Article
Chemistry, Organic
Toshitaka Okamura, Kenta Koyamada, Junichiro Kanazawa, Kazunori Miyamoto, Yoshiharu Iwabuchi, Masanobu Uchiyama, Naoki Kanoh
Summary: This study presents a method for synthesizing difluoropropargyl vinyl ethers from ketones and aldehydes using difluoropropargyl bromide dicobalt complexes, which are then used for the synthesis of various fluorinated compounds under different conditions.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Daniels Posevins, Aitor Bermejo-Lopez, Jan-E. Backvall
Summary: An iron-catalyzed cross-coupling reaction of propargyl ethers with Grignard reagents was disclosed, allowing for efficient chirality transfer and preparation of various fluoroalkyl allenes. Additionally, an iron-catalyzed cross-coupling of Grignard reagents with alpha-alkynyl oxetanes and tetrahydrofurans was demonstrated as a straightforward approach towards fully substituted beta- or gamma-allenols.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Chada Raji Reddy, Ejjirotu Srinivasu, Puppala Sathish, Muppidi Subbarao, Ramachandra Reddy Donthiri
Summary: The arylation of 2-carbonyl-3-propargyl indoles with boronic acids under sequential palladium/triflic acid catalysis provides di- and triaryl carbazoles in one pot, showing a good substrate scope and decent yields.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Applied
Camille Van Wesemael, Nicolas Brach, Mihaela Gulea, Gaelle Blond
Summary: A series of 3-allenyl benzo[b]thiophenes were synthesized through a gold(I)-catalyzed domino reaction. The process involves a 5-endo-dig cyclization with C S bond formation and consecutive S-to-C propargyl migration via [3,3]-sigmatropic Claisen rearrangement. Various fused O-heterocycles can be obtained from a substrate bearing a 3-butynol moiety via intramolecular hydroalkoxylation. The gold-mediated 1,3-migration involving allenyl to propargyl rearrangement is also described.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Multidisciplinary Sciences
Lei Wang, Chuiyi Lin, Qinglei Chong, Zhihan Zhang, Fanke Meng
Summary: Catalytic enantioselective introduction of a propargyl group is an important carbon-carbon forming reaction, but only a few Cu- or Ni-catalyzed protocols with limited reaction modes are known. Here, the authors describe a photoredox/cobalt-catalyzed propargyl addition to aldehydes via propargyl radicals which enables the construction of a broad scope of homopropargyl alcohols that are otherwise difficult to access. Mechanistic studies and DFT calculations provide evidence for the involvement of propargyl radicals, the origin of the stereoconvergent process, and the stereochemical models.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Stephen Collins, Joshua D. Sieber
Summary: In this study, we present an improved system for the Cu-catalyzed enantioselective reductive coupling of ketones and allenamides by optimizing the allenamide to prevent on-cycle rearrangement. High enantioselectivities were achieved for various ketones. Unlike cyclic allenamides, which favor the syn-form, the acyclic allenamides described in this work selectively generated anti-diastereomers. A rationalization for this change in diastereoselectivity is also provided.
Article
Chemistry, Organic
Samantha L. Gargaro, Raphael K. Klake, Joshua D. Sieber
Summary: Here, we describe the development of a Cu-catalyzed enantioselective borylative aminoallylation reaction using a N-substituted alleneto access boryl-substituted 1,2-aminoalcohol synthons for generating chiral heteroatom-rich organic compounds. The reaction provides easy access to various substitution patterns of chiral 1,2-aminoalcohol products with high diastereo- and enantioselectivity from readily available starting materials.
Article
Chemistry, Organic
Raphael K. Klake, Mytia D. Edwards, Joshua D. Sieber
Summary: A new catalytic enantioselective addition method utilizing copper-catalyzed reductive coupling to add N-substituted allyl equivalents to ketones has been developed, accessing important chiral 1,2-aminoalcohol synthons with high levels of regio-, diastereo-, and enantioselectivity. Factors affecting enantioinduction are discussed, including the identification of a reversible ketone allylation step previously unreported in copper-catalyzed reductive coupling.
Article
Chemistry, Organic
Dong-Ping Wu, Wei Ou, Pei-Qiang Huang
Summary: This study describes the catalytic reductive condensation reactions between tertiary amides and active methylene compounds, leading to multifunctionalized non-N-containing products. The reactions proceed through a sequential process involving iridium-catalyzed hydrosilylation of the amides followed by acid-mediated condensation with the active methylene compounds. This scalable method demonstrates a broad scope and remarkable chemoselectivity for the amide group in the presence of various sensitive or even more reactive functionalities such as ester, cyano, nitro, silyl dienol ether, and ketone.
Article
Chemistry, Multidisciplinary
David Elorriaga, Fernando Carrillo-Hermosilla, Blanca Parra-Cadenas, Antonio Antinolo, Joaquin Garcia-Alvarez
Summary: This study investigated the synthesis of highly selective asymmetric tertiary alcohols under the absence of external organic solvents. It was found that the reaction can be carried out at room temperature and under air/moisture, without the need for a protecting atmosphere. The results showed high chemoselectivity and the possibility of scaling up the protocol.
Article
Chemistry, Multidisciplinary
Mitsuhiro Yoshimatsu, Hiroki Goto, Rintaro Saito, Kodai Iguchi, Manoka Kikuchi, Hiroaki Wasada, Yoshiharu Sawada
Summary: Dehydration is a promising process that can contribute to building a modern and sustainable society. Breakthrough advances in the dehydrative S(N)1 reaction can be achieved using new cationic indium catalysts. This reaction enables the direct formation of carbon-carbon bonds under mild, open-air conditions and is tolerant of a wide range of functional groups. Additionally, it allows the synthesis of previously inaccessible compounds and offers a more eco-friendly and efficient alternative to conventional methods.
COMMUNICATIONS CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Justin S. Marcum, Simon J. Meek
Summary: The enantioselective synthesis of bis-homoallylic alcohols through nickel-catalyzed three-component fragment couplings of simple aldehydes, dienes, and aryl organoborons is described. The reactions proceed through diene dicarbofunctionalization, which results in the formation of two C-C bonds and two stereogenic centers. These transformations are promoted by a 5.0 mol % loading of a readily accessible chiral phosphine-nickel complex and yield products with high stereoselectivity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Inorganic & Nuclear
Guomei He, Jiangxi Chen, Herman Ho-Yung Sung, Ian Duncan Williams, Guochen Jia
Summary: The reactions of rhenium polyhydride with propargyl alcohols in the presence of HCl produce gamma-hydroxycarbyne, vinylcarbyne and eta(2)-vinyl complexes, with the type and quantity of products depending on the substituents of the propargyl alcohols. The selectivity for the products is influenced by the steric and electronic effects of the substituents, favoring eta(2)-vinyl complexes with sterically less demanding substituents and gamma-hydroxycarbyne complexes with electron withdrawing substituents.
INORGANICA CHIMICA ACTA
(2021)
Article
Chemistry, Physical
Fangzhi Hu, Xinyao Li, Zhanshuai Ding, Liang Wang, Chunyan Ge, Lubin Xu, Shuai-Shuai Li
Summary: A synthetic strategy for the divergent synthesis of various types of [3,4]-fused oxindoles was developed, utilizing different nucleophiles to construct a wide range of organic compounds. The method shows potential applications in the field of alkaloids and organic synthesis.
Article
Chemistry, Organic
Liam M. Joyce, Stephen A. Moggach, Christopher J. T. Hyland, Stephen G. Pyne, Scott G. Stewart
Summary: A nickel-catalyzed tetradehydro-Diels-Alder reaction of (E)-3-ene-1,8-diynes has been developed for the synthesis of isoindolines, dihydroisobenzofurans, and tetrahydroisoquinolines. Air-stable nickel catalysts, including novel nickel(0)-phosphite catalysts, were employed in this study. Additionally, the mechanism of trapping nickellacycle intermediates with pinacolborane to yield vinyl boronates was discussed to gain insights into the initial cycloisomerization process.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
