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In non-ferrous foundry, casting defects like microporosity and pin-hole porosity are due to expel of dissolved gases like hydrogen during solidification of castings from liquid stage to solid stage. These porosity defects significantly affect the strength and pressure tightness of the aluminum components. For a sound casting, the amount of dissolved gases present in the molten aluminum metal should be less. Degassing is a perfect process for removing dissolved gases from molten aluminum metal and its alloys. In this research, degassing of LM13, LM25, LM28, L99, and L155 was performed by passing nitrogen gas into rotary degassing chamber at different treatment time. The amount of H2 ml/100 g available in the aluminum alloys was measured after degassing by hydrogen gas analyzer and compared with the minimal value. Nitrogen degassing reduced the quantity of H2 ml/100 g less than the minimal value and made the aluminum alloys defect free.

A simple and convenient procedure is reported for the synthesis of mono- and 1,2-disubstituted hydrazines and tosylhydrazines by reduction of corresponding hydrazones, phenylhydrazones, azines, and tosylhydrazones by magnesium in methanol at ambient temperature.

A new series of benzoyl chloride-substituted 2,4-thiazolidinedione derivatives have been synthesized by the condensation of 2-amino-4-aryl-thiazole and 4′-chlorosulfonyl benzylidine-2,4-thiazolidinedione. New compounds were evaluated for their in vitro antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. Furthermore, new products were tested for in vitro antituberculosis activity against Mycobacterium tuberculosis using isoniazid and rifampicin as control drugs. The results of bioassay demonstrated that some of the newly synthesized 2,4-thiazolidinedione derivatives emerged as lead molecules with excellent MIC (mg/mL) values against mentioned organisms compared to standard drugs. The structure of the final analogs has been confirmed on the basis of IR, 1H NMR, mass spectral, and elemental analysis.

When provided individually, both the serotonin (5-HT(1A))-receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) and environmental enrichment (EE) enhance behavioral outcome and reduce histopathology after experimental traumatic brain injury (TBI). The aim of this study was to determine whether combining these therapies would yield greater benefit than either used alone. Anesthetized adult male rats received a cortical impact or sham injury and then were randomly assigned to enriched or standard (STD) housing, where either 8-OH-DPAT (0.1 mg/kg) or vehicle (1.0 mL/kg) was administered intraperitoneally once daily for 3 weeks. Motor and cognitive assessments were conducted on post-injury days 1-5 and 14-19, respectively. CA1/CA3 neurons and choline acetyltransferase-positive (ChAT(+)) medial septal cells were quantified at 3 weeks. 8-OH-DPAT and EE attenuated CA3 and ChAT(+) cell loss. Both therapies also enhanced motor recovery, acquisition of spatial learning, and memory retention, as verified by reduced times to traverse the beam and to locate an escape platform in the water maze, and a greater percentage of time spent searching in the target quadrant during a probe trial in the TBI + STD + 8-OH-DPAT, TBI + EE + 8-OH-DPAT, and TBI + EE + vehicle groups versus the TBI + STD + vehicle group (p ≤ 0.0016). No statistical distinctions were revealed between the TBI + EE + 8-OH-DPAT and TBI + EE + vehicle groups in functional outcome or CA1/CA3 cell survival, but there were significantly more ChAT(+) cells in the former (p = 0.003). These data suggest that a combined therapeutic regimen of 8-OH-DPAT and EE reduces TBI-induced ChAT(+) cell loss, but does not enhance hippocampal cell survival or neurobehavioral performance beyond that of either treatment alone. The findings underscore the complexity of combinational therapies and of elucidating potential targets for TBI.

(2007). OXIDATIVE CLEAVAGE OF 1, 2-DIOLS, α-KETOLS AND 1, 2-DIKETONES WITH AQUEOUS SODIUM HYPOCHLORITE. Organic Preparations and Procedures International: Vol. 39, No. 2, pp. 185-189.

A simple and convenient procedure is reported for the synthesis of mono- and 1,2-disubstituted hydrazines and tosylhydrazines by reduction of corresponding hydrazones, phenylhydrazones, azines, and tosylhydrazones by magnesium in methanol at ambient temperature.

The reaction of the tricarbadecaboranyl anion, 6-Ph-nido-5,6,9-C3B7H9-, with M(CO)5Br [M = Mn, Re] or [(η6-C10H8)Mn(CO)3+]BF4- yielded the half-sandwich metallatricarbadecaboranyl analogues of (η5-C5H5)M(CO)3 [M = Mn, Re]. For both 1,1,1-(CO)3-2-Ph-closo-1,2,3,4-MC3B7H9 [M = Mn (2) and Re (3)], the metal is η6-coordinated to the puckered six-membered open face of the tricarbadecaboranyl cage. Reactions of 2 and 3 with isocyanide at room temperature produced complexes 8-(CNBut)-8,8,8-(CO)3-9-Ph-nido-8,7,9,10-MC3B7H9 [M = Mn (4), Re (5)], having the cage η4-coordinated to the metal. Photolysis of 4 and 5 then resulted in the loss of CO and the formation of 1-(CNBut)-1,1-(CO)2-2-Ph-closo-1,2,3,4-MC3B7H9 [M = Mn, Re (6)], where the cage is again η6-coordinated to the metal. Reaction of 2 and 3 with 1 equiv of phosphine at room temperature produced the η6-coordinated monosubstituted complexes 1,1-(CO)2-1-P(CH3)3-2-Ph-closo-1,2,3,4-MC3B7H9 [M = Mn (7), Re (9)] and 1,1-(CO)2-1-P(C6H5)3-2-Ph-closo-1,2,3,4-MC3B7H9...

Interest has recently intensified in the search for molecular motors and actuators capable of delivering useful work to nanodevices under the control of electrochemical or photochemical power sources. While many of these man-made molecular machines are designed to deliver rectilinear motion, very few are proposed for the controlled delivery of rotary motion on the time scale characteristic of intramolecular rearrangements. The adaptation of commo-bis-dicarbollide metallacarborane structures to the possible design and synthesis of such rotary molecular motors is now under investigation. Progress toward this goal will be reported.

The boron-atom insertion reaction of nido-9,11-I(2)-7,8-C(2)B(9)H(9)(2-), with the HBCl(2):SMe(2) complex yields closo-4,7-I(2)-1,2-C(2)B(10)H(10), 1, in excellent yield. Although the two boron atoms (B3 and B6) nearest to the carbon atoms in 1 are equally available for attack by nucleophiles, the boron-degradation reaction of 1 with alkoxide ion occurs only at the B6 vertex, yielding regioselectively [(CH(3))(3)NH][nido-2,4-I(2)-7,8-C(2)B(9)H(10)], 2. The molecular structures of 1 and 2 have been determined by X-ray diffraction studies. Crystallographic data are as follows. For 1, monoclinic, space group P2(1)/n, a = 6.9199(19) Angstroms, b = 23.9560(7) Angstroms, c = 7.2870(2) Angstroms, beta = 94.081(4) degrees, V = 1204.9(6) Angstroms(3), Z = 4, rho(calcd) = 2.18 g cm(-3), R = 0.020, R(w) = 0.0610; for 2, orthorhombic, space group Pca2(1), a = 14.1141(7) Angstroms, b = 7.0276(4) Angstroms, c = 16.4602(9) Angstroms, V = 1632.7(15) Angstroms(3), Z = 4, rho(calcd) = 1.81 gcm(-3), R = 0.022, R(w) = 0.0623.

The syntheses and structural characterizations of the vanadium and niobium monohalide tricarbadecaboranyl complexes 1-(η5-C5H5)-1-Br-2-Ph-1,2,3,4-VC3B7H9 (1), [1-(η5-C5H5)-1,1‘-μ-Cl-2-Ph-closo-1,2,...

The reactions of nitriles (RCN) with arachno-4,6-C(2)B(7)H(12)(-) provide a general route to functionalized tricarbadecaboranyl anions, 6-R-nido-5,6,9-C(3)B(7)H(9)(-), R = C(6)H(5) (2(-)), NC(CH(2))(4) (4(-)), (p-BrC(6)H(4))(Me(3)SiO)CH (6(-)), C(14)H(11) (8(-)), and H(3)BNMe(2)(CH(2))(2) (10(-)). Further reaction of these anions with (eta(5)-C(5)H(5))Fe(CO)(2)I yields the functionalized ferratricarbadecaboranyl complexes 1-(eta(5)-C(5)H(5))-2-C(6)H(5)-closo-1,2,3,4-FeC(3)B(7)H(9) (3), 1-(eta(5)-C(5)H(5))-2-NC(CH(2))(4)-closo-1,2,3,4-FeC(3)B(7)H(9) (5), 1-(eta(5)-C(5)H(5))-2-[(p-BrC(6)H(4))(Me(3)SiO)CH]-closo-1,2,3,4-FeC(3)B(7)H(9) (7), 1-(eta(5)-C(5)H(5))-2-C(14)H(11)-closo-1,2,3,4-FeC(3)B(7)H(9) (9), and 1-(eta(5)-C(5)H(5))-2-H(3)BNMe(2)(CH(2))(2)-closo-1,2,3,4-FeC(3)B(7)H(9) (11). Reaction of 11 with DABCO (triethylenediamine) resulted in removal of the BH(3) group coordinated to the nitrogen of the side chain, giving 1-(eta(5)-C(5)H(5))-2-NMe(2)(CH(2))(2)-closo-1,2,3,4-FeC(3)B(7)H(9) (12). Crystallographic studies of complexes 3, 5, 7, 9, and 11 confirmed that these complexes are ferrocene analogues in which a formal Fe(2+) ion is sandwiched between the cyclopentadienyl and tricarbadecaboranyl monoanionic ligands. The metals are eta(6)-coordinated to the puckered six-membered face of the tricarbadecaboranyl cage, with the exopolyhedral substituents bonded to the low-coordinate carbon adjacent to the iron.

A simple and convenient procedure for the rapid oxidation of a variety of selenides, selenoxides, tellurides, and telluroxides with aqueous sodium hypochlorite to selenones and tellurones, respectively, has been reported in dimethylformamide at ambient temperature.

A simple and convenient procedure is reported for the synthesis of benzils and aliphatic 1,2-diketones of cyclic and open chain compounds from corresponding hydrobenzoins and 1,2-diols by refluxing with N-bromosuccinimide in carbon tetrachloride in presence or absence of pyridine.

Vanada- and niobatricarbadecaboranyl monohalide complexes proved to be potent cytotoxic agents against murine and human leukemia and lymphoma growth as well as HeLa suspended uterine carcinoma. The vanada complex reduced the growth of KB nasopharynx, Hepe liver, HCT-8 ileum and 1-A9 ovary solid carcinomas. A mode of action study in human HL-60 promyelocytic leukemia cells showed that DNA and purine de novo syntheses were significantly inhibited with suppression of the regulatory enzymes activities of DNA polymerase α and PRPP-amido transferase. There was moderate inhibition of RNA synthesis and m-RNA polymerase activity. These complexes did not inhibit human topoisomerase I or II activity, although the niobium complex nicked the DNA. The complexes did activate caspases 3, 6 and 9 which are linked to apoptosis programmed cell death. These vanada- and niobatricarbadecaboranyl monohalide complexes appear to be more specific in their effects on leukemia cell metabolism than other sandwich complexes which have broad effects on multiple enzymes.

The tricarbadecaboranyl anions, 6-R-nido-5,6,9-C3B7H9- (R = CH3 or C6H5), have been employed to produce a series of metallatricarbadecaboranyl analogues of the group VIII metallocenes, (η5-C5H5)2M,...

The synthesis and X-ray diffraction study of 3-(2-biphenyl)-1,2- C2B10H11, 1, provides an example of an intramolecular non-classical C–H⋯π hydrogen bonding interaction in which the same aromatic π-electron-donating group which interacts with the carborane C–H is also connected to the carborane cage.

A simple procedure is reported for the stereoselective debromination of vic-dibromides with nickel boride at ambient temperature. Debromination with concomitant reduction of vic-dibromides to give dihydro products in a one-pot reaction is also reported. α,β-Dibromoketones can also be converted to their corresponding alcohols.Key words: debromination, vic-dibromides, stereoselective, reduction, E-alkenes.