The effect of carbon is subtle but sweet : The flexible C‐linkage in the newly synthesised C‐glycosyl mimetic, Manα(1,6)‐C‐ManαOPh allows OH? π bonding, both in the gas phase and in aqueous solution. This interaction is absent in the O‐linked disaccharide (see figure).
Single‐site catalysts : Syndiospecific styrene polymerization promoted by single‐site ansa‐lanthanidocene catalysts proceeds selectively in a secondary (2,1) fashion, both at the initiation and propagation steps. The steric hindrance between the phenyl ring of the incoming styrene monomer and the ancillary ligands (Cp′, Flu′), induced by the change of either the bridge or the “active” R ligand in the catalyst precursor, is proposed to control the reactivity of the complexes (see scheme).
Crystal‐clear structures : The first crystal structures of organometallic pincer–cutinase hybrids (see figure) provide insight into the 3D structural arrangement of both the protein and the organometallic pincer moiety, and reveal different binding modes for different pincers.
Going through the phases : The title reaction was found to proceed by an initial base‐mediated isomerization to allenyl esters and subsequent phase transfer catalyzed alkylation at the α position of the ester (see scheme).
Designing superacids: A computational study of protonated boratabenzenes and the gas‐phase acidity of their conjugate acids is presented. Conjugate acids of boratabenzenes substituted with CN or CF3 groups (see figure) are highly acidic species; the protonated hexacyanoboratabenzene and hexakis(trifluoromethyl)boratabenzene have computational gas‐phase acidities of 250.5 and 276.8 kcal mol?1, respectively.
Constructing α‐stereogenic amides and ketones : The highly regioselective and enantioselective conjugate addition of 1,3‐dicarbonyl compounds to 1,4‐dicarbonyl but‐2‐enes has been developed with the chiral bicyclic guanidine as catalyst (ee values up to 97 %; see scheme).
“Co”axing selectivity into isomerization : Treatment of 1‐alkenes with dimethylphenylsilylmethylmagnesium chloride in the presence of a cobalt‐NHC complex in dioxane at 50 °C or higher provides the corresponding (E)‐2‐alkenes selectively. The isomerization is applicable to the stereoselective synthesis of (E)‐crotylsilanes and (E)‐1‐propenylsilanes from the corresponding homoallylsilanes and allylsilanes, respectively.
High pressure under the spotlight : A new milliliter‐scale reactor is developed for using supercritical CO2 to perform continuous photo‐oxidation reactions. Changing from a traditional microliter‐scale batch reaction to 8 hours of reaction using the new reactor gives a 3000‐fold scale‐up of the oxidation of α‐terpinene (see picture).
Size matters! The structure and dynamics of the tetratolyl Group 14 elements, which were probed by using high‐resolution inelastic neutron scattering spectra, show a remarkable dependence on the size of the central atom. The para‐methyl groups at the periphery of the molecules constitute the frontier intermolecular interactions of increasingly larger tetrahedra, which becomes critical at the molecular radius of the Si and Ge analogues (see picture).
The first highly enantioselective allylic–allylic alkylation of α,α‐dicyanoalkenes and Morita–Baylis–Hillman carbonates by dual catalysis of (DHQD)2AQN and (S)‐BINOL has been investigated. Excellent stereoselectivities have been achieved for a broad spectrum of substrates (d.r. > 99:1, up to 99 % ee). The multifunctional allylic products could be efficiently converted to a range of complex chiral cyclic frameworks. EWG=electron‐withdrawing group, (DHQD)2AQN=hydroquinidine (anthraquinone‐1,4‐diyl) diether, (S)‐BINOL =(S)‐(?)‐1,1′‐bi‐2‐naphthol.
Brilliance of terbium : Heterodimeric conjugates of trimethoprim covalently linked to sensitized terbium chelates bind to Escherichia coli dihydrofolate reductase fusion proteins with nanomolar affinity (see picture). Terbium luminescence enables sensitive and time‐resolved detection of labeled proteins in vitro and on the surface of living mammalian cells.
Atomic oxygen adsorbed on metallic gold promotes the low‐temperature transformation of methanol to methyl formate, formaldehyde, and formic acid. The reactions occur with oxygen‐containing gold nanoparticles (ca. 2 nm in diameter), which form when Au(111) is oxidized with ozone. The detailed reaction mechanism is discussed by C. M. Friend and co‐workers in the Communication on page 4206 ff.
Leading light : A series of zinc(II) bis‐terpyridine complexes (see picture) is investigated by means of DFT calculations combined with Bader's quantum theory of atoms in molecules. Raman spectroscopy experiments and studies of the electro‐optical properties of the complexes in solution and the solid state are also performed to examine their potential as new emissive materials in light‐emitting devices.
Reaction rates from polarized spectroscopy : A new method based on ultrafast pump–probe polarization spectroscopy enables the measurement of the ground‐ and excited‐state reaction rates for self‐exchange processes. The technique was used to study double hydrogen transfer in porphycene and its derivatives (see figure).
