds reversibly via ligand/metal cooperation between Lewis acidic Zn2+ and Lewis basic N centers in a frustrated Lewis pair (FLP) type fashion. Consequently, 12+[B(C6F5)4]2 was found to be an effective catalyst for hydrosilylation reactions of C[double bond, length as m-dash]C double and C[triple bond, length as m-dash]C triple bonds. Remarkably, these hydrosilylation reactions can be loaded under aerobic conditions, as well as, in some cases, work under neat conditions. The mechanism of the activation of the Si-H bond and the hydrosilylation reaction is proposed based on experiments and density functional theory (DFT) calculations.

Reactions of bis(phosphinimino)amines LH and L'H with Me2 S⋅BH2 Cl afforded chloroborane complexes LBHCl (1) and L'BHCl (2), and the reaction of L'H with BH3 ⋅Me2 S gave a dihydridoborane complex L'BH2 (3) (LH=[{(2,4,6-Me3 C6 H2 N)P(Ph2 )}2 N]H and L'H=[{(2,6-iPr2 C6 H3 N)P(Ph2 )}2 N]H). Furthermore, abstraction of a hydride ion from L'BH2 (3) and LBH2 (4) mediated by Lewis acid B(C6 F5 )3 or the weakly coordinating ion pair [Ph3 C][B(C6 F5 )4 ] smoothly yielded a series of borenium hydride cations: [L'BH](+) [HB(C6 F5 )3 ](-) (5), [L'BH](+) [B(C6 F5 )4 ](-) (6), [LBH](+) [HB(C6 F5 )3 ](-) (7), and [LBH](+) [B(C6 F5 )4 ](-) (8). Synthesis of a chloroborenium species [LBCl](+) [BCl4 ](-) (9) without involvement of a weakly coordinating anion was also demonstrated from a reaction of LBH2 (4) with three equivalents of BCl3 . It is clear from this study that the sterically bulky strong donor bis(phosphinimino)amide ligand plays a crucial role in facilitating the synthesis and stabilization of these three-coordinated cationic species of boron. Therefore, the present synthetic approach is not dependent on the requirement of weakly coordinating anions; even simple BCl4 (-) can act as a counteranion with borenium cations. The high Lewis acidity of the boron atom in complex 8 enables the formation of an adduct with 4-dimethylaminopyridine (DMAP), [LBH⋅(DMAP)](+) [B(C6 F5 )4 ](-) (10). The solid-state structures of complexes 1, 5, and 9 were investigated by means of single-crystal X-ray structural analysis., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)