Direct preparation of monoarylidene derivatives of aldehydes and enolizable ketones with DIMCARB

[reaction: see text] Aryl alpha,beta-unsaturated ketones and aldehydes were synthesized, in moderate to excellent yields, with use of dimethylammonium dimethyl carbamate (DIMCARB) as a recyclable reaction medium and as a catalyst.     

On the system of functional equationsf(x + y) = f(x) + f(y) andf(xy) = p (x)f(y) + q(y)f(x)

Aequationes mathematicae -     

Solid State Structures and Solution Dynamics of Unsolvated and Diethyl Ether Solvated Dilithium N,N'-Bis(trimethylsilyl)ethylenediamide Complexes

The lithiation of N,N'-bis(trimethylsilyl)ethylenediamine, 1, by 2 equiv of methyllithium in diethyl ether yields the dimeric diethyl ether adduct [{Li[N(SiMe(3))CH(2)CH(2)NSiMe(3)]Li.OEt(2)}(2)], 2. Recrystallization of 2 from benzene gives quantitatively the unsolvated trimer [{Li[N(SiMe(3))CH(2)CH(2)NSiMe(3)]Li}(3)], 3. The solution dynamics of 2 and 3 in toluene have been investigated using variable temperature multinuclear NMR spectroscopy. In solution, 2 is undergoing a rapid exchange process involving an equilibrium between unsolvated and diethyl ether solvated dimers, whereas compound 3 exists in a temperature dependent equilibrium of dimeric and trimeric species, of which the trimer is fluxional and exchanges inequivalent ligands by an intramolecular distortion of the Li(6)N(6) cage structure. Crystals of 2 are monoclinic, of space group P2(1)/n (No. 14), with a = 10.692(9) ?, b = 16.192(2) ?, c = 24.04(4) ?, beta = 101.16(5) degrees, V = 4083(8) ?(3), and Z = 4. Crystals of 3 are trigonal, of space group R&thremacr;m(No. 166), a = 17.765(1) ?, c = 13.394(1) ?, V = 3660.5(5) ?(3), Z = 3.     

Vortex fluidic exfoliation of graphite and boron nitride

Graphite is exfoliated into graphene by shearing vortex fluidic films of N-methyl-pyrrolidone (NMP), as a controlled process for preparing oxide free graphene, and for exfoliating the corresponding boron nitride sheets.     

Lanthanide crown ether complexes of p-sulfonatocalix[5]arene

Two types of arrays are formed in water involving aza-crown ethers, p-sulfonatocalix[5]arene and europium(III) ions. One is a co-ordination polymer connecting calixarenes, sodium ions and lanthanide ions based on "ferris wheel" moieties incorporating aza-18-crown-6 and sodium ions. The second structure is a host-guest arrangement with di-protonated diaza-18-crown-6 in the cavity of the calixarenes as part of secondary coordination spheres of aquated europium(iii) ions.     

Towards benign syntheses of bipyridines: versatile approach to supramolecular building blocks

Chiral and achiral bipyridines are readily accessible via a solvent-free Michael addition involving solid NaOH, followed by treatment with ammonium acetate in acetic acid, as a ‘one pot’ more benign protocol, affording pure products in high yield, typically >80%.     

Unraveling the relationship between structure and stabilization of triarylpyridines as G-quadruplex binding ligands

A series of novel 2,4,6-triarylpyridines have been synthesized and their interactions with intramolecular G-quadruplexes have been measured by F?rster Resonance Energy Transfer (FRET) melting and Fluorescent Intercalator Displacement (FID) assays. A few of these compounds exhibit stabilization of G4-DNA that is comparable to other benchmark G4-DNA ligands with fair to excellent G4-DNA vs. duplex selectivity and significant cytotoxicity towards HeLa cells. The nature of the 4-aryl substituents along with side chain length governs the G4-DNA stabilization ability of the compounds. In addition, we demonstrate that there is a strong correlation between the ability of the compounds to stabilize the same G4-DNA sequence in K(+) and Na(+) conditions and a strong correlation between the ability of the compounds to stabilize different G4-DNA sequences in K(+) or Na(+) buffer.     

Pd-induced ordering of 2D Pt nanoarrays on phosphonated calix[4]arenes stabilised graphenes

p-Phosphonic acid calix[4]arenes render high stability to exfoliated graphenes in water. These calix[4]arenes modified graphenes can be used as highly effective substrates to nucleate ultra-small Pd nanoparticles, which in turn serve as galvanic reaction templates for the generation of high density 2D arrays of Pt nanoparticles.     

Solvent and hydrogen confinement in molecular capsules-Hirshfeld surface and molecular simulation analysis

Hirshfeld surface analysis of the 'ordered' inner phase of the molecular capsule complex, [(chloroform)(6)@C-n-butylpyrogallol[4]arene)(6)], provides insight into the intermolecular contacts and orientation of the solvent molecules. Molecular simulations show that adding two or three hydrogen molecules to the six solvent molecules is energetically favoured, and this correlates with NMR studies.