Multiwfn is a multifunctional program for wavefunction analysis. Its main functions are: (1) Calculating and visualizing real space function, such as electrostatic potential and electron localization function at point, in a line, in a plane or in a spatial scope. (2) Population analysis. (3) Bond order analysis. (4) Orbital composition analysis. (5) Plot density-of-states and spectrum. (6) Topology analysis for electron density. Some other useful utilities involved in quantum chemistry studies are also provided. The built-in graph module enables the results of wavefunction analysis to be plotted directly or exported to high-quality graphic file. The program interface is very user-friendly and suitable for both research and teaching purpose. The code of Multiwfn is substantially optimized and parallelized. Its efficiency is demonstrated to be significantly higher than related programs with the same functions. Five practical examples involving a wide variety of systems and analysis methods are given to illustrate the usefulness of Multiwfn. The program is free of charge and open-source. Its precompiled file and source codes are available from http://multiwfn.codeplex.com.

Multiwfn: a multifunctional wavefunction analyzer.

Self-Assembly of Discrete Cyclic Nanostructures Mediated by Transition Metals

The biaryl structural motif is a predominant feature in many pharmaceutically relevant and biologically active compounds. As a result, for over a century 1 organic chemists have sought to develop new and more efficient aryl -aryl bond-forming methods. Although there exist a variety of routes for the construction of aryl -aryl bonds, arguably the most common method is through the use of transition-metalmediated reactions. 2-4 While earlier reports focused on the use of stoichiometric quantities of a transition metal to carry out the desired transformation, modern methods of transitionmetal-catalyzed aryl -aryl coupling have focused on the development of high-yielding reactions achieved with excellent selectivity and high functional group tolerance under mild reaction conditions. Typically, these reactions involve either the coupling of an aryl halide or pseudohalide with an organometallic reagent (Scheme 1), or the homocoupling of two aryl halides or two organometallic reagents. Although a number of improvements have developed the former process into an industrially very useful and attractive method for the construction of aryl -aryl bonds, the need still exists for more efficient routes whereby the same outcome is accomplished, but with reduced waste and in fewer steps. In particular, the obligation to use coupling partners that are both activated is wasteful since it necessitates the installation and then subsequent disposal of stoichiometric activating agents. Furthermore, preparation of preactivated aryl substrates often requires several steps, which in itself can be a time-consuming and economically inefficient process.

http://aether.cmi.ua.ac.be/artikels/Artikels%20Gitte/Artikels/Reviews/Heck-Type-lautens.pdf

Aryl-aryl bond formation by transition-metal-catalyzed direct arylation.

THE definitions currently used to classify chemical bonds (in terms of bond order, covalency versus ionicity and so forth) are derived from approximate theories1–3 and are often imprecise. Here we outline a first step towards a more rigorous means of classification based on topological analysis of local quantum-mechanical functions related to the Pauli exclusion principle. The local maxima of these functions define 'localization attractors', of which there are only three basic types: bonding, non-bonding and core. Bonding attractors lie between the core attractors (which themselves surround the atomic nuclei) and characterize the shared-electron interactions. The number of bond attractors is related to the bond multiplicity. The spatial organization of localization attractors provides a basis for a well-defined classification of bonds, allowing an absolute characterization of covalency versus ionicity to be obtained from observable properties such as electron densities.

Classification of chemical bonds based on topological analysis of electron localization functions

The development in the field of coordination polymers or metal-organic coordination networks, MOCNs (metal-organic frameworks, MOFs) is assessed in terms of property investigations in the areas of catalysis, chirality, conductivity, luminescence, magnetism, spin-transition (spin-crossover), non-linear optics (NLO) and porosity or zeolitic behavior upon which potential applications could be based.

/pdf/engineering-coordination-polymers-towards-applications-3joywh2v74.pdf

Engineering coordination polymers towards applications

The Diastereoselective Synthesis of Ester-Functionalized Alkenes through the Stereocontrolled Conjugate Addition (Michael Reaction) of Prochiral Enolates to Chiral .alpha.-Methylene .beta.-Lactones and Thermal Decarboxylation of the Resulting .alpha.-Substituted .beta.-Lactones

Askani's synthesis of the 1,5-dialkylsemibullvalenes 1a and c was optimised on a gram scale. The as yet unknown trimethylenesemibullvalene 1b was obtained according to the same protocol which also greatly improved a recent synthesis of barbaralane (2). Allylic brominations of the dienes 5 + 6 with N-bromosuccinimide yielded complex mixtures of 7–10. Depending on the substitution pattern at the apical carbon atoms C-1 and C-5 of the bicyclo[3.3.0]octadiene system, the intermediate allylic radicals are attacked preferentially either from the exo (R = Me) or from the endo face [R, R = (CH2)3, (CH2)4]. Reductive cyclisations of the dibromides 9 and exo,exo-15 were carried out with a sonicated suspension of an activated zinc-copper couple in tetraglyme. Sweeping of the volatile products from the reaction mixtures with nitrogen at elevated temperatures allowed the convenient isolation of the semibullvalenes 1 and barbaralane (2) in reasonable purities (92–97%) and yields (57–82%).

Optimised preparation of 1,5‐dialkylsemibullvalenes

[InAs3]6⊖ und [AlSb3]6⊖, trigonal-planare Anionen in Cs6InAs3 und Cs6AlSb3†

Die Mannich-Reaktion von cis-3,5-Diphenylcyclohexanon (3a) ergab mit Ammoniumacetat und Benzaldehyd die diastereomeren Tetraphenyl-3-azabicyclo[3.3.1]nonanone 4a(A) = 14a und 4a(B) = 2a, mit Ammoniumacetat und 4-Chlorbenzaldehyd dagegen das sterisch einheitliche 4b = 14b. Wolff-Kishner-Reduktion der Ketone lieferte die 3-Azabicyclononane 7a(A), 7a(B) bzw. 7b. 4a(B) und 7a(B) wurden mit Methyliodid zu 5a(B) bzw. 8a(B) methyliert. Die Konfiguration und die im Kristall und in Losung vorliegende Konformation der Tetraaryl-3-azabicyclo[3.3.1]-nonane wurden durch Rontgenstrukturanalyse von 4b sowie durch IR-, 1H-NMR- und 13C-NMR-Spektroskopie aufgeklart: Danach stehen in beiden Konfigurationen A und B alle Arylgruppen aquatorial an den Sechsringen mit Sessel- oder Boot-Konformation.



In den 3-Azabicyclononanen mit der Konfiguration A[4a(A), 7a(A), 4b, 6b, 7b] liegt der Piperidinring in der Sessel-, der Cyclohexanring in der Boot-Konformation vor. Bei 4a(B)–8a(B) sind die Konformationen der Sechsringe vertauscht. Die Dichotomie des sterischen Verlaufs der Mannich-Reaktion der cis-Diphenylsechsringketone 3a–d wird diskutiert.



Synthesis and Structure of Diastereomeric 2,4,6,8-Tetraaryl-3-azabicyclo[3.3.1]nonanes and their Conformation in the Crystal and in Solution. Stereochemistry of the Mannich Reaction of cis-3,5-Diphenylcyclohexanone and -4-heteracyclohexanones



In the Mannich reaction with ammonium acetate and benzaldehyde, cis-3,5-diphenylcyclohexanone (3a) afforded a mixture of the diastereomeric tetraphenyl-3-azabicyclo[3.3.1]nonanones 4a(A) = 14a and 4a(B) = 2a. In contrast, the use of 4-chlorobenzaldehyde instead of benzaldehyde gave rise to the sterically uniform 4b = 14b. Wolff-Kishner reduction of the ketones produced the 3-azabicyclononanes 7a(A), 7a(B), and 7b, respectively. 4a(B) and 7a(B) were methylated using methyl iodide to afford 5a(B) and 8a(B), respectively. The configuration of the tetraaryl-3-azabicyclo[3.3.1]nonanes and their conformation in the solid state and in solution have been determined by X-ray structure analysis of 4b as well as by IR, 1H NMR, and 13C NMR spectroscopy. Consequently, all aryl groups are arranged equatorial to the six-membered rings of boat as well as of chair conformation in both configurations A and B. The 3-azabicyclononanes of the configuration A [4a(A), 7a(A), 4b, 6b, 7b] present a piperidine ring with a chair conformation and a cyclohexane ring with a boat conformation. In 4a(B)–8a(B) the conformations of the six-membered rings have been exchanged. The dichotomy in the steric course of the Mannich reaction of the cis-diphenyl six-membered ring ketones 3a–d is discussed.

Synthese und Struktur diastereomerer 2,4,6,8‐Tetraaryl‐3‐azabicyclo[3.3.1]nonane und ihre Konformation im Kristall und in Lösung. Stereochemie der Mannich‐Reaktion von cis‐3,5‐Diphenylcyclohexanon und ‐4‐heteracyclohexanonen

Nach Umsetzung von 1,2-Cyclopentandion (1c, 9) mit dem 3-Oxoglutarsaureester 4 in Methanol/Wasser in Gegenwart von Natriumhydrogencarbonat, saurer Hydrolyse und Decarboxylierung des Produktgemischs erhalt man neben dem [3.3.3]Propellandion 6c den Oxa[3.3.3]propellanester 11c. Die Alkali-Enolate von 4 reagieren mit 9 in siedendem Methanol zu den gelben, schwer loslichen Dihydropentalenolaten 12M und dem [3.3.3]Propellantetraester 5c, der nach Hydrolyse und Decarboxylierung 53% 6c ergibt. Das Dihydropentalenol 12H liegt im Gleichgewicht mit dem tautomeren β-Oxodiester 13 vor, dessen Anteil mit der Polaritat des Losungsmittels zunimmt. In Methanol addieren sich 12H und 13 diastereoselektiv und bilden den Dicyclopenta-s-indacentetraester syn-14, der sich von einem neuartigen, pentacyclischen Ringsystem ableitet. Die Konfiguration von syn-14 wird durch Rontgenstrukturbestimmung aufgeklart. Die Mechanismen der Bildung von 11c, 12M und syn-14 werden diskutiert.



Novel Products in the Weiss Reaction of 1,2-Cyclopentanedione. Improved Preparation of [3.3.3]Propellane-3,7-dione



The reaction of 1,2-cyclopentanedione (1c, 9) with the 3-oxoglutarate 4 in methanol/water in the presence of sodium bicarbonate followed by hydrolysis and decarboxylation of the product mixture affords the oxa[3.3.3]propellane ester 11c in addition to the [3.3.3]propellanedione 6c. The alkali enolates of 4 react with 9 in boiling methanol to yield the yellow, poorly soluble alkali dihydropentalenolates 12M and the [3.3.3]propellane tetraester 5c, which on hydrolysis and decarboxylation yields 53% of 6c. The dihydropentalenol 12H equilibrates with the tautomeric β-oxodiester 13, the proportion of which increases with solvent polarity. In methanol solutions, 12H and 13 add diastereoselectively forming the dicyclopenta-s-indacene tetraester syn-14, which is derived from a novel pentacyclic ring system. The configuration of syn-14 is determined by X-ray diffraction analysis. The mechanisms of formation are discussed for 11c, 12M, and syn-14.

Hans Georg von Schnering

Papers

The Diastereoselective Synthesis of Ester-Functionalized Alkenes through the Stereocontrolled Conjugate Addition (Michael Reaction) of Prochiral Enolates to Chiral .alpha.-Methylene .beta.-Lactones and Thermal Decarboxylation of the Resulting .alpha.-Substituted .beta.-Lactones

Optimised preparation of 1,5‐dialkylsemibullvalenes

[InAs3]6⊖ und [AlSb3]6⊖, trigonal-planare Anionen in Cs6InAs3 und Cs6AlSb3†

Synthese und Struktur diastereomerer 2,4,6,8‐Tetraaryl‐3‐azabicyclo[3.3.1]nonane und ihre Konformation im Kristall und in Lösung. Stereochemie der Mannich‐Reaktion von cis‐3,5‐Diphenylcyclohexanon und ‐4‐heteracyclohexanonen

Neuartige Produkte der Weiss-Reaktion von 1,2-Cyclopentandion Verbesserte Herstellung von [3.3.3]Propellan-3,7-dion