Synthesis of Bis(phosphinoyl)amines and Phosphinoyl–Phosphorylamines by the N‐Phosphinoylation and N‐Phosphorylation of 1‐Alkylamino‐2,5‐dihydro‐1H‐phosphole 1‐Oxides

The N‐phosphinoylation and N‐phosphorylation reaction of 1‐alkylamino‐2,5‐dihydro‐1H‐phosphole 1‐oxides with diphenylphosphinoyl chloride and diethylphosphoryl chloride/diphenylphosphoryl chloride afforded new families of compounds comprising bis(phosphinoyl)amines and phosphinoyl‐phosphorylamines, respectively, whose stereostructures were elucidated by B3LYP/6‐31G(d,p) and B3LYP/6‐31G++(d,p) calculations. The P analogues of the mixed imides may be valuable intermediates in syntheses.     

Molecular Chirality in Meteorites and Interstellar Ices,and the Chirality Experiment on Board the ESA Cometary Rosetta Mission

Life, as it is known to us, uses exclusively L ‐amino acid and D ‐sugar enantiomers for the molecular architecture of proteins and nucleic acids. This Minireview explores current models of the original symmetry‐breaking influence that led to the exogenic delivery to Earth of prebiotic molecules with a slight enantiomeric excess. We provide a short overview of enantiomeric enhancements detected in bodies of extraterrestrial origin, such as meteorites, and interstellar ices simulated in the laboratory. Data are interpreted from different points of view, namely, photochirogenesis, parity violation in the weak nuclear interaction, and enantioenrichment through phase transitions. Photochemically induced enantiomeric imbalances are discussed more specifically in the topical context of the “chirality module” on board the cometary Rosetta spacecraft of the ESA. This device will perform the first enantioselective in situ analyses of samples taken from a cometary nucleus.     

Network Formation in PP/Layered Silicate Nanocomposites: Modeling and Analysis of Rheological Properties

PP/organophilic montmorillonite composites were prepared from PP homopolymer, maleinated polypropylene and a clay organophilized with octadecyl amine. Various approaches were used to analyze the rheological properties of the composites. Cole-Cole plots proved to be useful, since they detect the network very sensitively. The frequency dependence of the real part of complex viscosity was described with a series of Maxwel bodies coupled parallel to each other. The relaxation time of the melt changed in the range of 0.0005 and 200 sec. Under certain conditions long relaxation times appear in the spectrum, which indicate the formation of new structural units, probably a silicate network. A certain number of silicate layers are needed to create a house-of-cards structure. A threshold concentration of MAPP exists for network formation, which depends on silicate content.     

Reactions of substituted furan-2-carboxaldehydes and furo[b]pyrrole type aldehydes with benzothiazolium salts

A series of new push-pull compounds were synthesised by reaction of 5-aryl- furan-2-carboxaldehydes and furo[b]pyrrole type aldehydes with benzothiazolium salts. These new condensation products represent highly conjugated systems that have potential biological activity. The reaction of furo[b]pyrrole type aldehydes with benzothiazolium salts give potential precursors of cyanine dyes.     

Vapor phase tin diiodide: its structure and thermodynamics,a computational study

The molecular structure and vibrational characteristics of monomeric and dimeric tin diiodide, SnI₂ and Sn₂I₄, were determined by high-level computational methods. For the dimer molecule two low-energy geometries were found, one with C _s and the other with C _2v symmetry, the former with somewhat lower energy; their relative energy is strongly dependent on the computational method. Thermodynamic functions for both species and their dimerization reaction were calculated based on the computed structures.

Enantioselective Cyclopropanation Catalyzed by Gold(I)-Carbene Complexes

The formation of polysubstituted cyclopropane derivatives in the gold(I)-catalyzed reaction of olefins and propargylic esters is a potentially useful transformation to generate diversity, therefore any method in which its stereoselectivity could be controlled is of significant interest. We prepared and tested a series of chiral gold(I)-carbene complexes as a catalyst in this transformation. With a systematic optimization of the reaction conditions, we were able to achieve high enantioselectivity in the test reaction while the cis:trans selectivity of the transformation was independent of the catalyst. Using the optimized conditions, we reacted a series of various olefins and acetylene derivatives to find that, although the reactions proceeded smoothly and the products were usually isolated in good yield and with good to exclusive cis selectivity, the observed enantioselectivity varied greatly and was sometimes moderate at best. We were unable to establish any structure-property relationship, which suggests that for any given reagent combination, one has to identify individually the best catalyst.     

Electrospray ionization mass spectrometric analysis of highly reactive glycosyl halides

Highly reactive glycosyl chlorides and bromides have been analysed by a routine mass spectrometric method using electrospray ionization and lithium salt adduct-forming agents in anhydrous acetonitrile solution, providing salient lithiated molecular ions [M+Li]?, [2M+Li]? etc. The role of other adduct-forming salts has also been evaluated. The lithium salt method is useful for accurate mass determination of these highly sensitive compounds.     

Synthesis of α‐aminophosphonates from α‐hydroxyphosphonates; a theoretical study

Two types of reactions, namely the Pudovik reaction of benzaldehyde and acetophenone with diethyl phosphite as well as the substitution of the α‐hydroxyphosphonates so‐formed by primary amines to afford α‐aminophosphonates, were evaluated by quantum chemical calculations at the B3LYP/6‐31G(d,p) level. An unexpected neighboring group effect was found to enhance the substitution. A series of new α‐aminophosphonates was synthesized by the microwave‐assisted substitution of α‐hydroxyphosphonates by alkylamines.