Molecular junctions incorporating pristine and cross-linked aromatic self-assembled monolayers (SAMs) are fabricated and investigated. A two-terminal setup composed of a eutectic Ga–In (EGaIn) top electrode and the gold substrate on which SAMs are prepared as a bottom electrode was used to characterize the charge transport. SAMs of phenylthiol (PT), biphenylthiol (BPT), p-terphenylthiol (TPT), and p-quaterphenylthiol (QPT) are then irradiated with low-energy electrons and converted into carbon nanomembranes (CNMs). A comparison of charge transport through SAMs and CNMs reveals a decrease of conductance of CNM-based junctions by 1 order of magnitude, as well as a conversion of asymmetric junctions with SAMs into symmetric junctions with CNMs, which could be attributed to the decoupling of CNMs from the Au substrate and the partial loss of aromaticity of CNMs after irradiation. Transition voltage spectroscopy (TVS) was also employed to investigate both types of junctions. We observe the length-dependent behavior of transition voltages in both systems and a reduction of transition voltages of CNM-based junctions in comparison to SAM-based junctions.

Ethyl 1-oxo-indane-2-carboxylate with a 1,4-diketone motif gave a benzo[c]azocane-1-one derivative Ϫ an eight-membered ring lactam Ϫ in a bismuth-mediated ring-expansion reaction with methylamine (40 % yield). Yields with other primary amines were significantly lower. The ester function in the heterocyclic product could be saponified to give the free carboxylic acid, which was further amidated with parabromoaniline. The molecular structure of the latter was established by X-ray single-crystal analysis. Benzo[c]azocanones exist in two diastereoisomeric conformations, causing double signal sets in the NMR spectra. Slow interconversion between these conformers was proved by EXSY NMR spectroscopy. Moreover, a conformational analysis by DFT calculations revealed the two diastereoisomers to be boat

Racemic 1,2‐cyclohexanedisulfonic acid was prepared from cyclohexene oxide via the cyclic trithiocarbonate and isolated as its barium salt. Optical resolution was achieved by crystallization with (–)‐(R,R)‐1,2‐cyclohexane diamine; the absolute configuration was established by X‐ray crystallography of this salt, [C6H10(NH3)2][C6H10(SO3)2]. Solid‐state structures were investigated of the racemic acidic sodium disulfonate Na(H5O2)[C6H10(SO3)2] and the optically active disulfonates Na2[C6H10(SO3)2]·1.8H2O and Ag(NH2Me2)[C6H10(SO3)2].

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Synthesis of Benzo[c]azocanones and Indeno[1,2-b]pyrroles from Oxoindanecarboxylates. -A series of heterocycles (IV) is obtained by bismuth-catalyzedPaal-Knorr synthesis from phenacyl-1-indanone. Benzo[c]azocines (VI) are formed by bismuth-catalyzed ring expansions of indanone-derived 1,4-diketone and primary amines. The products exist as two diastereomeric conformers. Efforts to synthesize ε-caprolactams from four-membered ring oxo ester (VII) are unsuccessful. -(BEHLER, F.; HABECKER, F.; SAAK, W.; KLUENER, T.; CHRISTOFFERS*, J.; Eur. J. Org. Chem. 2011, 22, 4231-4240, http://dx.