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Kato Y., Otomura N., Hirano K., et al. Synthesis of DPPP- And DPPPEN-Type Bidentate Ligands by Ring-Opening Diphosphination of Methylene- And Vinylcyclopropanes under Visible-Light-Promoted Photoredox Catalysis. Journal of Organic Chemistry. 85(9), 5981-5994, (2020), 1 May 2020; © 2020 American Chemical Society. https://doi.org/10.1021/acs.joc.0c00417., A ring-opening diphosphination of methylene- and vinylcyclopropanes with tetraaryldiphosphines (Ar2P-PAr2) has been developed to afford the corresponding 1,3-diphenylphosphinopropane- and 1,3-diphenylphosphinopentane-type bidentate ligands, respectively. The reaction proceeds under bromine cation-initiated, visible-light-promoted photoredox catalysis at ambient temperature. Owing to the ready availability of functionalized diphosphines, the electronically diverse MeO- and CF3-substituted bidentate ligands are also easily prepared.

This is the accepted version of the following article: Matsude A., Hirano K., Miura M.. Palladium-Catalyzed Intramolecular Mizoroki-Heck-Type Reaction of Diarylmethyl Carbonates. Advanced Synthesis and Catalysis 362, 518 (2020), which has been published in final form at https://doi.org/10.1002/adsc.201901398. This article may be used for non-commercialpurposes in accordance with the Wiley Self-ArchivingPolicy [https://authorservices.wiley.com/author-resources/Journal-Authors/licensing/self-archiving.html], A palladium-catalyzed intramolecular Mizoroki-Heck-type reaction of diarylmethyl tert-butyl carbonates has been developed. The reaction proceeds under external base-free, neutral conditions to form the corresponding methyleneindanes in good yields only with liberation of CO2 and tBuOH. The resulting exo-methylene moiety is reactive and thus a good synthetic handle for further manipulations. Additionally, the asymmetric synthesis is also possible through a Pd/chiral Mandyphos ligand-mediated kinetic resolution. To the best of our knowledge, this is the first successful example of catalytic enantioselective Mizoroki-Heck-type reaction of secondary benzyl electrophiles. (Figure presented.).

This is the peer reviewed version of the following article: Moon S., Kato M., Nishii Y., et al. Synthesis of Benzo[b]thiophenes through Rhodium-Catalyzed Three-Component Reaction using Elemental Sulfur. Advanced Synthesis and Catalysis 362, 1669 (2020); which has been published in final form at https://doi.org/10.1002/adsc.202000112. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited., A benzo[b]thiophene synthesis by Rh-catalyzed three-component coupling reaction of arylboronic acids, alkynes, and elemental sulfur (S8) is developed. A notable feature of this protocol is that the thienannulation (thiophene annulation) proceeds with high regioselectivity via the sequential alkyne insertion, C−H activation, and then sulfur atom transfer to the metallacycle intermediate. In a similar manner, dibenzothiophenes can be synthesized from the parent biarylboronic acids and S8. (Figure presented.).

A copper-catalyzed regioselective hydrodefluorination of 1-trifluoromethylalkenes with hydrosilanes has been developed. The copper catalysis is compatible with several functional groups, including alkyl chloride, ether, ester, nitrile, and imide moieties, to form the corresponding gem-difluoroalkenes in good yields. Additionally, asymmetric induction is also possible by using the chiral DTBM-SEGPHOS ligand, and gem-difluoroalkene with point chirality at the allylic position is obtained with high enantioselectivity.

Nishii Y., Miura M.. Cp*M-Catalyzed Direct Annulation with Terminal Alkynes and Their Surrogates for the Construction of Multi-Ring Systems. ACS Catalysis. 10(17), 9747-9757, (2020), 4 September 2020; ©2020 American Chemical Society. https://doi.org/10.1021/acscatal.0c02972., Transition-metal-catalyzed C–H activation followed by oxidative cyclization with unsaturated coupling partners has been a valuable synthetic tool for the multi-ring molecular scaffolds. This Perspective introduces the recent progress on the Cp*M-catalyzed (M = Co, Rh, and Ir) oxidative direct annulation of functionalized arenes with terminal alkynes and their equivalents through C–H bond cleavage. The highlighted examples are categorized according to the ten different types of reagents used in the transfor-mations. The representative conditions, selected examples of the reaction scope, and key mechanistic aspects are briefly summarized.

Mihara G., Ghosh K., Nishii Y., et al. Concise Synthesis of Isocoumarins through Rh-Catalyzed Direct Vinylene Annulation: Scope and Mechanistic Insight. Organic Letters. 22(14), 5706-5711, (2020), 17 July 2020; ©2020 American Chemical Society. https://doi.org/10.1021/acs.orglett.0c02112., Transition-metal-catalyzed activation of inert C–H bonds and subsequent C–C bond formation have emerged as pow-erful synthetic tools for the synthesis of elaborate cyclic molecules. In this report, we introduce an efficient synthetic method of 3,4-unsubstituted isocoumarins adopting an electron deficient CpERh complex as the catalyst. The use of vinylene carbonate as a vinylene transfer reagent enables the direct construction of isocoumarins from readily available benzoic acids, without any external oxidants as well as bases. The reaction mechanism is evaluated by computational analysis to find an unprecedented “rhodium shift” event within the catalytic cycle.

Mihara G., Noguchi T., Nishii Y., et al. Rhodium-catalyzed annulative coupling of isothiazoles with alkynes through n-s bond cleavage. Organic Letters. 22(2), 661-665, (2020), 17 January 2020; ©2020 American Chemical Society. https://doi.org/10.1021/acs.orglett.9b04437., A Rh(III)-catalyzed annulative coupling of 3,5-diarylisothiazoles and alkynes is reported. The N–S bond in the isothi-azole ring acts as an internal oxidant to regenerate the Rh(III) species in combination with an external Cu(II) oxidant, and the corre-sponding 1:2 coupling products are obtained. The remarkable difference in the reaction outcome between isothiazoles and the relevant isoxazoles has been investigated by DFT calculations, revealing that the relative stability of the enolate intermediates dictates the product selectivity.

A site-selective direct CH arylation protocol for the triptycene skeleton is developed using copper catalyst and diaryliodonium reagents. With the aid of directing groups, C₃-symmetric trisubstituted triptycenes are selectively synthesized, and the structure was determined by X-ray diffraction analysis. Further derivatization of the installed bromo functionalities is also described.

Hirano K., Miura M., Xu S.. Pd-catalyzed regioselective C−H alkenylation and alkynylation of allylic alcohols with the assistance of a bidentate phenanthroline auxiliary. Organic Letters. 22(22), 9059-9064, (2020), 20 November 2020; © 2020 American Chemical Society. https://doi.org/10.1021/acs.orglett.0c03444., A Pd-catalyzed regioselective C−H alkenylation of allylic alcohols with electron-deficient alkenes has been developed. The key to success is the introduction of bidentately coordinating phenanthroline directing group, which enables the otherwise challenging and regioselective C−H activation at the proximal alkenyl C−H bonds over the conceivably competitive allylic C−O bond activation. The same Pd/phenanthroline system is efficient for the C−H alkynylation of allylic alcohols with alkynyl bromides.

Hirano K., Miura M., Asai K.. Divergent synthesis of isonitriles and nitriles by palladium- catalyzed benzylic substitution with TMSCN. Journal of Organic Chemistry. 85(19), 12703-12714, (2020), 2 October 2020; © 2020 American Chemical Society. https://doi.org/10.1021/acs.joc.0c01861., Ligand-controlled palladium-catalyzed divergent synthesis of isonitriles and nitriles from benzylic carbonates and TMSCN has been developed. The BINAP- or DPEphos-ligated palladium catalyst selectively provides the corresponding benzylic isonitriles, whereas their regioisomers, benzylic nitriles, are formed exclusively under phosphine ligand-free conditions. Mechanistic studies reveal that isonitrile is the primary product under both conditions, but it is isomerized into nitrile in the absence of ancillary phosphine ligands.

Masahiro Miura, Ryo Wakita, Takuya Iwasaki Department of Ophthalmology, Tokyo Medical University, Ibaraki Medical Center, Inashiki, Ibaraki 3000395, JapanCorrespondence: Masahiro MiuraDepartment of Ophthalmology, Tokyo Medical University, Ibaraki Medical Center, 3-20-1 Chuo, Ami, Inashiki, Ibaraki 300395, JapanTel +81-298871161Fax +81-298877656Email m-miura@tokyo-med.ac.jpPurpose: Low power mode (LPM) can be used for subthreshold retinal laser treatment by simply adjusting the laser parameters. Herein, we report the use of a modified LPM laser treatment for four cases of central serous chorioretinopathy (CSCR).Patients and Methods: We retrospectively reviewed the medical records of four patients (four eyes) with persistent CSCR who underwent modified LPM laser for leakage. The laser power was first titrated with a barely visible burn, and then treatment was applied using 33% laser energy by manually adjusting the laser power and duration.Results: Serous retinal detachment completely resolved in all cases by 2 months after treatment. Autofluorescence images did not show any specific changes induced by laser burns.Conclusion: A modified LPM laser may provide a feasible treatment for persistent CSCR.Keywords: central serous chorioretinopathy, subthreshold laser, low power mode, photocoagulation