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Background: The superficial radial artery (SRA) is a rare congenital anomaly in the forearm. However, it can be detected incidentally via trauma, intraoperative findings, angiography, or ultrasonography. In addition, intra-arterial infusion of intravenous medications and difficulties in radial artery catheterization may occur in cases of the SRA.Methods: Between December 2016 and July 2020, anomalous branches of radial arteries were found incidentally in nine patients at the preoperative visit and identified during ultrasound-guided radial artery puncture in 21 patients when radial artery catheterization using the palpation method proved difficult. Ultrasound examinations were performed for diagnosis and evaluation of these 30 patients.Results: All anomalous branches of the radial artery were SRAs; 11 (37%), 13 (43%), 6 (20%) were present on the right side, on the left side, and bilaterally, respectively. All SRAs ran close to the cephalic vein. The vascular diameters of the radial arteries were the smallest in the radial artery distal to the SRA bifurcation (followed by in the SRA) and the largest in the radial artery proximal to the bifurcation (p< .001). In two cases, color Doppler study revealed that both the blood flow and color Doppler signal of the SRA disappeared with compression of the radial artery proximal to the SRA bifurcation.Conclusions: Because the SRA runs very close to the cephalic vein, a tourniquet applied to the arm may easily lead to intravenous catheter misplacement into the SRA. In addition, the small radial artery distal to the SRA bifurcation causes difficulty in radial artery catheterization. Furthermore, SRA cases may have falsely normal Allen’s test results. Therefore, the authors recommend that the SRA must be identified before vascular puncture for safe vascular catheterization in the forearm.

The direct oxidative coupling of 2-amino- and 2-hydroxybenzoic acids with internal alkynes proceeds efficiently in the presence of a rhodium/copper catalyst system under air to afford the corresponding 8-substituted isocoumarin derivatives, some of which exhibit solid-state fluorescence. Depending on conditions, 4-ethenylcarbazoles can be synthesized selectively from 2-(arylamino)benzoic acids. The oxidative coupling reactions of heteroarene carboxylic acids as well as aromatic diacids with an alkyne are also described.

The cross-addition of terminal silylacetylenes to γ-arylated propargyl amines occurs efficiently via C−H cleavage by using either a nickel or rhodium catalyst. Taking advantage of the catalyst-controlled switching of regioselectivity in the reaction, both the 2- and 3-alkynylallylamines are readily accessible from the same starting materials.

ABSTRACTBreeding of sugi (Cryptomeria japonica) started with the selection of first generation plus-trees in the 1950s in Japan. The initial aim of the breeding program was to improve growth performance, and the aim has been extended to tolerance to adverse meteorological conditions, amelioration of wood properties, mitigation of pollinosis, and adaptation to climate change. These changes have arisen in response to shifts in social demands from timber production to management of diverse forest functions over time. Currently, the focus of C. japonicabreeding is focusing on the selection and deployment of second-generation plus-tree clones and establishment of breeding populations for the third-generation plus-trees. In this review, these activities and achievements are described, and prospects of the future breeding initiatives, including the feasibility of breeding for climate change, are discussed.

Several title host crystals including guest luminescent compounds exhibit apparent room temperature phosphorescence (RTP) along with fluorescence under atmospheric conditions. The lifetime of RTP is a marked function of the halogen atoms, decreasing in the order of Cl > Br > I, while the phosphorescence efficiency depends on the structural compatibility of the guests in the host crystals.Several title host crystals including guest luminescent compounds exhibit apparent room temperature phosphorescence (RTP) along with fluorescence under atmospheric conditions. The lifetime of RTP is a marked function of the halogen atoms decreasing in the order of Cl > Br > I, while the phosphorescence efficiency depends on the structural compatibility of the guests in the host crystals.

A palladium-catalyzed cross-coupling reaction of diarylmethanol derivatives with diborylmethane has been developed. The reaction proceeds chemoselectively to deliver the corresponding homobenzylic boronates in good yields.

A copper-catalyzed silylamination of α,β-unsaturated esters with silylboranes and hydroxylamines has been developed to afford the corresponding β-silyl-α-amino acid derivatives, which are of great interest in medicinal and pharmaceutical chemistry. Additionally, by using a suitable chiral bisphosphine ligand, the asymmetric induction is possible, delivering the optically active β-silyl-α-amino acids with synthetically acceptable diastereomeric ratios (55:45–82:18 dr) and high enantiomeric ratios (81:19–99:1 er).

Nitrogen (N) is ubiquitously found in bioactive molecules, pharmaceutical agents, and organic functional materials. Accordingly, development of new C–N bond-forming catalysis has been one of the long-standing research subjects in synthetic organic chemistry. In this Perspective, recent advances in highly selective amination reactions with electrophilic amination reagents are described: by taking advantage of the concept of nitrogen umpolung, otherwise challenging aminofunctionalizations, such as hydroamination, aminoboration, and carboamination, of readily available feedstock-like alkenes and alkynes are possible, giving densely functionalized complex and often chiral alkylamines with high selectivity. The scope, limitations, and reaction mechanism are briefly summarized.

A new family of heavy-atom-free room-temperature phosphorescent compounds, dibenzobenzodithiophenes (DBDTs) have been synthesized and characterized. The afterglow of the regioisomeric compounds has been investigated in a polymer matrix. Furthermore, it has been revealed that much simpler dibenzothiophenes display room-temperature phosphorescence in a polymeric matrix.A new family of heavy-atom-free room-temperature phosphorescent compounds, dibenzobenzodithiophenes (DBDTs) have been synthesized and characterized. The afterglow of the regioisomeric compounds has been investigated in a polymer matrix. Furthermore, it has been revealed that much simpler dibenzothiophenes display room-temperature phosphorescence in a polymeric matrix.

A Cu-mediated ortho-selective C–H cyanation of phenols with ethyl cyanoformate as the cyano source has been developed. The key to success is the introduction of 4,4′-di-tert-butyl-2,2′-bipyridine (dtbpy) bidentate auxiliary on the phenol oxygen, which is easily attachable, detachable, and recyclable. The newly developed protocol is tolerant of several carbonyl functional groups, which are incompatible with previous Lewis-acid-promoted cyanation of phenols.A Cu-mediated ortho-selective C–H cyanation of phenols with ethyl cyanoformate as the cyano source has been developed. The key to success is the introduction of 4,4′-di-tert-butyl-2,2′-bipyridine (dtbpy) bidentate auxiliary on the phenol oxygen, which is easily attachable, detachable, and recyclable. The newly developed protocol is tolerant of several carbonyl functional groups, which are incompatible with previous Lewis-acid-promoted cyanation of phenols.

Regioselective direct functionalization of an indole benzenoid fragment has been a significant challenge because of its inherently lower reactivity. In this report, we introduce a Rh-catalyzed C7-selective alkenylation of indole derivatives using a new sulfur directing group N-SCy. A notable feature of this system is that the directing group is readily installed to the indoles and easily removed after the catalysis under mild conditions.

ABSTRACTMacroautophagy/autophagy plays a critical role in the pathogenesis of various human diseases including neurodegenerative disorders such as Parkinson disease (PD) and Huntington disease (HD). Chemical autophagy inducers are expected to serve as disease-modifying agents by eliminating cytotoxic/damaged proteins. Although many autophagy inducers have been identified, their precise molecular mechanisms are not fully understood because of the complicated crosstalk among signaling pathways. To address this issue, we performed several chemical genomic analyses enabling us to comprehend the dominancy among the autophagy-associated pathways followed by an aggresome-clearance assay. In a first step, more than 400 target-established small molecules were assessed for their ability to activate autophagic flux in neuronal PC12D cells, and we identified 39 compounds as autophagy inducers. We then profiled the autophagy inducers by testing their effect on the induction of autophagy by 200 well-established signal transduction modulators. Our principal component analysis (PCA) and clustering analysis using a dataset of “autophagy profiles” revealed that two Food and Drug Administration (FDA)-approved drugs, memantine and clemastine, activate endoplasmic reticulum (ER) stress responses, which could lead to autophagy induction. We also confirmed that SMK-17, a recently identified autophagy inducer, induced autophagy via the PRKC/PKC-TFEB pathway, as had been predicted from PCA. Finally, we showed that almost all of the autophagy inducers tested in this present work significantly enhanced the clearance of the protein aggregates observed in cellular models of PD and HD. These results, with the combined approach, suggested that autophagy-activating small molecules may improve proteinopathies by eliminating nonfunctional protein aggregates.Abbreviations:ADK: adenosine kinase; AMPK: AMP-activated protein kinase; ATF4: activating transcription factor 4; BECN1: beclin-1; DDIT3/CHOP: DNA damage inducible transcript 3; EIF2AK3/PERK: eukaryotic translation initiation factor 2 alpha kinase 3; EIF2S1/eIF2α: eukaryotic translation initiation factor 2 subunit alpha; ER: endoplasmic reticulum; ERN1/IRE1α: endoplasmic reticulum to nucleus signaling 1; FDA: Food and Drug Administration; GSH: glutathione; HD: Huntington disease; HSPA5/GRP78: heat shock protein family A (Hsp70) member 5; HTT: huntingtin; JAK: Janus kinase, MAP1LC3B/LC3: microtubule associated protein 1 light chain 3 beta; MAP2K/MEK: mitogen-activated protein kinase kinase; MAP3K8/Tpl2: mitogen-activated protein kinase kinase kinase 8; MAPK: mitogen-activated protein kinase; MPP+: 1-methyl-4-phenylpyridinium; MTOR: mechanistic target of rapamycin kinase; MTORC: MTOR complex; NAC: N-acetylcysteine; NGF: nerve growth factor 2; NMDA: N-methyl-D-aspartate; PCA: principal component analysis; PD: Parkinson disease; PDA: pancreatic ductal adenocarcinoma; PIK3C3: phosphatidylinositol 3-kinase catalytic subunit type 3; PMA: phorbol 12-myristate 13-acetate; PRKC/PKC: protein kinase C; ROCK: Rho-associated coiled-coil protein kinase; RR: ribonucleotide reductase; SIGMAR1: sigma non-opioid intracellular receptor 1; SQSTM1/p62: sequestosome 1; STK11/LKB1: serine/threonine kinase 11; TFEB: Transcription factor EB; TGFB/TGF-β: Transforming growth factor beta; ULK1: unc-51 like autophagy activating kinase 1; XBP1: X-box binding protein 1.

A copper-mediated dehydrogenative C–H/C–H biaryl coupling of phenols and 1,3-azoles has been developed. The key to its success is the introduction of a bipyridine-type bidentate auxiliary, 4,4′-di(tert-butyl)-2,2′-bipyridine, on the phenol oxygen, which is readily prepared and easily attachable, detachable, and recyclable. The reaction proceeds smoothly in the presence of copper salt alone to form the corresponding phenol-azole heterobiaryls, which are prevalent motifs in functional molecules such as excited-state intramolecular proton transfer materials.

Herein, we disclose a unique directing effect of 9-substituted triptycenes in electrophilic substitution to achieve the regioselective functionalization of the triptycene core. The Hirshfeld population analysis was adopted to predict the selectivity in electrophilic substitution. TMS and t-Bu groups were found to considerably accelerate the reaction at C2 positions to produce C3-symmetric isomers. Correlation between distortion and charge distribution within benzene rings was systematically examined.

Herein we report an efficient synthetic method for the electrophilic trifluoromethylthiolation of aromatic compounds. The key is to use triptycenyl sulfide (Trip-SMe) and TfOH to enhance the electrophilicity of SCF3fragment through the formation of sulfonium intermediates. This method enables direct installation of an SCF3group onto unactivated aromatics at room temperature, adopting a commercially available saccharin-based reagent. Preliminary DFT calculation was carried out to investigate the substitution effect on the catalytic activity.

A rhodium-catalyzed C4-selective C–H alkenylation of 3-carboxy-2-pyridones with styrenes has been developed. The carboxylic group at the C3 position works as the traceless directing group, and the corresponding C4-alkenylated 2-pyridones are obtained exclusively with concomitant decarboxylation. Unlike the reported procedures, the exclusive C4 selectivity is uniformly observed even in the presence of potentially more reactive C–H bonds at the C5 and C6 positions. By using this strategy, the multiply substituted 2-pyridone can be prepared via sequential C–H functionalization reactions.

Pure organic materials with the circularly polarized luminescence (CPL) property have attracted significant research interest over the past few decades. In this study, a series of axially chiral bibenzo[b]carbazole derivatives were synthesized by adopting palladium- and iridium-catalyzed direct C–H functionalization reactions as the key steps. These compounds exhibited CPL characteristics with considerably large dissymmetry factors up to 2.81 × 10–2in the solid state, indicating the formation of well-ordered aggregates.

A rhodium-catalyzed oxidative annulation of benzimidates with elemental sulfur for the direct construction of isothiazole rings is reported. The proposed reaction mechanism involving Rh(I)/Rh(III) redox is supported by a stoichiometric reaction of metallacycle species as well as DFT calculations. This method is also applicable to selenium cyclization to produce isoselenazole derivatives. The alkoxy substituent at C3 can be used for further functionalization of the azole core.

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.

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.

A copper-mediated, phenanthroline-directed highly ortho-selective C–H sulfenylation of phenols with diaryl disulfides proceeds to form the corresponding unsymmetrical diaryl sulfides in good yield. The key to success is the introduction of a phenanthroline directing group of the bidentate-chelating nature, which is easily attachable, detachable, and even recyclable. Moreover, the same strategy is applicable to the C–H selenation, giving the diaryl selenides with high efficiency and regioselectivity.

A unique strategy for the fabrication of room temperature phosphorescent guest/host crystals, which consist of π-extended cyclized guests and their mother uncyclized flexible brominated hosts, is reported. Combinations of bisbenzofuropyrazines/bis(2-bromophenoxy)pyrazines are the examples. Judicious choice of the guest/host pair allows to create highly phosphorescent crystals.A unique strategy for the fabrication of room temperature phosphorescent guest/host crystals, which consist of π-extended cyclized guests and their mother uncyclized flexible brominated hosts, is reported. Combinations of bisbenzofuropyrazines/bis(2-bromophenoxy)pyrazines are the examples. Judicious choice of the guest/host pair allows creation of highly phosphorescent crystals.

Transition-metal-catalyzed activation of inert C–H bonds and subsequent C–C bond formation have emerged as powerful 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.

Site-selective direct functionalization of an indole benzenoid core has been a great challenge due to its inherently poor reactivity. We herein demonstrate an iridium-catalyzed C4-selective acylmethylation of indoles using α-carbonyl sulfoxonium ylides as carbene precursors. This method exhibits high efficiency and broad functional group compatibility. The directing group was easily removed or converted to other functionalities after the catalysis. The potential synthetic utility of the coupling products was highlighted by constructing medium-sized polycyclic indoles.

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

A site-selective direct C–H 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.A site-selective direct C–H arylation protocol for 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 is determined by X-ray diffraction analysis. Further derivatization of the installed bromo functionalities are also described.

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.

Transition-metal-catalyzed C–H activation followed by oxidative annulation with alkynes has been an efficient synthetic tool for the assembly of various polyaromatic scaffolds. Despite the substantial progress in this field, it is still a significant challenge to achieve the synthesis of nonsubstituted vinylene-fused compounds. In this contribution, we report a Rh-catalyzed C–H/C–H vinylene cyclization adopting vinylene carbonate as a “vinylene transfer” agent. This protocol achieves the direct annulative π-extension of imidazole- and pyrazole-fused aromatics.

We have developed a new strategy for the generation of phosphenium dication equivalents from readily available phosphinic acids and Tf2O. The in situ-generated dication equivalents can be readily coupled with simple (hetero)biaryls to form the corresponding dibenzophospholes directly. This protocol can also be applied to the concise synthesis of six- and seven-membered phosphacycles as well as the largely π-extended heteroacene derivatives, which are of great interest in the field of organic functional materials.

A palladium-catalyzed Mizoroki–Heck-type cyclization/Suzuki–Miyaura cross-coupling cascade of diarylmethyl carbonates with arylboronic acid derivatives has been developed to deliver the corresponding 1,2-disubstituted indanes in good yields with high diastereoselectivity (trans/cis> 20:1). The key to achieve the high chemoselectivity and stereoselectivity is the use of the tris[3,5-di(tert-butyl)-4-methoxyphenyl]phosphine (DTBMP) ligand of remote steric hindrance. Moreover, the asymmetric synthesis is possible by the enantiospecific, stereoinvertive reaction of the optically active starting substrates to form the chiral indanes with high stereochemical fidelity (>98% es).

A Lewis base catalyst Trip-SMe (Trip = triptycenyl) for electrophilic aromatic halogenation using N-halosuccinimides (NXS) is introduced. In the presence of an appropriate activator (as a noncoordinating-anion source), a series of unactivated aromatic compounds were halogenated at ambient temperature using NXS. This catalytic system was applicable to transformations that are currently unachievable except for the use of Br2or Cl2: e.g., multihalogenation of naphthalene, regioselective bromination of BINOL, etc. Controlled experiments revealed that the triptycenyl substituent exerts a crucial role for the catalytic activity, and kinetic experiments implied the occurrence of a sulfonium salt [Trip-S(Me)Br][SbF6] as an active species. Compared to simple dialkyl sulfides, Trip-SMe exhibited a significant charge-separated ion pair character within the halonium complex whose structural information was obtained by the single-crystal X-ray analysis. A preliminary computational study disclosed that the π system of the triptycenyl functionality is a key motif to consolidate the enhancement of electrophilicity.

A Rh(III)-catalyzed annulative coupling of 3,5-diarylisothiazoles and alkynes is reported. The N–S bond in the isothiazole ring acts as an internal oxidant to regenerate the Rh(III) species in combination with an external Cu(II) oxidant, and the corresponding 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.

Trioxa- and trithia-truxene derivatives, 3,8,13- (para) and 2,7,12- (meta) tri-tert-butylated benzo[1,2-b:3,4-b':5,6-b'']-trifuran and -tris[1]benzothiophenes (p-tBuTxO, m-tBuTxO, p-tBuTxS, and m-tBuTxS), have been prepared by palladium-catalyzed intramolecular triple dehydrogenative cyclization. While these compounds are soluble in common organic solvents, they have high melting points, mostly more than 300 °C. m-tBuTxO shows a substantial solid state UV fluorescence with a higher quantum efficiency than p-tBuTxO. Both p-tBuTxS and m-tBuTxS, however, exhibit only weak fluorescence in both solution and solid state (the ?maxof emission in solid state specifically depends on the substitution pattern), but obvious blue phosphorescence is observed in PMMA film under vacuum at r.t. as well as in MeCy at 77 K, which is attributable to the heavy atom effect of sulfur. Meanwhile, p-tBuTxS exhibits a higher hole mobility compared with that of m-tBuTxS in the evaluation of thin-film FET characteristics. These results are discussed in terms of intrinsic molecular structures and arrangements determined by X-ray crystallography.The tert-butyl-substituted oxa- and thia-truxenes are highly soluble, while have high melting points. The oxa-compounds exhibit UV fluorescence and long-life blue phosphorescence, whereas relatively strong phosphorescence is observed with the thia-analogues. The solid state optelectronic properties of the thia-compounds significantly depend on the substitution pattern.

Substantial research interests have been focused on cyclic p-conjugated molecules owing to their unique chemical and physical properties. By constructing hybrid aromatic arrays within these cyclic systems, new series of composite macrocycles would be provided. Our group has been studying the construction of such hybrids by adopting the palladium-catalyzed direct coupling of heteroaromatics. We herein report the synthesis and characterization of thiophene-thiazole composite macrocycles. X-ray diffraction analyses revealed that some of these coupling products exhibit characteristic helical assemblies in the solid state. Additionally, we synthesized a heteroarene-fused cyclooctatetraene composed of four different heteroaryl fragments.The synthesis and characterization of a series of thiophene-thiazole hybrid macrocyclic compounds through the Pd-catalyzed direct couping are described. The coupling products form characteristic helical assemblies, and among them, the new tetraheteroarylene specifically affords chiral crystals. Additionally, the first synthesis of a tetraarylene composed of four different heteroaryl fragments is achieved.

A compact clinical prototype multi-functional optical coherence tomography (OCT) device for the posterior human eye has been developed. This compact Jones-matrix OCT (JM-OCT) device integrates all components into a single package. Multiple image functions, i.e., scattering intensity, OCT angiography, and the degree of polarization uniformity, are obtained. The device has the capability for measuring local birefringence. Multi-functional imaging of several eyes with age-related macular degeneration is demonstrated. The compact JM-OCT device will be useful for the in vivo non-invasive investigation of abnormal tissues.

ABSTRACTIn order to provide basic information on genetic improvement potential in Cryptomeria japonica(sugi), we estimated genetic parameters, direct and indirect genetic gains and optimum selection ages for growth traits based on the data obtained from 429 progeny test sites located throughout Japan. Medians of narrow-sense heritabilites for height and diameter at breast height (DBH) were ranged in 0.289–0.445 and 0.235–0.276, respectively. The heritability of height significantly increased after the age of 15 years. On the other hand, there were no significant differences among ages in the heritability of DBH. Medians of the age-age genetic correlations were similar when the age differences of the pairs were the same, and tended to decrease as the age differences became larger for both height and DBH. The maximum efficiencies for gain per year when the target age is assumed to be 30 years were obtained at an age of 5 years in height and of 10 years in DBH, respectively. As the values at an age of 5 years in height varied greatly depending on test site, there would likely be selection errors. Thus, the early selection at 1/3 the target age is efficient in sugi.

Treatment of 1,3- and 1,4-bis(3,6-di-tert-butyl-9H-carbazol-9-yl)benzenes with an oxidizing system of Pd(II)/Ag(I) has been found to induce double intramolecular C-H/C-H coupling to give the corresponding highly p-extended polycyclic compounds. In contrast, a singly cyclized product in a different manner has been isolated from the reaction of 1,2-bis(3,6-di-tert-butyl-9H-carbazol-9-yl)benzene. Cardinal optoelectronic properties of the products have also been estimated.1,2-Bis(3,6-di-tert-butyl-9H-carbazol-9-yl)benzenes undergo double or mono cyclization through C-H/C-H coupling in the presence of an oxidizing system of Pd(II)/Ag(I) to produce corresponding structurally intriguing nitrogen-containing polycyclic aromatic compounds that show violet to blue fluorescence.

A solvent‐controlled rhodium‐catalyzed C6‐selective alkenylation and alkylation of 2‐pyridones with acrylates via a pyridine‐directed C−H cleavage was developed. Using DMF as solvent, the C−H alkenylation with acrylates selectively occurs to deliver the corresponding C6‐alkenylated 2‐pyridones in good yields. On the other hand, the C6‐alkylated products are predominantly formed in a more polar and protic solvent, HFIP. Thus, a single set of starting substrates can be divergently transformed to C6‐functionalized 2‐pyridones, which are of potent interest in medicinal and pharmaceutical chemistry. At a fork: A Cp*Rh(III)‐catalyzed, pyridine‐directed C6‐selective C−H alkenylation and alkylation of 2‐pyridones has been developed. Using DMF as solvent, the C−H alkenylation with acrylates occurs selectively to deliver the corresponding C6‐alkenylated 2‐pyridones in good yields. On the other hand, the C6‐alkylated products are predominantly formed in a more polar and protic solvent: HFIP. The observed solvent‐dependent product switching can provide divergent access to the C6‐functionalized 2‐pyridones.

A copper-catalyzed electrophilic amination of gem-diborylalkanes with hydroxylamines has been developed. The key to its success is the use of the Me3Si-modified 1,2-bis(diphenylphosphino)benzene ligand. Additionally, the reactivity of neopentylglycol derivatives compared to that of commonly used pinacol-derived ones is found to be higher, particularly in the case of relatively sterically congested substrates. The copper catalysis presented here enables the first successful catalytic carbon–heteroatom bond forming reaction of gem-diborylalkanes to form the corresponding α-aminoboronic acid derivatives, which are of great interest in medicinal and pharmaceutical chemistry.

A copper-catalyzed regioselective net hydroamination of 1-trifluoromethylalkenes with hydrosilanes and hydroxylamines has been developed. The judicious choice of ligand and additive suppresses the conceivable but undesired β-F elimination of an α-CF3-substituted organocopper intermediate, leading to targeted α-trifluoromethylamines in good yields with excellent regioselectivity. Additionally, with an appropriate chiral bisphosphine ligand, the enantioselective reaction is also possible to deliver optically active α-trifluoromethylamines of high potential in medicinal and pharmaceutical chemistry.

Cu(I)/modified dppbz catalyst systems for the regioselective aminoboration of unactivated terminal alkenes have been developed. The bisphosphine-based Cu catalysis enables the introduction of the readily transformable Bpin group at the more congested internal position and shows better regioselectivity for broader terminal alkenes involving sterically demanding allylbenzenes, which are relatively challenging substrates in the previous IPrCuBr catalysis. Additionally, the second-generation catalyst systems accommodate the exo-methylene-type disubstituted alkenes to deliver the corresponding aminoborated products in good yields with a high regioselectivity.

An Ir(ppy)3-catalyzed vic-diphosphination of styrenes with Me3Si-PPh2and NFSI proceeds under blue LED irradiation to afford the corresponding bis(diphenylphosphino)ethane derivatives without any formation of hydrophosphination byproducts, which are inevitable and problematic under the previous Cu/NHC catalysis. Additionally, the visible-light-promoted photoredox catalysis enables the diphosphination of relatively challenging aliphatic alkenes and β-substituted styrene.

Transition metal-catalyzed aromatic functionalization reactions are highly important for the construction of various organic fine chemicals. In particular, the direct C(sp2)-H bond transformation of (hetero)aromatics is currently recognized to be highly useful in organic synthesis, as it can realize short-step sequences leading to target molecules. We have been studying aromatic cross-coupling reactions through C-H bond activation/cleavage leading to new C-C and C-heteroatom bonds. The research strategies involve directing group (DG) control and utilization of unique properties of reaction substrates and catalysts, which enable efficient regioselective direct coupling reactions. In this account, our recent work is briefly summarized, mainly focused on the synthetic methods of benzo-fused multi-ring heterocyclic compounds of potent interest in pharmaceutical and material chemistry.We have been studying aromatic cross-coupling reactions through C-H bond activation/cleavage leading to new C-C and C-heteroatom bonds. In this account, our recent work is briefly summarized, mainly focused on the development of synthetic methods of multi-ring benzo-fused heterocyclic compounds of potent interest in pharmaceutical and material chemistry.

Functionalized triptycene derivatives have attracted significant research interest because of their potential applications in many research fields. Although the conventional Diels‐Alder reaction of anthracenes with benzynes has been a versatile synthetic tool for functionalized triptycenes, it is hardly possible to control the product regioselectivity. In this report, we demonstrate the selective synthesis of 1,8,13‐trisubstituted triptycenes by Pd‐catalyzed α‐bromination. As for the directing group, SMe group was the most effective to facilitate the halogenation of the proximal three benzene rings. The obtained product was further derivatized through allylation and Rh‐catalyzed hydroboration reactions. Functionalized triptycene derivatives have attracted significant research interest because of their potential applications in many research fields. In this report, we demonstrate the synthesis of 1,8,13‐trisubstituted triptycenes via palladium‐catalyzed α‐selective bromination. The sulfide directing group was effective to facilitate the halogenation of the proximal three benzene rings.

A Tf2O-mediated intramolecular phospha-Friedel–Crafts-type reaction of secondary biarylphosphine oxides has been developed. The reaction is promoted simply by Tf2O to form the corresponding dibenzophospholes under metal-free conditions. The starting substrates are readily available and easy-to-handle phosphine oxides, and the regioselectivity is controlled by the innate electronic nature. Thus, this newly developed protocol can provide concise and complementary approach to the highly π-conjugated dibenzophospholes of potent interest in material chemistry.

A nondirected dehydrogenative direct alkenylation of simple aromatic compounds with alkenes under rhodium catalysis is described. The site-selectivity is dominantly dictated by the steric bulkiness around the targeted C–H bond. The reaction efficiency was largely contingent on the identity of copper(II) carboxylate as oxidant, and considerable improvement of the productivity was achieved by the addition of a sulfate salt.A nondirected dehydrogenative direct alkenylation of simple aromatic compounds with alkenes under rhodium catalysis is described. The site-selectivity is dominantly dictated by the steric bulkiness around the targeted C–H bond. The reaction efficiency is largely contingent on the identity of copper(II) carboxylate as oxidant, and considerable improvement of the productivity was achieved by the addition of a sulfate salt.