The coordination modes of the [Au(PPh3)](+) cation to metal alkynyl complexes have been investigated. On addition to ruthenium, a vinylidene complex, [Ru(η(5)-C5H5)(PPh3)2([double bond, length as m-dash]C[double bond, length as m-dash]CPh{AuPPh3})](+), is obtained while addition to a gold(iii) compound gives di- and trinuclear gold complexes depending on the conditions employed. In the trinucle...

Detailed models are presented for the triple-stranded polynucleotide helices of poly (U)-poly (A)-poly (U) (two forms), poly (U)-poly d (A) -poly (U), poly d(C)-poly d(I)-poly d(C), poly d(T)-polyd(A)-poly d(T) and poly (I)-poly (A)-poly (I). The models were genrated using a computerized, linked-atom procedure which preserves standard bond lengths, bond anglesand sugar ring conformations, const...

The reaction of the organogold metallaligand [(AuC[triple bond]Cbpyl)(2)(mu-Ph(2)P(CH(2))(4)PPh(2))] (bpyl = 2,2'-bipyridin-5-yl) with Fe(2+) or Zn(2+) ions gave helicates where the three ligand strands adopt a unique looped geometry.

We report the formation of a highly unusual fused, tricyclic purine derivative via N3 alkylation of 9-propargyladenine, upon activation of the acetylenic triple bond by Ag(I) ions. The participation of silver ions in this process might offer newer design paradigms for minor groove N3 DNA alkylation, antibacterial and anticancer agents.

Grafting of [W(2)(NMe(2))(6)] onto dehydroxylated silica affords the well-defined surface species [([triple bond, length as m-dash]Si-O)W(2)(NMe(2))(5)], characterized by elemental analysis, and infrared, Raman and NMR spectroscopies, and the catalytic reactivity of this supported tungsten(III) d(3)-d(3) dimer and of its alkoxide derivatives towards alkynes has been probed.

New compound Zn[(S,S)-iPr-pybox](Et)(2) (1) was fully characterized, including by X-ray diffraction structural studies. Its grafting onto partially dehydroxylated silica affords material 2, which bears well-defined chiral ([triple bond]SiO)Zn[(S,S)-iPr-pybox](Et) sites. Hybrid material 2 displays significantly better catalytic performances than 1 in enantioselective silylcyanation, thus demonst...

Chromate (CrVI) reduction by sulfide was conducted in anaerobic batch experimental systems. The molar ratio of the reduced CrVI to the oxidized S(-II) was 1:1.5 during the reaction, suggesting that the product of sulfide oxidation was elemental sulfur. Under the anaerobic condition, the reaction was pseudo first order initially with respect to CrVI, but the rate was dramatically accelerated at ...

The structures of the mononuclear derivatives HMn(CO)n (n=4 and 3) are shown by density functional theory (B3LYP and PB86) to derive from octahedral HMn(CO)5 by losses of various combinations of carbonyl groups with relatively little change in the C-Mn-C angles involving the remaining carbonyl groups. The binuclear H2Mn2(CO)n structures are predicted to have bridging hydrogen atoms in preferenc...

Three computational methods (M06-2X/Def2-TZVP, B3PW91/Def2-TZVP and B3LYP/LANL2DZ+dp) were used to study the effect of substitution on the potential energy surfaces of RTl≡PR (R = F, OH, H, CH₃, SiH₃, SiMe(SitBu₃)₂, SiiPrDis₂, Tbt (=C₆H₂-2,4,6-(CH(SiMe₃)₂)₃), and Ar* (=C₆H₃-2,6-(C₆H₂-2, 4,6-i-Pr₃)₂)). The theoretical results show that these triply bonded RTl≡PR compounds have a preference for a...

There is currently tremendous interest in the previously documented example of a stable species exhibiting a boron-boron triple bond (Science, 2012, 336, 1420). Notably, it has recently been stated using arguments based on force constants that this diboryne may not, in reality, feature a boron-boron triple bond. Here, we use advanced solid-state NMR and computational methodology in order to dir...