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Based on the DFT‐level calculated molecular volume (V mol ) of pyrrole and its liquid density, pyrrole manifests the highest liquid density coefficient LD c (defined as [V mol • density • 0.6023]/FW) value of 0.7. Normal liquids have LD c < 0.63. This very high LD c is due to the strong N‐H … π interactions in solution and hence pyrrole can be considered to be a pseudo‐crystalline liquid. When trapped inside the confined space of the crystalline sponge a reorientation of the N‐H … π interaction is observed leading to specific cyclic N‐H … π tetramers and N‐H … π dimers, verified by single crystal X‐ray crystallographic and computational methods. These tetramers are of the same size as four pyrrole molecules in the solid‐state of pyrrole, yet the cyclic N‐H … π intermolecular interactions are circularly oriented instead of the linear zig‐zag structure found in the X‐ray structure of a solid pyrrole. The confinement thus acts as an external driving force for the tetramer formation. peerReviewed

Sulfuric acid and dimethylamine vapours in the atmosphere can form molecular clusters, which participate in new particle formation events. In this work, we have produced, measured, and identified clusters of sulfuric acid and dimethylamine using an electrospray ionizer coupled with a planar-differential mobility analyser, connected to an atmospheric pressure interface time-of-flight mass spectrometer (ESI–DMA–APi-TOF MS). This set-up is suitable for evaluating the extent of fragmentation of the charged clusters inside the instrument. We evaluated the fragmentation of 11 negatively charged clusters both experimentally and using a statistical model based on quantum chemical data. The results allowed us to quantify the fragmentation of the studied clusters and to reconstruct the mass spectrum by removing the artifacts due to the fragmentation.

Iodonium complexes incorporating tertiary amines have been synthesised to study and explore why such species comprised of alkyl amines are relatively rare. The complexes were characterised in solution (1H and 15N NMR spectroscopy) and the solid state (SCXRD), and analysed computationally. peerReviewed

One-pot synthesis of three enaminones, (E)-1-(4-chlorophenyl)-3-morpholinoprop-2-en-1-one 1, (E)-1-(4-chlorophenyl)-3-(4-methylpiperazin-1-yl)prop-2-en-1-one 2, and (E)-1-(4-chlorophenyl)-3-(pyrrolidin-1-yl)prop-2-en-1-one 3 were achieved. The synthetic protocol via three components reaction of p-chloroacetophenone with DMFDMA (N,N-dimethylformamid-dimethylacetal) and the corresponding secondary amines (morpholine/N-methylpiperazine/pyrrolidine) in dioxane under heating for 2.5–4 h at 102 °C yielded the requisite enaminones. This protocol has the advantage of no separation of intermediate, no need for column purification with quantitative yield for the target compounds. The chemical features of the β-enaminones 1–3 were assigned by NMR. β-Enaminones 1, and 2 were assigned by single crystal X-ray diffraction technique. The intermolecular interactions in the crystal structures were analyzed quantitatively using Hirshfeld analysis. The Cl…H and O…H hydrogen bonds are common in both compounds while the C-H…π and N…H contacts are more significant in 2 than 1. DFT studies were investigated to show the electronic and spectroscopic properties (NMR and UV-Vis) of the studied systems. peerReviewed

The gem-aminals of 1,2-dimorpholinoethane (1) and 1-morpholino-3-morpholinium bromide propane (2) were synthesized by reaction of two molar ratio of morpholine with the halogenating agents in the presence of basic condition (K2CO3) in acetone at room temperature (RT) overnight. The structures of the centro-symmetric compound 1 and the morpholinium salt derivative 2 were assigned unambiguous by single crystal X-ray diffraction analysis and compared with the 1,2-di(pyrrolidin-1-yl)ethane 3 and 1,2-di(piperidin-1-yl)ethane 4. The 1,2-dimorpholinoethane molecule has a center of symmetry at the midpoint of the C-C bond of the ethyl moiety leading to two equivalent halves. It crystallized in monoclinic crystal system and P21/n space group, while the unit cell parameters are determined to be a = 6.0430(3), b = 8.0805(3), c = 11.1700(4) &Aring, and &beta, = 97.475(2)&deg, with unit cell volume of 540.80(4) &Aring, 3 and Z = 2 at 170(2) K. The less symmetric analogue 2 crystallized in the lower space group P21 with unit cell parameters of a = 6.37450(10), b = 11.1378(2), c = 9.6549(2) &Aring, = 93.358(2)&deg, while the unit cell volume is 684.30(2)&Aring, 3 at 120(2) K. Using Hirshfeld analysis, the molecules of 1 are mainly packed by weak N&hellip, H (4.2%), O&hellip, H (16.8%), and H&hellip, H (79.0%) interactions. In contrast, the molecules of 2 are packed by significantly short O&hellip, H (14.4%) and Br&hellip, H (11.6%) interactions in addition to the relatively long H&hellip, H (73.3%) interactions. DFT calculations predicted the molecular geometry of the studied compounds showing a good agreement with the experimental X-ray structures. Due to symmetry considerations, compounds 1, 3, and 4 are nonpolar with zero dipole moment, while the less symmetric molecule 2 has a dipole moment of 6.914 Debye. Their electronic aspects, such as natural population charges, HOMO, and LUMO energies as well as the corresponding reactivity descriptors, were also calculated and discussed.

An efficient synthetic approach for the construction of fluorine‐containing piperidine γ‐amino acid derivatives has been developed. The synthetic concept was based on oxidative ring opening of an unsaturated bicyclic γ‐lactam (Vince‐lactam) through its ring C=C bond, followed by double reductive amination of the diformyl intermediate performed with various fluoroalkylamines. The method has been extended towards the access of alkylated and perfluoroalkylated substances and for γ‐lactam derivatives. The transformations proceeded with stereocontrol: the configuration of the stereocenters in the products were predetermined by the configuration of the chiral centers of the starting γ‐lactam. The method could be extended for the access to enantiopure piperidine γ‐amino esters. peerReviewed

2,5-disubstituoitujen pyrrolidiinien enantioselektiivistä synteesiä on tutkittu paljon, sillä pyrrolidiinirakenne löytyy monista alkaloideista ja on täten tärkeä osa luonnonainesynteesiä. Lisäksi ne toimivat tärkeinä asymmetrisen synteesin työkaluina. Erityisen kiinnostavia tässä suhteessa ovat erilaiset trans-2,5-bisaryylipyrrolidiinit katalyyttisten ominaisuuksiensa vuoksi. Tässä tutkielmassa käydään läpi eräitä tapoja niiden syntetisoimiseksi. Tutkielmassa keskitytään erityisesti trans-2,5-difenyylipyrrolidiinin enantioselektiiviseen synteesiin.