Max Martin

Abstract

Abstract

Not a matter of IF but when: Described is the preparation of the last elusive indenofluorene (IF) regioisomer. While the body of circumstantial spectroscopic data support formation of the highly reactive triplet diradicaloid, definitive structural proof is provided by X-ray diffraction analysis of crystals of the dianion, obtained by reduction of the indeno[1,2-a]fluorene with Cs metal.

[Communication]
Justin J. Dressler, Zheng Zhou, Jonathan L. Marshall, Ryohei Kishi, Shota Takamuku, Zheng Wei, Sarah N. Spisak, Masayoshi Nakano, Marina A. Petrukhina, Michael M. Haley
Angew. Chem. Int. Ed., October 24, 2017, https://doi.org/10.1002/anie.201709282 Read article

Case closed: Oxidative fusion reactions of ortho-phenylene-bridged cyclic oligomers furnished novel closed heterohelicenes in a selective manner. X-ray diffraction analysis revealed the structures to be the closed pentaaza[9]helicene and hexathia[9]/[5]helicene, rare examples of a heteroaromatic closed helicene and an asymmetric double helicene, respectively. Their optical properties were studied and the enantiomeric separation was performed by chiral-phase HPLC.

[Communication]
Fengkun Chen, Takayuki Tanaka, Yong Seok Hong, Tadashi Mori, Dongho Kim, Atsuhiro Osuka
Angew. Chem. Int. Ed., October 10, 2017, https://doi.org/10.1002/anie.201708429 Read article

The HF-zipping strategy allows an unprecedentedly challenging transformation to be performed. It consists of “zipping” virtually linear fluorinated oligophenylenes together to give “preprogrammed” nanographenes via domino-like cyclodehydrofluorination. In their Communication (DOI: 10.1002/anie.201707272), A.-K. Steiner and K. Y. Amsharov demonstrate that fluorine positions in the precursor structure unambiguously dictate the running of the “zipping-program” leading exclusively to the target atomically precise nanographene.

[Cover Picture]
Ann-Kristin Steiner, Konstantin Y. Amsharov
Angew. Chem. Int. Ed., October 11, 2017, https://doi.org/10.1002/anie.201710002 Read article

Nature Chemistry. doi:10.1038/nchem.2839

Authors: Ben S. Pilgrim, Derrick A. Roberts, Thorsten G. Lohr, Tanya K. Ronson & Jonathan R. Nitschke

Two coordination cages have been devised that undergo covalent modification during a cascade of two orthogonal Diels–Alder reactions. This results in increased lipophilicity for the second cage, enabling its phase transfer and separation from the first. The trigger, relay and inhibition features of this cascade system mimic key aspects of natural post-translational modification cascades.

A bowl-shaped antiaromatic molecule was synthesized by deformation of a planar antiaromatic π-conjugation system upon insertion of palladium into the small cavity of a metal-free norcorrole. The latter was prepared from demetalation of a copper norcorrole obtained from the intramolecular coupling of a bis(diiododipyrrin) copper complex with copper thiophenecarboxylate.

[Communication]
Tsubasa Yonezawa, Siham A. Shafie, Satoru Hiroto, Hiroshi Shinokubo
Angew. Chem. Int. Ed., August 16, 2017, https://doi.org/10.1002/anie.201706134 Read article

Porphyrin Tautomerism In their Communication on page 10088 ff., A. Ghosh et al. report the isolation of the elusive cis tautomer of a free-base porphyrin.

[Frontispiece]
Kolle E. Thomas, Laura J. McCormick, Hugo Vazquez-Lima, Abhik Ghosh
Angew. Chem. Int. Ed., August 09, 2017, https://doi.org/10.1002/anie.201783461 Read article

The latest ultrahigh-field NMR spectrometers are a huge technological challenge that require large financial investments. In his Guest Editorial, Harald Schwalbe justifies the need for spectrometers with higher magnetic field strengths. The important results from previous generations of high-field NMR spectrometers are discussed, and research areas are identified that will benefit from the latest spectrometers.

[Editorial]
Harald Schwalbe
Angew. Chem. Int. Ed., July 24, 2017, https://doi.org/10.1002/anie.201705936 Read article

Bastian Dumslaff, Anna N. Reuss, Dr. Manfred Wagner, Prof. Dr. Xinliang Feng, Dr. Akimitsu Narita, Prof. Dr. George Fytas and Prof. Dr. Klaus Müllen

Essentially strain-free and thermally stable paddlewheel polyphenylenes consisting of two covalently interlocked cyclohexa-m-phenylenes have been synthesized. Tuning of the solubility allowed the hierarchical formation of three-dimensional carbon nanostructures to be monitored.

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Qatar blockade hits helium supply

Nature 547, 7661 (2017). http://www.nature.com/doifinder/10.1038/547016a

Author: Declan Butler

Researchers braced for shortages as Gulf state forced to close its refineries.

Polyaromatic molecular peanuts

Nature Communications, Published online: 28 June 2017; doi:10.1038/ncomms15914

The complex, multicomponent structures often found in nature are difficult to mimic synthetically. Here, the authors assemble a molecular analogue of a peanut through coordinative and π-stacking interactions, in which a polyaromatic double capsule ‘pod’ held together by metal ions encapsulates fullerene ‘beans’.