A new solid-state chemistry based on a kinetic approach instead of the usual thermodynamic concepts should provide access to new sophisticated and organized materials. This has already been illustrated by the synthesis of nanocomposite ceramics, organic – inorganic hybrid materials, and nanostructures. A monocomponent hybrid material containing a building block (represented by the rectangle in the scheme) can be treated with a catalyst (H⁺, OH⁻, F⁻) and H₂O to provide a nanostructure in which the organic unit is covalently bound to the matrix and thus nonseparable. R=OMe, OEt, OiPr.

Biological clocks are an important theme for science in the 21st century. In contrast to animals, the biological clock in plants is far from being understood, although it was originally discovered from observation of the leaf movement of Mimosa pudica L in the 18th century. This review focuses on the so-called leaf-movement factors, chemical substances which control the movement of plant leaves, and their regulation by the biological clock (represented schematically). Mimosa plants are also well known for rapid movement of their leaves and the chemical substances inducing this rapid movement are also included in this review.

A formidable challenge for today's synthetic chemists was presented by the total syntheses of the title compounds 1 and 2. The research groups of Nicolaou and Danishefsky have answered the challenge and completed the total syntheses; many more research groups have made great progress in tackling these structures and have enriched synthetic organic chemistry with their innovative strategies.

Conventional wisdom in the instability of pure carbonic acid has been proven false. Chemists recently succeeded in isolating and spectroscopically characterizing the compound (see picture). Shortly after, Liedl and co-workers explained why carbonic acid exists in its free state and why it decomposes so quickly in aqueous solution.

Remarkable parallels to Hittorf's phosphorus are exhibited by the P₁₁ ligand (unknown in the free form) of the trinuclear iron complex (see structure), which forms as a by-product in the thermolysis of the title compound (Cp^R=iPr₅C₅) in the presence of PhC≡CPh. However, the main product of the reaction is, as in the case of Cp^R=C₅H₂tBu₃, the sandwich complex [Cp^RFe(η⁵-P₃C₂Ph₂)] with a 1,2,3-triphospholyl ligand.

Hydroformylation as well as hydrogenation are efficiently catalyzed by Rh complexes formed from chiral QUINAPHOS ligands (see picture), which are readily synthesized and are available in both enantiomeric forms. For example, (R_a,R_c)-nBu-QUINAPHOS (Ar=Ph, O−O=(R_a)-binaphthol, R=nBu) is among the most selective ligands known to date for the first reaction, and the (R_a,S_c) diastereomer forms extremely active (turnover frequency≥36 000 h⁻¹) and highly selective (>99 % ee) Rh catalysts for the second reaction.

Stereoselectively on solid phase: the Ugi four-component reaction, which because of its high potential for the generation of molecular diversity is particularly important in combinatorial synthesis, has been accomplished in this way for the first time by using a polymer-linked galactosylamine (1) bound through a suitable anchor and spacer. Piv=pivaloyl=tBuCO.

Fast and efficient chromatographic separations are made possible with a new class of continuous separation media that are synthesized by ring-opening methathesis polymerization (ROMP) and which in a second step—again through ROMP—undergo tailored functionalization (see scheme).

A new NLO standard has been set by compound 1 for the substance class of analines: Their second-order polarizability β is two orders of magnitude higher than that of the one-dimensional NLO prototype p-nitroaniline. This is an example of the optimization of nonlinear optical chromophores with a threefold axis of symmetry, a current challenge for synthetic organic chemistry.

The sphingolipid ceramide has been discusssed for some time as a possible secondary messenger for a number of physiological and pathalogical processes, including autoimmune diseases of the central nervous system, such as multiple sclerosis. Ceramide can be activated through the action of acid or neutral sphingomyelinases. The spiroepoxide 1 is the first selective irreversible inhibitor of neutral sphingomyelinase and will, therefore, be useful in the elucidation of the biological function of ceramide.

Pu^IV complexed by desferrioxamine E (DFE) is nine coordinate with a tricapped trigonal prismatic geometry. The DFE ligand lies in one hemisphere and three water molecules occupy the other (see structure). These and other features of the Fe^III and Pu^IV structures provide insights into the ferrioxamine-like mechanisms used by microorganisms for transporting metals across membranes.

A minimal lifetime of microseconds is displayed by the dication GeH²⁺, which has been detected for the first time as the product of charge-stripping experiments at 8 kV involving [GeH₂]⁺ and O₂. Coupled-cluster calculations suggest that XH²⁺ (X=Si, Ge) are both metastable with respect to internal conversion and dissociation via X⁺ and H⁺. The picture shows a potential energy surface scan of GeH²⁺ (—) and the corresponding Coulomb repulsion asymptote (- - - -).

The T-shaped molecular structure of unstable IF₃ has been characterized for the first time by X-ray analysis. In the solid state the iodine atom is pentagonal-planar coordinated (see picture), as a result of two weak bonds bridging through fluorine atoms of neighboring molecules (d=276.9(3) pm).

Endothelial NO synthase (eNOS) is a membrane-bound protein involved in signaling from the blood stream to the surrounding smooth muscle cells. The synthesis of its N-myristolyated and doubly S-palmitoylated N-terminus 1, which determines the localization of this protein in the plasma membrane and caveolae of endothelial cells, is achieved by a combination of enzyme-, acid-, and noble-metal-sensitive protecting groups with solid-phase methods and fragment-condensation techniques.

A novel peroxide substrate with a benzooxadiazole backbone: 4-(N-methylhydrazino)-7-nitro-2,1,3-benzooxadiazole (MNBDH; 1) is introduced as a prototype for a new class of fluorogenic peroxide substrates. The advantages of 1 lie in its lower detection and quantification limits, a favorable red-shifted fluorescence signal, and a greater signal stability after the successful reaction. The new substrate was validated by the determination of α-D-glucose in beverages.

One needs their neighbors—especially when four nonbinding electon pairs are fixed elliptically on the same molecular side! In the cation 2 (see picture) and the violet radical cation, generated by protonation and by single-electron oxidation, respectively, of the all cis-corsetted tetrazalodine 1, σ-delocalization exists between the N atoms of the tetrazane chain with bond lengths greater than 2 Å.

Monodisperse, rodlike molecules 1 composed of repeating individual chromophores that have substantial electronic interactions in the ground state have been synthesized by the meso – meso coupling of porphyrins. The 128-mer (n=63) at about 106 nm long is the longest such system known. The S₁ states are delocalized over 6 – 8 porphyrin units. Ar=3,5-dioctyloxyphenyl.

Grignard chemistry?—That is all known for more than 100 years! Thus, it is truely unexpected when a new Grignard reaction comes to light: a carbenoid C−H insertion into the α-C−H bond of a Grignard reagent [Eq. (1)].

Built up from acetate, dioncophylline A is the only acetogenic tetrahydroisoquinoline alkaloid as yet known (see scheme). This new biosynthetic pathway was proved by feeding experiments with [¹³C₂]acetate.

Truly diverse aggregation and coordination abilities are observed for the chiral lithium amides 1 and 2! Symmetrically and unsymmetrically solvated dimers as well as cyclic trimers (see picture) are formed depending on the solvent and the stereochemical composition of the aggregate.

New blue/violet laser diodes and LEDs need InN-containing alloys to provide the light-emitting constituents, but InN typically requires crystal growth temperatures (427 – 550 °C) commensurate with its decomposition. A new method allows InN synthesis as a fiber (see picture) at only 203 °C. This method suggests new approaches to produce thermally unstable materials.

Reversible hypercloso – closo interconversion by means of simple redox chemistry: Two-electron reduction of hypercloso-[1-(η⁶-C₆Me₆)-1-RuB₉H₉] (1) gives the closo dianion 2²⁻, which displays the bicapped square-antiprismatic structure expected for a closo cluster with 2n+2 skeletal electrons. The dianion 2²⁻ is quantitatively oxidized back to 1 by simple air oxidation.

A straightforward way to determine enantiomeric ratios and predict absolute configurations in organozinc reagents is possible by the use of (+)-2,2′-isopropylidene-bis((R)-4-phenyloxazoline) ((+)-1) and its racemic counterpart (±)-1 as chiral solvating agents for NMR spectroscopy. The signals corresponding to the α-hydrogen atom (relative to the zinc atom) in a secondary organozinc bromide and its evolution after chiral (left) and racemic (right) complexation are shown.

A structural model of the O₂-evolving center in photosystem II is provided by complex 1. The two ruthenium – hydroxo units in the complex play a key role in the oxidation of water to O₂. Deposition of the complex on an indium – tin-oxide electrode has enabled 15.0 mL of O₂ (turnover 6730) to be evolved from the controlled-potential electrolysis of water at +1.7 V.

Units with large effective dipole moments (shown schematically) are suggested to explain the observation of spontaneous piezoelectric behavior in polar self-assembled films comprised of clusters formed by rod-coil molecules. The piezoelectric response of heated films remains upon cooling.

Molecular order and mobility suggest a new strategy to engineer nanostructures. Helical metallomesogens, formed from nonmesomorphic, segmented, iminoterpyridine ligands coordinated to copper(I) centers, align into rows within sublayers of an ordered biaxial smectic phase (see picture) without third-dimensional correlation of the layers. Selective oxidation of a dicopper helicate to a mixed Cu^I/Cu^II mesogen occurs under ambient conditions.

New insight into the biogenetic origin of stenusine 1, the spreading agent of the beetle Stenus comma, is gained from the results of a one-pot synthesis of the natural and the racemic compound [Eq. (1)]. On the basis of these results a plausible biogenetic pathway to 1 is proposed.

The cyclic hexamer obtained by the condensation of furan and acetone can be used as a convenient starting material for the syntheses of calix[6]pyrrole 1 and of several “hybrid systems” containing both furan and pyrrole units. The solid-state structure of 1 shows a water molecule held inside the cavity by six hydrogen-bonding interactions, while that of the “alternating” calix[3]furan[3]pyrrole 2 contains no water molecules, despite the macrocycles having a similar structure.

Thinly sliced zeolites have greater catalytic activity! A common precursor gives ferrierite or, upon expansion and delamination, ITQ-6 (see picture). Delamination increases the external surface area and catalytic reactions with bulky molecules do not demand their permeation into the Angstrom-scale pores. The preparation also eases creation of even more active, titanium-enriched materials.

Sn^II/Sn^IV double-cubanes [Sn₇(NR)₈], and not as expected simple imidotin(II) cubanes of the type [{SnNR}₄], are obtained from reactions of [Sn(NMe₂)₂] with 2-aminopyridines and -pyrimidines (the structure of the 2-imidopyrimidine derivative is shown). This ligand-dependent structural modification may indicate an as yet untapped area of electrochemistry involving other main group metal cage complexes.

Monolithic Ti-TADDOLate catalysts (see picture) prepared by polymerization or grafting show a long-term stability (several months). The polymeric backbone can play a central role in determining the stereochemical outcome of the Diels – Alder reaction between cyclopentadiene and 3-crotonoyl-1,3-oxazolin-2-one.

The peculiar spongelike behavior of the nanoporous crystal, composed from the self-assembly of copper(II) sulfate and 1,3-bis(4-pyridyl)propane, is derived from its unusual topology: an architecture comprising two different structural motifs. The supramolecular catenation (see the picture) features ribbons-of-rings interpenetrating and entangling (4,4) layers.

Morphologically chiral crystals of sodium chlorate induce highly enantioselective synthesis. Thus the addition of diisopropylzinc to 2-(tert-butylethynyl)pyrimidine-5-carbaldehyde in the presence of d- and l-NaClO₃ gives the (S)- and (R)-alkanol, respectively, in high yields and with high ee values (see scheme).