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Reactions of [PdCl2(COD)] with 1 equiv. of the iminophosphorane-phosphine ligands Ph2PCH2P{NP(O)(OR)2}Ph2 (R = Et 1, Ph 2) lead to the novel Pd(II) derivatives cis-[PdCl2(κ2-(P,N)-Ph2PCH2P{NP(O)(OR)2}Ph2)] (R = Et 3, Ph 4). Pd–N bond cleavage readily takes place upon treatment of these species with a variety of two-electron donor ligands. By this way, complexes cis-[PdCl2(κ1-(P)-Ph2PCH2P{NP(O)(OR)2}Ph2)(L)] (R = Et, L = CNtBu 5a, CN-2,6-C6H3Me25b, py 5c, P(OMe)35d, P(OEt)35e; R = Ph, L = CNtBu 6a, CN-2,6-C6H3Me26b, py 6c, P(OMe)36d, P(OEt)36e) have been synthesized in high yields. The addition of two equivalents of ligands 1/2 to dichloromethane solutions of [PdCl2(COD)] results in the formation of complexes trans-[PdCl2(κ1-(P)-Ph2PCH2P{NP(O)(OR)2}Ph2)2] (R = Et 7, Ph 8), which can be converted into the dicationic species [Pd(Ph2PCH2P{NP(O)(OR)2}Ph2)2][SbF6]2 (R = Et 9, Ph 10) by treatment with AgSbF6. Complex 10 also reacts with CNtBu to afford trans-[Pd(κ1(P)-Ph2PCH2P{NP(O)(OPh)2}Ph2)2(CNtBu)2][SbF6]211. The structures of 4, 5b, 7 and 9 have been determined by single-crystal X-ray diffraction methods. In addition, the ability of these Pd(II) complexes to promote the catalytic cycloisomerization of (Z)-3-methylpent-2-en-4-yn-1-ol into 2,3-dimethylfuran has also been studied.

Haloethanoic (haloacetic) acids are formed during chlorination of drinking water and are regulated by the Environmental Protection Agency (EPA). These compounds are normally quantified by gas chromatography with electron capture detection (GC-ECD) as the methyl esters. EPA Method 552 uses diazomethane (CH2N2) for this purpose, but has only been validated by EPA for HAA6: chloro-, dichloro-, bromo-, dibromo-, bromochloro- and trichloroacetic acids. EPA Method 552.2 was developed and validated for all nine analytes (HAA9 = HAA6 + dibromochloro-, bromodichloro- and tribromoethanoic acids). Since the promulgation of Method 552.2, which uses acidic methanol, a debate has ensued over discrepancies observed by various laboratories when using diazomethane instead. In an effort to identify and eliminate potential sources for these discrepancies, a comparative study was undertaken for HAA9. Better accuracy and precision were observed for all HAA9 species by Method 552.2; recoveries were satisfactory in de-ionized and tap water. Method 552 remains satisfactory for HAA6. Systematic differences in instrumental response are observed for the two methods, but these are precise and may be accounted for using similarly treated standards and analyte-fortified (spiked) samples. That notwithstanding, Method 552 (CH2N2) was shown to be unsuitable for dibromochloro-, bromodichloro- and tribromoethanoic acids (HAA9-6). The primary problem appears to be a photoactivated reaction between diazomethane and the HAA9-6 analytes; however, side reactions were found to occur even in the dark. Analyte loss is most pronounced under typical laboratory lighting (white F40 fluorescent lamps + sunlight), but it is also observed under Philips gold F40 lamps (lambdaor = 520 nm), and in the dark.

A flexible nanofiber-based electrode material is proposed as cathode in a vanadium-based flow battery (VRFB), allowing the design of innovative VRFB configuration geometries. Its estimated electrochemical surface area is 350 cm2 cm−3, doubling that of commercial PAN-felt.

An oriented attachment and growth mechanism allows an accurate control of the size and morphology of Cu(2-x)S nanocrystals, from spheres and disks to tetradecahedrons and dodecahedrons. The synthesis conditions and the growth mechanism are detailed here.

The reactivity of complex [Ru(η6-p-cymene)(κ3P,N,O-Ph2PCH2P{NP(O)(OEt)2}Ph2)][SbF6]21 towards a variety of mono- and bidentate neutral ligands has been studied, allowing the high-yield synthesis of the novel half-sandwich Ru(II) derivatives [Ru(η6-p-cymene)(L)(κ2P,O-Ph2PCH2P{NP(O)(OEt)2}Ph2)][SbF6]2 (L = NCMe 3a, NCEt 3b, PMe34a, PMe2Ph 4b, PMePh24c, PPh34d, P(OMe)35a, P(OEt)35b, P(OPh)35c, py 6, κ1P-dppm 7a, κ1P-dppe 7b), as well as the octahedral species [Ru(N⁁N)2(κ2P,O-Ph2PCH2P{NP(O)(OEt)2}Ph2)][SbF6]2 (N⁁N = bipy 8a, phen 8b). Deprotonation of complexes 8a,b, upon treatment with an excess of NaOH in CH2Cl2, generates the monocationic derivatives [Ru(N⁁N)2(κ2P,N-Ph2PC(H)P{NP(O)(OEt)2}Ph2)][Cl] (N⁁N = bipy 9a, phen 9b) in which the methanide anion adopts an unprecedented κ2P,N bidentate coordination mode. The structures of compounds 6, 8a and 9a have been determined by single-crystal X-ray diffraction methods.