Olive‐Shaped Chiral Supramolecules: Simultaneous Self‐Assembly of Heptameric Lanthanum Clusters and Carbon Dioxide Fixation

Cluster's last stand : Six chiral reduced Schiff base ligands containing amino acids and seven La^III ions self‐assemble to form a novel heptameric lanthanum supramolecule with the aid of the CO₃^2? ion (see picture). The cluster exists as a single chiral triple helix. The CO₃^2? ion, which is derived from atmospheric CO₂ , adopts a rare μ₃‐tridentate bridging mode that links three La^III ions, thus allowing the cluster to efficiently fix CO₂.

     

Solvent‐Slaved Protein Motions Accompany Proton but Not Hydride Tunneling in Light‐Activated Protochlorophyllide Oxidoreductase

H ⁺ but not H ^? : The reduction reaction of protochlorophyllide catalyzed by protochlorophyllide oxidoreductase features solvent‐slaved motions that control the proton‐ but not the hydride‐tunneling mechanism. These motions imply a long‐range dynamic network from the solvent to the enzyme active site that facilitate proton transfer (see picture, left). Motions for hydride transfer are more localized and are not slaved by the solvent (see picture, right).

     

High‐Yielding Synthesis of the Anti‐Influenza Neuramidase Inhibitor (−)‐Oseltamivir by Three “One‐Pot” Operations

Taking shortcuts : A remarkably short and high‐yielding asymmetric total synthesis of (?)‐oseltamivir takes advantage of organocatalysis and single‐pot domino operations. The target, known as the drug Tamiflu, is prepared efficiently in a short time, and also its derivatives can be synthesized effectively.

     

Water Splitting by Light with Osmocene as Photocatalyst

Last but not least : A simple molecular redox system is used to split water into hydrogen and oxygen photochemically. Two separate photolyses are combined to a cyclic process (see scheme). Osmocene ([Cp₂Os^II] with Cp^?=C₅H₅^?) serves as photocatalyst.

     

Facile Synthesis and Systematic Investigations of a Series of Novel Bent‐Shaped Two‐Photon Absorption Chromophores Based on Pyrimidine

Mark us bent! The synthesis, structure, and single‐ and two‐photon spectroscopic properties of a series of pyrimidine‐based (bent‐shaped) molecules are reported. These allow structure‐property relationships and guidelines for both the development and application of TPA compounds to be derived.

     

Room‐Temperature C?H Bond Activation of Methane by Bare [P4O10].+

No need for a metal : A combination of mass spectrometry and computational studies (density functional theory and coupled‐cluster methods) shows that [P₄O₁₀]^.+ is the first polynuclear nonmetal oxide cation that is capable of activating the C? H bond of methane at room temperature (see picture). This process represents a further example in the reactivity of oxygen‐centered radicals.

     

Phosphinoborane and Sulfidoborohydride as Chelating Ligands in Polyhydride Ruthenium Complexes: Agostic σ‐Borane versus Dihydroborate Coordination

A question of coordination mode : Two new borane compounds are prepared. They act as bifunctional ligands as illustrated by their reaction with ruthenium polyhydrides which leads to the formation of two complexes (see scheme) displaying either a δ‐agostic interaction of a η²‐B? H bond involving a trivalent boron atom or a dihydroborate ligation.

     

Synthetic Study of (−)‐Norzoanthamine: Construction of the ABC Ring Moiety

Throw your hat in the ring : A highly diastereoselective synthesis of the ABC rings of (?)‐norzoanthamine has been achieved starting from the (?)‐Hajos–Parrish ketone (see scheme). Three asymmetric quaternary carbon centers on the C ring were constructed by a 1,4‐addition, and an intramolecular Diels–Alder reaction provided a trans‐decalin scaffold on the AB rings.

     

Inside Cover: A Phosphine‐Mediated Conversion of Azides into Diazo Compounds (Angew. Chem. Int. Ed. 13/2009)

In 1919 H. Staudinger and J. Meyer reported the reductive fragmentation of an azide to an amine. In their Communication on page 2359 ff., E. L. Myers and R. T. Raines report the complementary reaction—cleavage of the other N? N bond in an azide to yield a diazo compound. Both transformations rely on a reagent that contains P^III. The painting, The Alchymist, in Search of the Philosopher's Stone, Discovers Phosphorus, by J. Wright (1771), depicts the discovery of phosphorus by H. Brandt in 1669 (cover art by H. A. Steinberg).

     

Yoshiaki Nishibayashi

“My first experiment was the Wittig reaction to prepare chiral allenes. If I wasn′t a scientist, I would be a historian. …?” This and more about Yoshiaki Nishibayashi can be found on page 4276.

     

Total Synthesis of (−)‐ and (+)‐Decarbamoyloxysaxitoxin and (+)‐Saxitoxin

Playing the sax : The enantioselective total syntheses of (?)‐ and (+)‐decarbamoyloxysaxitoxin (doSTX) and (+)‐saxitoxin (STX) are reported. A new methodology was developed for the synthesis of STXs, featuring discriminative reduction of the nitro group and N? O bond in nitroisoxazolidine.

     

Cover Picture: A Spin‐Crossover Cluster of Iron(II) Exhibiting a Mixed‐Spin Structure and Synergy between Spin Transition and Magnetic Interaction (Angew. Chem. Int. Ed. 8/2009)

A spin‐crossover cluster with the {Fe^II₄O₄} core structure is presented by D. Y. Wu, O. Sato et al. in their Communication on page 1475 ff. The cluster is synthesized by self‐assembly and shows an abrupt spin transition, giving two high‐spin and two low‐spin states. It exhibits complete light‐induced excited spin‐state trapping effects. Importantly, synergy effects between the magnetic interaction and spin transition operate in the cluster.

     

Gold Nanorod/Fe3O4 Nanoparticle “Nano‐Pearl‐Necklaces” for Simultaneous Targeting,Dual‐Mode Imaging,and Photothermal Ablation of Cancer Cells

Perlen auf Gold : Neuartige multifunktionelle Nanopartikel bestehen aus einzelnen Amin‐modifizierten Goldnanostäbchen, an denen Fe₃O₄‐„Perlen“ mit Carboxyendgruppe angebracht sind. Die Partikel eignen sich zur simultanen Erkennung, dualen Bildgebung und photothermischen Ablation von Brustkrebszellen.

     

Single and Double C?Cl‐Activation of Methylene Chloride by P,N‐ligand Coordinated Rhodium Complexes

Two in one : The simultaneous formation of bimetallic μ‐methylene bridged Rh^III complexes as well as dimeric Rh^III complexes with terminal chloromethyl groups is observed for P,N‐ligand stabilized Rh^I complexes by C? Cl bond activation of methylene chloride. A mechanistic proposal for the formation of both activation products is also discussed.