Elsevier eBooks, Journal Year: 2024, Volume and Issue: unknown
Published: Jan. 1, 2024
Language: Английский
Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(33), P. 23476 - 23486
Published: Aug. 7, 2024
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Citations
1
Current Organic Synthesis, Journal Year: 2024, Volume and Issue: 21(7), P. 889 - 902
Published: Jan. 4, 2024
Abstract: Allenamides are special allenes, and the unique reactivity, selectivity (both stereoselective regionally selective) stability of allenamides have been widely studied. In this review, development free radical transformation over last few years will be summarized. This review discusses in detail three parts: intermolecular addition to C- X (X = N, S, O, Se) bonds, metal salt mediated cyclization allenamides, photocatalytic allenamides. addition, reasonable details mechanisms provided for vast majority these transformations.
Language: Английский
Citations
0
Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(23)
Published: April 3, 2024
Abstract Catalytic methods allowing for the reliable prediction and control of diverse regioselectivity along with enantioselectivity to access different regio‐ enantiomers by switching least reaction parameters are one most attractive ways in organic synthesis, which provide enantioenriched architectures from identical starting materials. Herein, a Co‐catalyzed regiodivergent enantioselective reductive hydroalkylation 1,3‐dienes aldehydes has been achieved, furnishing homoallylic alcohol good levels enantioselectivity. The features switch tuned selection proton source. use an acid as source provided asymmetric 1,2‐hydroalkylation products under conditions, yet 4,3‐hydroalkylation were obtained silane hydride This catalytic protocol allows alcohols two continuous saturated carbon centers regio‐, diastereo‐,
Language: Английский
Citations
0
Angewandte Chemie, Journal Year: 2024, Volume and Issue: unknown
Published: May 31, 2024
Abstract Catalytic enantioselective alkenylation of aldehydes with easily accessible alkenyl halides promoted by a chiral cobalt complex derived from newly developed tridentate bisoxazolinephosphine is presented. Such processes represent an unprecedented reaction pathway for catalysis and general approach that enable rapid construction highly diversified enantioenriched allylic alcohols containing 1,1‐, 1,2‐disubstituted trisubstituted alkene as well axial stereogenicity in up to 99 % yield : 1 er without the need preformation alkenyl–metal reagents. DFT calculations revealed origin enantioselectivity.
Language: Английский
Citations
0
Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(37)
Published: June 25, 2024
Abstract Chiral allylic alcohols are highly prized in synthetic chemistry due to their versatile reactivity stemming from both alkenyl and hydroxyl functionalities. While the Nozaki–Hiyama–Kishi (NHK) reaction is a widely used method for synthesis of alcohols, it suffers drawbacks such as use toxic chromium salts, high amounts metal reductants, poor enantiocontrol. To address these limitations, we present novel approach involving metallaphotoredox‐catalyzed asymmetric NHK production chiral alcohols. This marries (pseudo)halides with aldehydes, leveraging synergistic blend nickel catalyst photocatalyst. innovative technique enables oxidative addition insertion just using nickel, diverging significantly conventional pathway mediated by salts. The adoption this methodology holds immense promise crafting spectrum intricate compounds, particularly those significance pharmaceuticals. Detailed experimental investigations have shed light on metallaphotoredox process, further enhancing our understanding enabling advancements.
Language: Английский
Citations
0
Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: unknown
Published: July 25, 2024
Abstract Despite the existence of three competing reactions for propargyloxyoxindoles, we report a chemoselectivity switch between enantioselective propargyl [2,3]‐Wittig rearrangement and Conia‐ene‐type reactions, with suppression [1,2]‐Wittig‐type rearrangement. Using C 1 ‐symmetric imidazolidine‐pyrroloimidazolone pyridine as ligand Ni(acac) 2 Lewis acid, diverse 3‐hydroxy 3‐substituted oxindoles containing allenyl groups were obtained in up to 98 % yield 99 ee via asymmetric In presence AgOTf‐Duanphos, chiral spiro dihydrofuran given 91 through reaction.
Language: Английский
Citations
0
Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: 42(24), P. 3248 - 3254
Published: Aug. 24, 2024
Comprehensive Summary Catalytic methylative coupling of internal alkynes and aldehydes/aldimines through regioselective oxidative cyclization promoted by a phosphine–Co complex is presented. Such process constitutes an unprecedented unique approach for Co‐catalyzed generation metallacycles that reversed inherent regiochemical biases to furnish wide range allylic alcohols amides bearing tetrasubstituted alkene in up 98% yield with high regioselectivity, representing novel general strategy reversal substrate‐controlled regioselectivity metal‐catalyzed cyclization.
Language: Английский
Citations
0
Angewandte Chemie, Journal Year: 2024, Volume and Issue: 137(1)
Published: Sept. 2, 2024
Abstract Transition metal‐catalyzed radical‐based enantioconvergent reactions have become a powerful strategy to synthesize enantiopure compounds from racemic starting materials. However, existing methods primarily address precursors with central chirality, neglecting those axial chirality. Herein, we describe the reductive coupling of allenes aldehydes, facilitated by photoredox, chromium, and cobalt triple catalysis system. This method selectively affords one product sixteen possible regio‐ stereoisomers. The protocol leverages Co III −H mediated hydrogen atom transfer (MHAT) Cr‐catalyzed radical‐polar crossover for efficient stereoablation chirality asymmetric addition, respectively. Supported mechanistic insights control experiments, deuterium labeling, DFT calculations, our approach offers synthetic chemists valuable tool creating enantioenriched chiral homoallylic alcohols, promising advance strategies synthesizing complex molecules.
Language: Английский
Citations
0
Angewandte Chemie, Journal Year: 2024, Volume and Issue: 137(1)
Published: Sept. 4, 2024
Abstract Catalytic regio‐, diastereo‐ and enantioselective reductive coupling of 1,3‐dienes aldehydes through regio‐ oxidative cyclization followed by diastereoselective protonation promoted a chiral phosphine‐cobalt complex is presented. Such processes represent an unprecedented reaction pathway for cobalt catalysis that enable selective transformation the more substituted alkene in 1,3‐dienes, affording broad scope bishomoallylic alcohols without need pre‐formation stoichiometric amounts sensitive organometallic reagents up to 98 % yield, >98 : 2 regioselectivity, dr er. Application this method construction axial stereogenicity deuterated stereogenic center provided wide range multifunctional building blocks are otherwise difficult access. DFT calculations revealed origin stereoselectivity as well unique mechanism catalysis.
Language: Английский
Citations
0
Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 64(1)
Published: Sept. 4, 2024
Catalytic regio-, diastereo- and enantioselective reductive coupling of 1,3-dienes aldehydes through regio- oxidative cyclization followed by diastereoselective protonation promoted a chiral phosphine-cobalt complex is presented. Such processes represent an unprecedented reaction pathway for cobalt catalysis that enable selective transformation the more substituted alkene in 1,3-dienes, affording broad scope bishomoallylic alcohols without need pre-formation stoichiometric amounts sensitive organometallic reagents up to 98 % yield, >98 : 2 regioselectivity, dr er. Application this method construction axial stereogenicity deuterated stereogenic center provided wide range multifunctional building blocks are otherwise difficult access. DFT calculations revealed origin stereoselectivity as well unique mechanism catalysis.
Language: Английский
Citations
0