Proof‐of‐principle is reported for a directed functionalization and derivatization of chalcogenidometallate cages with respect to the formation of hybrid compounds containing (M)/T/E semi‐conductor nodes (M=Cu; T=Ge, Sn; E=S). In their Full Paper on page 6595 ff. , S. Dehnen et al. show how it is possible to generate functionalized ternary CuSnS or CuGeS clusters and to transfer COMe ligands into CR(N–NH2) or CR(N–NHPh) terminal groups by reaction of a series of novel, functionalized thiometallate cages [(RT)nSm] (n/m=4/6, 3/4), the R ligands of which are terminated by COO(H) or COMe.
The complex redox behavior of mixed lutetium/yttrium nitride clusterfullerenes of the series LuxY3?xN§C80(Ih, x=0–3) (see figure) results in up to three irreversible reduction steps. A reduction mechanism is proposed based on fast‐scan and square‐wave voltammetry experiments combined with simulations of the voltammograms.
Gal‐PUGNAc (see picture), a highly selective inhibitor for β‐hexosaminidases HEXA and HEXB is cell‐permeable and modulates the activity of HEXA and HEXB in tissue culture, increasing ganglioside GM2 levels. Gal‐PUGNAc should allow the role of these enzymes to be studied at the cellular level without generating a complex chemical phenotype from concomitant inhibition of O‐GlcNAcase.
Economical atoms : 2‐Cyclopenten‐1‐ones, 5‐alkylidenefuran‐2(5 H)‐ones and indan‐1‐ones have been synthesized by atom‐economic reductive cyclocarbonylation of internal alkynes with carbon monoxide catalyzed by [{RhCl(CO)2}2]/CO(NH2)2 in the presence of water (see scheme).
Chains of cages : Neutral/ionic [B12H12]2? boron‐cage‐functionalized methacrylate and styrene homopolymers or copolymers (see picture) are non‐crystalline solids, Tg increases as the number of B12 cages in the chain of polystyrene increases, and homopolymers retain more weight than the copolymers when heated to 400 °C.
Although free from structural disorder , the new intermetallic compound Cd13?xInySb10 (see figure) displays similarly low thermal conductivity values as disordered thermoelectric β‐Zn4Sb3 with an isostructural framework.
Work‐alcoholic! The elusive enantioselective catalytic α‐alkylation of aldehydes, a widely sought transformation, was brought to execution by the use of alcohols capable of forming stabilized carbocations (see scheme, TFA=trifluoroacetic acid).
Two dragons playing ball : Direct metal–metal bond formation using a π‐conjugated dinuclear metalladithiolene complex with two electron‐deficient metal centers as building blocks led to a cyclic double trinuclear heterometalladithiolene cluster with two parallel plane bridges (see structure; Rh pink, Mo green, S yellow, C gray, O red).
Pushing the limits of coordination chemistry : The most weakly coordinated silver complexes of the very weakly coordinating solvents dichloromethane and liquid sulfur dioxide were prepared. Special techniques at low temperatures and the use of weakly coordinating anions allowed structural characterization of [Ag(OSO)][Al{OC(CF3)3}4], [Ag(OSO)2/2][SbF6], and [Ag(Cl2CH2)2][SbF6] (see figure). An investigation of the bonding shows that these complexes are mainly stabilized by electrostatic monopole–dipole interactions.
NHC with EWGs for RCM : Ruthenium complexes with two N‐heterocyclic carbenes (NHCs), one of them substituted with electron‐withdrawing groups (EWGs), are highly efficient (pre)catalysts for the synthesis of tetrasubstituted olefins and trisubstituted olefins by ring‐closing metathesis reactions (RCM, see scheme).
A convenient route with high stereo control to γ‐acetoxy dienoates is provided by the reaction of methyl propiolate with aldehydes in the presence of ZnEt2 and N‐methylimidazole at room temperature, followed by the catalytic conversion of the resulting γ‐hydroxy‐α,β‐acetylenic esters with p‐N,N‐dimethylaminopyridine (DMAP) in acetic anhydride (see scheme).
The light fantastic : Two new 2‐(benzo[b]thiophene‐3‐yl)pyrroles have been synthesized, and are shown to exhibit optical properties that are promising for optoelectronic materials and devices such as highly efficient fluorescent sensors (see scheme). In addition a new BODIPY fluorophore, derived from 2‐(benzo[b]thiophene‐3‐yl)pyrrole, was also isolated and shows good spectroscopic properties in solution which are fully preserved in the solid state.
Josi or Mandy? Asymmetric conjugate addition of diboron to acyclic enones catalyzed by copper affords chiral organoboronates that possess a boronate group at the β stereocenter with excellent chemical yields and enantioselectivities (see scheme). This method accommodates the structural variation of acyclic enones and provides access to highly functionalized chiral organoboronates in one step.
Modeling magnetism: The antiferromagnetic ground state of the C60/Si(001)‐c(4×4) surface is predicted by means of density functional theory calculations. Two adjacent dangling bonds (DBs) generated by the adsorption of C60 are antiferromagnetically coupled with each other. This study demonstrates that magnetic Si surfaces can be prepared by engineering single Si DBs with unpaired electrons.
The carbodiimides 5 , obtained from reactions of iminophosphorane 4 with aromatic isocyanates, reacted with amines, phenols or ROH to give 2‐substituted 5,6,7,8‐tetrahydropyrido[4′,3′:4,5]thieno[2,3‐d]‐pyrimidin‐4(3H)‐one 7 in the presence of catalytic amount of sodium alkoxide or solid potassium carbonate in satisfactory yields. 相似文献
Get into the groove : The first high‐resolution structure of a foldamer bound to a protein target is described (see picture; foldamer in sticks). The foldamer consists of α‐ and β‐amino acid residues and is bound to the anti‐apoptotic protein Bcl‐xL. The overall binding mode and key interactions observed in the foldamer/Bcl‐xL complex mimic those seen in complexes of Bcl‐xL with natural α‐peptide ligands. Additional contacts in the foldamer/Bcl‐xL complex involving β‐amino acid residues appear to contribute to binding affinity.
