6048-06-2Relevant academic research and scientific papers
Palladium-Catalyzed Allyl-Allyl Reductive Coupling of Allylamines or Allylic Alcohols with H2as Sole Reductant
Zhou, Xibing,Zhang, Guoying,Huang, Renbin,Huang, Hanmin
supporting information, p. 365 - 369 (2021/01/26)
Catalytic carbon-carbon bond formation building on reductive coupling is a powerful method for the preparation of organic compounds. The identification of environmentally benign reductants is key for establishing an efficient reductive coupling reaction. Herein an efficient strategy enabling H2 as the sole reductant for the palladium-catalyzed allyl-allyl reductive coupling reaction is described. A wide range of allylamines and allylic alcohols as well as allylic ethers proceed smoothly to deliver the C-C coupling products under 1 atm of H2. Kinetic studies suggested that the dinuclear palladium species was involved in the catalytic cycle.
Intramolecular Sakurai Allylation of Geminal Bis(silyl) Enamide with Indolenine. A Diastereoselective Cyclization to Form Functionalized Hexahydropyrido[3,4- b]Indole
Chen, Yi,Gao, Lu,Song, Xuanyi,Song, Zhenlei
supporting information, p. 124 - 128 (2021/01/13)
A fluoride-promoted intramolecular Sakurai allylation of geminal bis(silyl) enamide with indolenine has been developed. The reaction facilitates an efficient cyclization to give hexahydropyrido[3,4-b]indoles in good yields with high diastereoselectivity. The resulted cis, trans-stereochemistry further enables the ring-closing metathesis (RCM) reaction of two alkene moieties, giving a tetracyclic N-hetereocycle widely found as the core structure in akuammiline alkaloids.
Synthesis method of isochroman compound
-
Paragraph 0046; 0049; 0073; 0076, (2021/05/15)
The invention discloses a synthesis method of an isochroman compound, which comprises the following steps of adding dichloromethane and phosphorus tribromide into 3, 4, 5-trimethoxy benzyl alcohol, and reacting to obtain 1-bromomethyl-3, 4, 5-trimethoxy benzene, adding tetrahydrofuran, cinnamyl alcohol, sodium hydride and 1-bromomethyl-3, 4, 5-trimethoxybenzene into a reactor, and reacting to obtain 1-[(cinnamyl oxy)methyl]-3, 4, 5-trimethoxybenzene, adding cyanuric acid into a reactor containing a potassium hydroxide aqueous solution to react, dropwise adding a silver nitrate aqueous solution, and reacting to obtain silver isocyanurate, adding silver isocyanurate, phenyl selenium bromide and anhydrous dichloromethane into a reactor, and reacting to obtain N, N, N-triphenyl seleno isocyanurate, reacting N, N, N-triphenyl seleno isocyanurate, dichloromethane, boron trifluoride diethyl etherate and a 1-[(cinnamyl oxy)methyl]-3, 4, 5-trimethoxybenzene compound to obtain a target product. The method is simple in reaction operation, mild in reaction condition, relatively high in yield and environment-friendly.
Palladium Immobilized on 2,2′-Dipyridyl-Based Hypercrosslinked Polymers as a Heterogeneous Catalyst for Suzuki–Miyaura Reaction and Heck Reaction
Liu, Cijie,Xu, Wei,Xiang, Dexuan,Luo, Qionglin,Zeng, Shunqin,Zheng, Lijuan,Tan, Yujie,Ouyang, Yuejun,Lin, Hongwei
, p. 2558 - 2565 (2020/03/23)
Abstract: 2,2′-Bipyridine was successfully integrated into the skeleton of hypercrosslinked polymers networks (HCPs-bipy) via Friedel–Crafts reaction and Scholl coupling reaction, and PdCl2 was locked in this network polymers by coordination with pyridine motif. The preparation of HCPs-bipy has the advantages of low cost, mild conditions, easy separation and high yield. FT-IR, TGA, N2 sorption, ICP, XPS, SEM, EDX and TEM was employed to characterize the structure and composition of the heterogeneous catalysts. The result indicates that HCPs-bipy-Pd possess high specific surface areas, large microporous volume, thermal stability, and highly dispersion of palladium species. HCPs-bipy-Pd can be applied in Suzuki–Miyaura reactions and Heck reactions as robust heterogeneous catalyst to afford high yield. The reusability test demonstrates that HCPs-bipy-Pd could be recovered and reused for at least five times without losing catalytic activity. Graphic Abstract: [Figure not available: see fulltext.].
Palladium Ion Catalysed Oxidative C–C Bond Formation Reactions in Arylboronic Acid: Application of Cordierite Monolith Coated Catalyst
Bhat, Shrikanth K.,Prasanna,Dasappa, Jagadeesh Prasad,Hegde
, p. 2911 - 2927 (2020/03/31)
Abstract: Catalytic efficiency of palladium ion substituted in TiO2, Ti0.97Pd0.03O1.97 is successfully exploited for the oxidative homocoupling of arylboronic acid and oxidative Heck coupling reactions between arylboronic acid and olefins. The reaction protocol provides direct approach to synthesize biphenyls and cinnamates from moderate to good yield with good functional group tolerance. As a result, 11 symmetrical biaryls and 14 cinnamates were synthesized from readily available arylboronic acids. Ti0.97Pd0.03O1.97 powder catalyst is synthesized by solution combustion method and characterized by powder X-ray diffraction. The C–C bond formation reactions were carried out by catalyst cartridge method using Ti0.97Pd0.03O1.97 catalyst coated cordierite monolith. Coating of the catalyst on a cordierite monolith enhanced the applicability of the catalyst and made handling and recycling of the catalyst very easy. Catalyst was recovered and recycled for eight times in both homocoupling and oxidative Heck coupling reactions. The turnover number for both the reactions found to be 443 and 424, respectively. Graphic Abstract: [Figure not available: see fulltext.].
Synergistic Relay Reactions To Achieve Redox-Neutral α-Alkylations of Olefinic Alcohols with Ruthenium(II) Catalysis
Kan, Jian,Li, Chao-Jun,Li, Chen-Chen,Li, Jianbin,Lv, Leiyang,Qiu, Zihang
supporting information, p. 4544 - 4549 (2020/02/04)
Herein, we report a ruthenium-catalyzed redox-neutral α-alkylation of unsaturated alcohols based on a synergistic relay process involving olefin isomerization (chain walking) and umpolung hydrazone addition, which takes advantage of the interaction between the two rather inefficient individual reaction steps to enable an efficient overall process. This transformation shows the compatibility of hydrazone-type “carbanions” and active protons in a one-pot reaction, and at the same time achieves the first Grignard-type nucleophilic addition using olefinic alcohols as latent carbonyl groups, providing a higher yield of the corresponding secondary alcohol than the classical hydrazone addition to aldehydes does. A broad scope of unsaturated alcohols and hydrazones, including some complex structures, can be successfully employed in this reaction, which shows the versatility of this approach and its suitability as an alternative, efficient means for the generation of secondary and tertiary alcohols.
Boron-Catalyzed C?C Functionalization of Allyl Alcohols
Rao, Santhosh,Kapanaiah, Raja,Prabhu, Kandikere Ramaiah
supporting information, (2019/02/14)
Tris(pentafluorophenyl)borane-catalyzed C?C bond functionalization of arylallyl alcohols using donor-acceptor carbenes is presented. The allylic hydroxyl group is found to assist the product formation by neighboring group participation providing a clue towards mechanistic understanding. This method can also be employed to effect homologation of allyl alcohols to homoallyl alcohols. Overall, this metal-free transformation presents a novel disconnection strategy towards carbon-carbon bond scission and formation. (Figure presented.).
Synthesis of Allylsilanes via Nickel-Catalyzed Cross-Coupling of Silicon Nucleophiles with Allyl Alcohols
Yang, Bo,Wang, Zhong-Xia
supporting information, p. 7965 - 7969 (2019/10/19)
NiCl2(PMe3)2-catalyzed reaction of allyl alcohols with silylzinc reagents, including PhMe2SiZnCl, Ph2MeSiZnCl, and Ph3SiZnCl, was performed, achieving allylsilanes in high yields. Aryl- and heteroaryl-substituted allyl alcohols, (E)-3-arylprop-2-en-1-ols, 1-aryl-prop-2-en-1-ols, and (E)-1-phenylpent-1-en-3-ol can be employed in the transformation. A range of functional groups as well as heteroaryl groups were tolerated. Reaction exhibited high regioselectivity and E/Z-selectivity when 1- or 3-aryl-substituted allyl alcohols were used as the substrates. Reaction of chiral allyl alcohol, (S,E)-1-phenylpent-1-en-3-ol, yielded a configuration-inversion product (R,E)-dimethyl(phenyl)(1-phenylpent-1-en-3-yl)silane.
Boron-Templated Dimerization of Allylic Alcohols to Form Protected 1,3-Diols via Acid Catalysis
Nazari, S. Hadi,Forson, Kelton G.,Martinez, Erin E.,Hansen, Nicholas J.,Gassaway, Kyle J.,Lyons, Nathan M.,Kenney, Karissa C.,Valdivia-Berroeta, Gabriel A.,Smith, Stacey J.,Michaelis, David J.
supporting information, p. 9589 - 9593 (2019/12/02)
We report an unprecedented boron-templated dimerization of allylic alcohols that generates a 1,3-diol product with two stereogenic centers in high yield and diastereoselectivity. This acid-catalyzed reaction is achieved via in situ formation of a boronic ester intermediate that facilitates selective cyclization and formation of a cyclic boronic ester product. High yields are observed with a variety of allylic alcohols, and mechanistic studies confirm the role of boron as a template for the reaction.
Arene Trifunctionalization with Highly Fused Ring Systems through a Domino Aryne Nucleophilic and Diels–Alder Cascade
He, Jia,Jia, Zizi,Tan, Hongcheng,Luo, Xiaohua,Qiu, Dachuan,Shi, Jiarong,Xu, Hai,Li, Yang
supporting information, p. 18513 - 18518 (2019/11/19)
A convenient and efficient domino aryne process was developed under transition-metal-free conditions to generate a range of tetra- and pentacyclic ring systems. This transformation was realized via a 1,2-benzdiyne through a nucleophilic and Diels–Alder reaction cascade using styrene as the diene moiety. Three new chemical bonds, namely one C?N and two C?C bonds, and two benzofused rings could be constructed concomitantly, which was made possible by distinct chemoselective control at both the 1,2-aryne and 2,3-aryne stages. Moreover, in-depth studies were carried out on the domino aryne precursors and controlling the diastereoselectivity.
