Tag: M.W=600-700

Hirata, Shuzo; Hara, Hyuman; Bhattacharjee, Indranil published the artcile< Phosphorescence Quenching of Heavy-Atom-Free Dopant Chromophores Triggered by Thermally Activated Triplet Exciton Diffusion of a Conjugated Crystalline Host>, Formula: C44H40P2, the main research area is phosphorescence quenching heavy atom dopant chromophore thermally activated triplet.

Persistent room-temperature phosphorescence (pRTP) from aggregated mol. crystalline materials is important for stable high-resolution afterglow imaging. However, an unclear understanding concerning the deactivation mechanism from the lowest triplet excited state (T1) precludes the development of highly efficient pRTP. Here, we report the reasons for the presence and absence of pRTP from a heavy-atom-free conjugated dopant in heavy-atom-free conjugated mol. crystals. N,N-di(9H-fluoren-2-yl)phenanthrene-3-amine (DFAP) was sep. doped into fluorene crystals and (S)-2,2′-bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthalene ((S)-H8-BINAP) crystals. DFAP doped in fluorene crystals with stronger intermol. interactions did not generate RTP, while DFAP doped in (S)-H8-BINAP crystals with weaker intermol. interactions showed strong pRTP. The pRTP of DFAP doped in (S)-H8-BINAP crystals is explained by the deep confinement of the T1 of DFAP in the (S)-H8-BINAP crystals with a large T1 energy. The absence of RTP from DFAP doped in fluorene crystals is explained by the temperature dependence of phosphorescence and quantum calculations, which suggest that deactivation is mainly caused by quenching after diffusion of triplet excitons of the host crystals. The temperature dependence of the triplet-triplet annihilation-based delayed fluorescence of the fluorene crystalline host confirms that the triplet diffusion of the fluorene crystalline host deactivates the triplet excitons of DFAP.

Journal of Physical Chemistry C published new progress about Chromophores. 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Formula: C44H40P2.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Pradal, Alexandre; Chao, Chung-Meng; Vitale, Maxime R.; Toullec, Patrick Y.; Michelet, Veronique published the artcile< Asymmetric Au-catalyzed domino cyclization/nucleophile addition reactions of enynes in the presence of water, methanol and electron-rich aromatic derivatives>, Name: (S)-(+)-4,12-Bis(di(3,5-xylyl)phosphino)-[2.2]-paracyclophane, the main research area is asym gold catalyst cyclization nucleophilic addition enyne.

An efficient Au(I) catalytic system is described for the asym. domino cyclization/functionalization reactions of functionalized 1,6-enynes in the presence of an external nucleophile. The use of (R)-4-MeO-3,5-(t-Bu)2-MeOBIPHEP ligand associated with gold led to clean rearrangements implying the formal addition of an oxygen or carbon nucleophile to an alkene followed by a cyclization process. The enantiomeric excesses were highly dependent on the substrate/nucleophile combination. Very good enantiomeric excesses up to 98% were obtained in the case of substrates bearing larger groups (hindered diesters and disulfones) and in the case of hindered carbon nucleophiles.

Tetrahedron published new progress about Addition reaction catalysts, stereoselective. 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, Name: (S)-(+)-4,12-Bis(di(3,5-xylyl)phosphino)-[2.2]-paracyclophane.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Tsuchikama, Kyoji; Yoshinami, Yusuke; Shibata, Takanori published the artcile< Rhodium-complex-catalyzed [2+2+2] cycloaddition of diynes and carbonyl compounds>, Product Details of C44H40P2, the main research area is diyne carbonyl stereoselective cycloaddition rhodium BINAP catalyst; hydropyran stereoselective preparation electrocyclic ring opening; cyclopentene stereoselective preparation; hydropyrrole stereoselective preparation; hydrofuran stereoselective preparation.

A Rh-BINAP complex was used to catalyze the hetero-[2+2+2] cycloaddition of sym. 1,6-diynes and carbonyl moiety of keto esters, a diketone, and an aldehyde to give bicyclic α-pyrans, which were readily transformed into monocyclic compounds via the following electrocyclic ring opening. In the reaction of an unsym. 1,6-diyne and a 1,7-diyne, α-pyrans with a quaternary carbon stereocenter were obtained in moderate to excellent ee using a chiral rhodium catalyst.

Synlett published new progress about Alkadiynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Product Details of C44H40P2.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Tanaka, Ken; Takahashi, Yoshihiro; Suda, Takeshi; Hirano, Masao published the artcile< Synthesis of enantioenriched N-aryl-2-pyridones with chiral C-N axes by rhodium-catalyzed [2+2+2] cycloaddition of alkynes with isocyanates>, Electric Literature of 139139-93-8, the main research area is alkadiyne phenyl isocyanate stereoselective cycloaddition rhodium catalyst; pyridone stereoselective preparation.

Enantioenriched N-aryl-2-pyridones with axially chiral C-N bonds were prepared by a cationic rhodium(I)-BINAP or tol-BINAP-catalyzed enantioselective [2+2+2] cycloaddition of alkadiynes with ortho-substituted Ph isocyanates.

Synlett published new progress about Alkadiynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Electric Literature of 139139-93-8.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Tanaka, Ken; Nishida, Goushi; Ogino, Masakazu; Hirano, Masao; Noguchi, Keiichi published the artcile< Enantioselective synthesis of axially chiral biaryls through rhodium-catalyzed complete intermolecular cross-cyclotrimerization of internal alkynes>, Electric Literature of 139139-93-8, the main research area is alkyne acetylenedicarboxylate cross cyclotrimerization rhodium BINAP; biaryl asym preparation; benzenetetracarboxylate preparation.

A cationic rhodium(I)/H8-BINAP complex-catalyzed complete intermol. cross-cyclotrimerization of internal alkynes with dialkyl acetylenedicarboxylates was developed. This reaction was successfully applied to enantioselective synthesis of axially chiral biaryls, e.g., I, utilizing internal alkynes bearing ortho-substituted Ph and acetoxymethyl in each terminal position. The axial chirality was constructed at the formation of benzene rings with high enantioselectivity.

Organic Letters published new progress about Alkynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Electric Literature of 139139-93-8.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Masutomi, Koji; Sugiyama, Haruki; Uekusa, Hidehiro; Shibata, Yu; Tanaka, Ken published the artcile< Asymmetric Synthesis of Protected Cyclohexenylamines and Cyclohexenols by Rhodium-Catalyzed [2+2+2] Cycloaddition>, HPLC of Formula: 139139-86-9, the main research area is protected cyclohexenylamine cyclohexenol preparation rhodium catalyst cycloaddition; asymmetric catalysis; cycloadditions; enamides; reaction mechanisms; rhodium.

Cationic rhodium(I)/axially chiral biaryl bis(phosphine) complexes catalyze the asym. [2+2+2] cycloaddition of 1,6-enynes with electron-rich functionalized alkenes, enamides, and vinyl carboxylates, to produce the corresponding protected cyclohexenylamines and cyclohexenols. Regioselectivity depends on structures of substrates. The present cycloaddition was successfully applied to the enantioselective total synthesis of (-)-porosadienone by using the amide moiety as a leaving group.

Angewandte Chemie, International Edition published new progress about [2+2+2] Cycloaddition reaction. 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, HPLC of Formula: 139139-86-9.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Tanaka, Ken; Shirasaka, Kaori published the artcile< Highly Chemo- and Regioselective Intermolecular Cyclotrimerization of Alkynes Catalyzed by Cationic Rhodium(I)/Modified BINAP Complexes>, Category: chiral-phosphine-ligands, the main research area is chemoselective regioselective intermol cocyclotrimerization alkyne cationic rhodium BINAP complex; diethyl acetylenedicarboxylate chemoselective regioselective intermol cocyclotrimerization rhodium BINAP complex.

Cationic rhodium(I)/modified BINAP complexes are effective catalysts for highly regioselective intermol. cyclotrimerization of terminal alkynes and highly chemo- and regioselective intermol. cocyclotrimerization of di-Et acetylenedicarboxylate (DEAD) and terminal alkynes. It is a noteworthy example of intermol. cocyclotrimerization of two different alkynes in terms of catalytic activity, chemo- and regioselectivity, scope of substrates, and ease of operation. The wide applicability of this new cocyclotrimerization procedure is demonstrated in the one-step synthesis of [6]metacyclophane.

Organic Letters published new progress about Alkynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Category: chiral-phosphine-ligands.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Murayama, Koichi; Shibata, Yu; Sugiyama, Haruki; Uekusa, Hidehiro; Tanaka, Ken published the artcile< Synthesis, structure, and photophysical/chiroptical properties of benzopicene-based π-conjugated molecules>, Electric Literature of 139139-93-8, the main research area is benzopicene pi conjugated hydrocarbon ladder helical structure preparation cycloaddition; cycloaddition dialkynyl binaphthalene preparation benzopicene ladder helical polycycle; crystal structure helical benzopicene fluorenone ketone.

The convenient synthesis of substituted benzopicenes and azabenzopicenes I (X = C, N; R1, R2 = H, CO2Et, alkyl, CH2CH) has been achieved by the cationic rhodium(I)/H8-BINAP or BINAP complex-catalyzed [2+2+2] cycloaddition of 1,1′-dialkynyl-2,2′-binaphthalene under mild conditions. This method was applied to the synthesis of benzopicene-based long ladder (II, R3 = C12H25) and helical (III, R4 = Ph, Bu; Y2 = O, 9-fluorenylidene) mols. The x-ray crystal structure anal. revealed that the benzopicene-based helical mol. is highly distorted and the average distance of overlapped rings is markedly shorter than that in the triphenylene-based helical mol. Photophys. and chiroptical properties of these benzopicene and azabenzopicene derivatives have also been examined With respect to photophys. properties, substituted benzopicenes and azabenzopicenes showed red shifts of absorption and emission maxima compared with the corresponding triphenylenes and azatriphenylenes. With respect to chiroptical properties, the CPL spectra of the benzopicene-based helical mol. showed two opposite peaks, and thus the value of the CPL was smaller than that of the triphenylene-based helical mol. presumably due to the presence of two chiral fluorophores.

Journal of Organic Chemistry published new progress about [2+2+2] Cycloaddition reaction. 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Electric Literature of 139139-93-8.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Tanaka, Ken; Sagae, Hiromi; Toyoda, Kazuki; Noguchi, Keiichi; Hirano, Masao published the artcile< Enantioselective Synthesis of Planar-Chiral Metacyclophanes through Rhodium-Catalyzed Alkyne Cyclotrimerization>, Safety of (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, the main research area is metacyclophane asym synthesis; alkyne stereoselective cyclotrimerization rhodium catalyst.

The first catalytic enantioselective synthesis of planar-chiral metacyclophanes via cationic rhodium(I)/(R)-H8-BINAP complex-catalyzed alkyne cyclotrimerization is described. This reaction represents a versatile new method for the preparation of planar-chiral [7]-[10]metacyclophanes.

Journal of the American Chemical Society published new progress about Alkadiynes Role: RCT (Reactant), RACT (Reactant or Reagent). 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Safety of (R)-2,2′-Bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Bandini, Marco; Gualandi, Andrea; Monari, Magda; Romaniello, Alessandro; Savoia, Diego; Tragni, Michele published the artcile< Allylic alcohols: Valuable synthetic equivalents of non-activated alkenes in gold-catalyzed enantioselective alkylation of indoles>, Reference of 325168-88-5, the main research area is allylic alc tethered indole derivative preparation; chiral ligand gold catalyzed intramol allylic alkylation indole derivative; tetrahydrocarbazole derivative stereoselective preparation; tetrahydrocarboline derivative stereoselective preparation.

The recent booming of gold catalysis has demonstrated that unprecedented transformations can be realized in a highly selective manner. Moreover, due to the growing availability of chiral organic ligands, gold-catalysis can be considered as one of most dynamic hot spots in asym. synthesis. However, in this context, the use of non-activated olefinic C-C double bonds is still largely unexplored due to the intrinsic inertness of C=C (respect to allenes and alkynes) in taking part in nucleophilic additions assisted by π-electrophilic activations. Allylic alcs. have been demonstrated to be feasible “”surrogates”” of non-activated alkenes for the enantioselective allylic alkylation of indoles catalyzed by chiral gold(I) complexes. In this investigation, a full account addressing efficiency and substrate scope of such a process is presented. The products, tetrahydrocarbazoles or tetrahydro-β-carbolines, are obtained in moderate to good yields and 40-86% ee from the corresponding Z-allylic alc.-containing substrates, while the E isomers are unreactive.

Journal of Organometallic Chemistry published new progress about Allylic alcohols Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, Reference of 325168-88-5.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate