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Iridium‐on‐phosphorus‐doped porous organic polymers (POP−Ir) were developed by anchoring simple iridium onto the skeleton of porous organic polymers through coordination bonds. This POP−Ir catalyst, which was thoroughly characterized by means of EDS, SEM, TEM, XRD, XPS, and FT‐IR, revealed excellent catalytic activity for the reaction of diphenyl phosphinamide with benzyl alcohols through borrowing hydrogen strategy and acceptorless dehydrogenation with wide functional group tolerance. Moreover, this POP−Ir catalyst could be simply recovered and reused for at least five times without a significant loss of activity, and revealed considerable application prospects. The mechanism was investigated to further understand this POP−Ir catalytic system and transformations. Overall, the POP−Ir catalytic system has shown high activity and reusability in the borrowing hydrogen reaction between diphenyl phosphinamides and benzyl alcohols. [ABSTRACT FROM AUTHOR]

Abstract: The Rh-catalyzed asymmetric hydrogenation of β-substituted α,β-unsaturated phosphonates using (Sc ,Sp )-WalPhos as the chiral ligand is reported, in which a wide range of optically active β-substituted alkylphosphonates were obtained in good yields and with good to excellent enantioselectivities (86–98% ee). In contrast to the Rh/(Rc ,Sa )-FAPhos system previously reported by us, the present catalytic system shows a wider substrate scope, and can perform the hydrogenation under milder reaction conditions. [Copyright &y& Elsevier]

Abstract: The first Rh-catalyzed enantioselective hydrogenation of dimethyl 2-methyleneglutarate and its derivatives has been reported. For the hydrogenation of dimethyl 2-methyleneglutarate with a chiral ferrocene-based monodentate phosphoramidite ligand (FAPhos), good enantioselectivity (over 90% ee) with full conversions was achieved. In contrast, the hydrogenation of substrates bearing an aryl substituent at a methylene moiety proved to be more difficult, in which the best enantioselectivity of up to 81% ee was obtained by the use of a P-stereogenic BoPhoz-type ligand. [Copyright &y& Elsevier]

Abstract: A new family of chiral bis(1-ferrocenylethyl)amine-derived monodentate phosphoramidite ligands has been prepared and successfully applied in the Cu-catalyzed asymmetric 1,4-conjugate addition of diethylzinc to a variety of α,β-unsaturated compounds, in which up to 99% ee was obtained for nitroalkenes at −78°C and >98% ee for cyclohexenone at −30°C, comparable to or higher than those obtained with the most efficient monophosphoramidite ligands reported so far. [Copyright &y& Elsevier]

[Display omitted] • Iridium and copper supported on silicon dioxide. • Iridium –catalyzed reaction of tert -butanesulfinamide with benzyl alcohol. • Selective synthesis of unsaturated carbonyl compounds. High active ligand usually plays an important role during catalysis and synthesis chemistry. A new and efficient benzotriazole-pyridinyl-silane ligand (BPS) was designed, and the corresponding iridium and copper catalysts were synthesized and thoroughly characterized by means of EDS, TEM, and XPS. The resulting iridium composite revealed excellent catalytic activity for the reaction of tert-butanesulfinamide with benzyl alcohols, while copper catalyst could realize the synthesis of unsaturated carbonyl compounds through the reaction of benzyl alcohols with ketones. This provided an efficient method for selective synthesis of unsaturated carbonyl compounds from benzyl alcohols and ketones in high yields with good recovery performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Heterogeneous pyrazoly-pyridinyl-triazole Ru complexes on γAl 2 O 3. • High catalytic activity for deoxygenative homocoupling of 2-arylethanols. • The first example for deoxygenative homocoupling of 2-arylethanols by using a recyclable catalyst. A pyrazolyl-pyridinyl-triazole Ru complex was synthesized from unsymmetrical pyrazolyl-pyridinyl-triazole (PPT) skeleton ligand and characterized through X-ray crystallography. The corresponding heterogeneous pyrazolyl-pyridinyl-triazole Ru complexes on γ-Al 2 O 3 were characterized through SEM, TEM, XRD and XPS. Both homogeneous and heterogeneous Ru catalysts revealed high activity for deoxygenative homocoupling of 2-arylethanols. [ABSTRACT FROM AUTHOR]

Abstract: A series of chiral alkylphosphonates bearing β-stereogenic center were synthesized in good enantioselectivities (up to 95% ee) via the CuH-catalyzed asymmetric conjugate reduction of β-substituted α,β-unsaturated phosphonates under optimal conditions using Cu(OAc)2·H2O as the copper source, (R)-SEGPHOS as the ligand, PMHS as the siloxane, and t-BuOH as the additive. [Copyright &y& Elsevier]

Herein, we report an efficient and straightforward approach for the synthesis of N-alkylated aminoquinoline derivatives by recyclable Cd-containing coordination polymer-catalyzed reactions of aminoquinolines with primary alcohols via the borrowing hydrogen strategy. In this work, a new type of coordination polymer [Cd(CIA)(phen)2(H2O)]n was successfully designed and fabricated. The molecular structure was corroborated by single-crystal X-ray diffraction and fully characterized by PXRD, FT-IR, TGA, and XPS. Importantly, this polymer revealed high catalytic activity for the N-alkylation reaction of 2-aminoquinoline and 8-aminoquinoline with inexpensive and low-toxicity alcohols as alkylating agents in excellent yields up to 95%. Interestingly, the present synthetic protocol was successfully applied for the gram-level synthesis of several biologically active compounds. In addition, several control reactions were carried out to investigate the possible mechanisms of this transformation. Finally, recycling experiments indicated that the cadmium coordination polymer showed good recovery performance for borrowing hydrogen reactions. [ABSTRACT FROM AUTHOR]

An iridium complex based on the unsymmetrical pyrenyl‐thiophene‐benzothiazole ligand was synthesized, and the iridium complex was supported on reduced graphene oxide successfully. The developed iridium catalyst PTB‐Ir@rGO was characterized through SEM, TEM, XPS, EDS. Meanwhile, we found that this heterogeneous iridium catalyst had high catalytic activity in N‐alkylation of benzamide with alcohols via borrowing hydrogen strategy. Moreover, several control reactions and preliminary mechanism explorations were carried out to study this transformation. Finally, the recycling experiment showed that the catalyst could be reused at least five times without a significant decrease in catalytic activity. [ABSTRACT FROM AUTHOR]

A coordination polymer Ni-CIA has been designed, synthesized, and characterized via Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectrometry (XPS), energy-dispersive X-ray spectroscopy (EDS), and thermal gravimetric analysis (TGA). The resulting polymer reveals a slice layer stacked combination structure and good stability. Importantly, this polymer exhibited high catalytic activity for the synthesis of oxindole and quinoline derivatives via borrowing hydrogen and dehydrogenation reactions. Meanwhile, several control reactions were carried out to investigate the possible mechanisms of this transformation. Finally, the results of the recycling experiment indicate that the coordination polymer Ni-CIA could be recovered and reused at least five times. [ABSTRACT FROM AUTHOR]

A diversity of enantio-enriched β-branched phosphonates is obtained by Rh-catalyzed hydrogenation of α,β-unsaturated phosphonates in the presence of chiral Walphos ligand. [ABSTRACT FROM AUTHOR]

A microwave-assisted three-step sequence allows the synthesis of the title compounds (VI) as pharmaceutically interesting frameworks. [ABSTRACT FROM AUTHOR]

Porous copper and cobalt polymers were designed, synthesized, and characterized by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray photoelectron spectrometry (XPS), Fourier-transform infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD). The resulting copper/cobalt composites exhibited a much higher catalytic activity towards the borrowing hydrogen reactions of benzenesulfonamides with benzyl alcohols and carboxamides with alcohols than copper polymers. In addition, copper/cobalt composites could be easily recovered and reused at least six times. Mechanism investigations were conducted to study Cu/Co composites and these transformations. [ABSTRACT FROM AUTHOR]

The quest for highly active and efficient ligands in coordination polymer-based catalytic applications is paramount. The new porous cross-linked polymer manganese composites, which featured a benzimidazole-pyrimidine backbone, were designed, synthesized and fully characterized through several modern means. The resulting manganese composites revealed good catalytic activity in the selective synthesis of bisindolylmethane derivatives with high selectivity. Furthermore, the porous cross-linked polymer matrix composites displayed impressive recyclability, demonstrating their economic and environmental merits, with mechanistic studies shedding light on these transformative processes.The new porous cross-linked polymer manganese composites, which featured a benzimidazole-pyrimidine backbone. The resulting manganese composites revealed good catalytic activity in the selective synthesis of bisindolylmethane derivatives with high selectivity. Furthermore, the porous cross-linked polymer matrix composites displayed impressive recyclability, demonstrating their economic and environmental merits, with mechanistic studies shedding light on these transformative processes.Graphical Abstract: The quest for highly active and efficient ligands in coordination polymer-based catalytic applications is paramount. The new porous cross-linked polymer manganese composites, which featured a benzimidazole-pyrimidine backbone, were designed, synthesized and fully characterized through several modern means. The resulting manganese composites revealed good catalytic activity in the selective synthesis of bisindolylmethane derivatives with high selectivity. Furthermore, the porous cross-linked polymer matrix composites displayed impressive recyclability, demonstrating their economic and environmental merits, with mechanistic studies shedding light on these transformative processes.The new porous cross-linked polymer manganese composites, which featured a benzimidazole-pyrimidine backbone. The resulting manganese composites revealed good catalytic activity in the selective synthesis of bisindolylmethane derivatives with high selectivity. Furthermore, the porous cross-linked polymer matrix composites displayed impressive recyclability, demonstrating their economic and environmental merits, with mechanistic studies shedding light on these transformative processes. [ABSTRACT FROM AUTHOR]

Abstract: A copper-catalyzed asymmetric propargylic amination with a chiral ketimine P,N,N-ligand that proceeds via decarboxylation of propargyl carbamates has been developed. The reaction can be performed under the mild condition for a broad range of substrates, providing the corresponding propargylic amines in high yields and with up to 97% ee. This reaction represents a new and facile access to optically active propargylic amines. [Copyright &y& Elsevier]

Abstract: The asymmetric conjugate reduction of 3-aryl-4-phosphonobutenoates has been demonstrated which provides an enantioselective synthesis of optically active 3-aryl-4-phosphonobutyric acid esters. A wide range of 3-aryl-4-phosphonobutenoate derivates are reduced with high enantioselectivities (up to 94% ee) using an (S)-Segphos/Cu(OAc)2·H2O catalyst system (1 or 5mol%) in the presence of PMHS and t-BuOH. The reduction is influenced by the steric and electronic effects of the substrates. [Copyright &y& Elsevier]

Abstract: A series of new H8-BINOL-derived unsymmetrical hybrid ferrocenylphosphine-phosphoramidite ligands have been synthesized and successfully used in Rh-catalyzed asymmetric hydrogenations. The same or higher enantioselectivities (99.9% ee) were achieved in the hydrogenation of dimethyl itaconate and α-dehydroamino acid esters as those obtained with BINOL-derived analogues. However, slightly lower enantioselectivities (99.0% ee) were obtained in the hydrogenation of enamides. [Copyright &y& Elsevier]

Metal-free, base-free, biomimetic and chemoselective synthesis of 2,4,6-trisubstituted pyridines was developed under mild conditions for the first time. The heterogeneous biomimetic catalyst – recoverable Merrifield resin-supported quinone – was fully characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectrometry (XPS) and energy dispersive X-ray spectroscopy (EDX). This supported quinone catalyst exhibited excellent catalytic reactivity for chemoselective synthesis of 2,4,6-trisubstituted pyridines, providing an efficient and green method for the synthesis of pyridine derivatives under mild conditions. Mechanistic investigations were conducted to gain insights into the heterogeneous biomimetic catalyst as well as the resulting transformation. The successful capture of intermediates offered direct and clear evidence for the proposed mechanism. [ABSTRACT FROM AUTHOR]

The title reaction proceeds under mild conditions and is suitable for a broad range of substrates providing optically active propargylic amines in high yields with high enantioselectivities. [ABSTRACT FROM AUTHOR]

A diagram is presented which explains the molecular structure 1,2-disulfane and 3,3,5,5-tetrabenzyl-1,2,4-trithiol chemical synthesis.

Abstract: A series of chiral ferrocene-based phosphine–phosphoramidite ligands (PPFAPhos) have been employed in the Ag(I)-catalyzed asymmetric [3+2] cycloaddition of azomethine ylides with dimethyl maleate. The results showed that the ligand with a stereogenic P-center in the phosphino moiety displayed the best diastereo- and enantioselectivities, in which up to 99% enantiomeric excesses and 99/1 endo/exo selectivities have been achieved. [Copyright &y& Elsevier]

Abstract: Methyl 3-hydroxy-2-methylpropionate, known as the Roche ester, was prepared with high enantioselectivity (up to 96.7% ee) via the Rh-catalyzed asymmetric hydrogenation of methyl 2-hydroxymethylacrylate with a chiral 1,2,3,4-tetrahydro-1-naphthylamine-derived phosphine-phosphoramidite ligand (THNAPhos 5a) even at a low catalyst loading (0.1mol%). An investigation on the substrate scope revealed that the ester group present in the substrate has a significant effect on the enantioselectivity, and the substrate with the bulkier ester group tended to give lower enantioselectivity. [Copyright &y& Elsevier]

Abstract: A new chiral phosphine-phosphoramidite ligand (S)-HY-Phos 1 has been prepared from 1-naphthylamine via a two-step transformation, and successfully applied in the Rh-catalyzed asymmetric hydrogenation of various functionalized olefins, including α-(acetamido)cinnamates, enamides and α-enol ester phosphonates, in which up to 98% ee, 99% ee and 99% ee were achieved, respectively. [Copyright &y& Elsevier]

Abstract: A series of ferrocene-based phosphine–triazine ligands were successfully employed in the Pd-catalyzed Suzuki–Miyaura cross-coupling reaction of aryl chlorides with arylboronic acids, with ligand 1b was demonstrated to be the most effective one. Under optimized reaction conditions, the catalytic system displayed a remarkable tolerance towards electron-donating substituents and electron-withdrawing substituents. [Copyright &y& Elsevier]

Abstract: A series of novel chiral phosphine–imine ligands have been prepared by a two-step transformation from chiral α-phenylethylamine. The resulting chiral ligands were found to be effective for the palladium-catalyzed asymmetric allylic alkylation of 1,3-diphenylprop-2-en-1-yl pivalate with dimethyl malonate, in which up to 94% ee and 99% conversions were obtained. The results demonstrate that the chirality resided on the chelate ring of P–Pd–N complex is more effective for the transfer of the stereochemical information by comparison with the result obtained by Hashimoto and coworkers’ phosphine–imine ligand, in which the chirality lay in the outside of P–Pd–N chelate ring. The effect of solvent, base and substitutent in phosphine–imine ligand on this catalytic reaction is also described. [Copyright &y& Elsevier]