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19 Oct 07:59

Frontispiece: Dimensioning the Term Carbenoid

by Ana Caballero, Pedro J. Pérez
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A carbenoid species consists of a tetrasubstituted carbon atom bearing a leaving group X and a metal–carbon bond, from which extrusion of X triggers the elimination/transfer of the CR1R2 unit. This is the case of the largely known Simmons–Smith reaction (based on Zn) or the more recent gold-based carbenoid LAuCH2Cl described by Echavarren and co-workers. In the context of metal-induced carbene transfer from a diazo compound, a clear distinction must be made between the transient carbenoid and metal–carbene intermediates. For more information see the Concept article by A. Caballero and P. J. Pérez on page 14389 ff.

16 Oct 12:04

Computationally Guided Catalyst Design in the Type I Dynamic Kinetic Asymmetric Pauson–Khand Reaction of Allenyl Acetates

by Lauren C. Burrows, Luke T. Jesikiewicz, Gang Lu, Steven J. Geib, Peng Liu and Kay M. Brummond

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Journal of the American Chemical Society
DOI: 10.1021/jacs.7b07121
16 Oct 11:56

Rhodium-Catalyzed Asymmetric 1,4-Addition Reactions of Aryl Boronic Acids with Nitroalkenes: Reaction Mechanism and Development of Homogeneous and Heterogeneous Catalysts

Chem. Sci., 2017, Accepted Manuscript
DOI: 10.1039/C7SC03025H, Edge Article
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Hiroyuki Miyamura, Kohei Nishino, Tomohiro Yasukawa, Shu Kobayashi
Asymmetric 1,4-addition reactions with nitroalkenes are valuable because the resulting chiral nitro compounds can be converted to various useful species often used as chiral building blocks in drug and natural...
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02 Oct 08:51

Lewis Acid Enabled Copper-Catalyzed Asymmetric Synthesis of Chiral β-Substituted Amides

by Mamen Rodríguez-Fernández, Xingchen Yan, Juan F. Collados, Paul B. White and Syuzanna R. Harutyunyan

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Journal of the American Chemical Society
DOI: 10.1021/jacs.7b07344
16 Aug 08:38

Rh-Catalyzed Conjugate Addition of Aryl and Alkenyl Boronic Acids to α-Methylene-β-lactones: Stereoselective Synthesis of trans-3,4-Disubstituted β-Lactones

by Christian A. Malapit, Irungu K. Luvaga, Donald R. Caldwell, Nicholas K. Schipper and Amy R. Howell

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Organic Letters
DOI: 10.1021/acs.orglett.7b01994
07 Aug 09:01

N-heterocyclic Carbene–Cu-Catalyzed Enantioselective Conjugate Additions with Alkenylboronic Esters as Nucleophiles

by Qinglei Chong, Zhenting Yue, Shuoqing Zhang, Chonglei Ji, Fengchang Cheng, Haiyan Zhang, Xin Hong and Fanke Meng

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ACS Catalysis
DOI: 10.1021/acscatal.7b02132
09 Jun 09:04

Dynamic Kinetic Resolution in Rhodium-Catalyzed Asymmetric Arylation of Phospholene Oxides

by Kelvin Meng-Hui Lim and Tamio Hayashi

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Journal of the American Chemical Society
DOI: 10.1021/jacs.7b04570
08 Jun 14:57

Enantioselective copper catalysed, direct functionalisation of allenes via allyl copper intermediates

Chem. Sci., 2017, 8,5240-5247
DOI: 10.1039/C7SC01968H, Minireview
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Alexander P. Pulis, Kay Yeung, David J. Procter
We explore the breadth of the copper catalysed functionalisation of allenes, which enables efficient access to enantioenriched, densely functionalised molecules.
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24 Apr 16:07

Kinetic resolution of racemic 2-substituted 1,2-dihydroquinolines via asymmetric Cu-catalyzed borylation

Chem. Sci., 2017, 8,4558-4564
DOI: 10.1039/C7SC01556A, Edge Article
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Duanyang Kong, Suna Han, Rui Wang, Meina Li, Guofu Zi, Guohua Hou
A highly efficient kinetic resolution of racemic 2-substituted 1,2-dihydroquinolines via asymmetric Cu-catalyzed borylation has been realized for the first time to afford chiral 3-boryl-1,2,3,4-tetrahydroquinolines and recover 2-substituted 1,2-dihydroquinolines with excellent enantioselectivities and selectivity factors of up to 569.
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01 Apr 10:20

Regio- and stereospecific rhodium-catalyzed allylic alkylation with an acyl anion equivalent: an approach to acyclic [small alpha]-ternary [small beta],[gamma]-unsaturated aryl ketones

Chem. Sci., 2017, 8,4001-4005
DOI: 10.1039/C6SC05705E, Edge Article
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Ben W. H. Turnbull, Jungha Chae, Samuel Oliver, P. Andrew Evans
The regio- and stereospecific rhodium-catalyzed allylic alkylation of secondary allylic carbonates with cyanohydrin pronucleophiles facilitates the direct construction of acyclic [small alpha]-ternary [small beta],[gamma]-unsaturated aryl ketones.
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24 Mar 09:40

Copper-Catalyzed, Stereoselective Cross-Coupling of Cyclic Allyl Boronic Acids with α-Diazoketones

by Dong Wang and Kálmán J. Szabó

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Organic Letters
DOI: 10.1021/acs.orglett.7b00433
06 Mar 15:30

Synthesis of Complex Tertiary Glycolates by Enantioconvergent Arylation of Stereochemically Labile α-Keto Esters

by Samuel L. Bartlett, Kimberly M. Keiter and Jeffrey S. Johnson

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Journal of the American Chemical Society
DOI: 10.1021/jacs.7b00943
28 Jan 16:58

Rhodium-Catalyzed Hydrofunctionalization: Enantioselective Coupling of Indolines and 1,3-Dienes

by Xiao-Hui Yang and Vy M. Dong

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Journal of the American Chemical Society
DOI: 10.1021/jacs.6b12307
13 Dec 11:03

Palladium-Catalyzed Asymmetric α-Arylation of Alkylnitriles

by Zhiwei Jiao, Kwok Wei Chee and Jianrong “Steve” Zhou

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Journal of the American Chemical Society
DOI: 10.1021/jacs.6b11610
06 Dec 17:23

F– Nucleophilic-Addition-Induced Allylic Alkylation

by Panpan Tian, Cheng-Qiang Wang, Sai-Hu Cai, Shengjin Song, Lu Ye, Chao Feng and Teck-Peng Loh

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Journal of the American Chemical Society
DOI: 10.1021/jacs.6b11205
26 Oct 15:01

Terminal-Selective Functionalization of Alkyl Chains by Regioconvergent Cross-Coupling

by Stéphanie Dupuy, Ke-Feng Zhang, Anne-Sophie Goutierre, Olivier Baudoin

Abstract

Hydrocarbons are still the most important precursors of functionalized organic molecules, which has stirred interest in the discovery of new C−H bond functionalization methods. We describe herein a new step-economical approach that enables C−C bonds to be constructed at the terminal position of linear alkanes. First, we show that secondary alkyl bromides can undergo in situ conversion into alkyl zinc bromides and regioconvergent Negishi coupling with aryl or alkenyl triflates. The use of a suitable phosphine ligand favoring Pd migration enabled the selective formation of the linear cross-coupling product. Subsequently, mixtures of secondary alkyl bromides were prepared from linear alkanes by standard bromination, and regioconvergent cross-coupling then provided access to the corresponding linear arylation product in only two steps.

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Remote control: Secondary alkyl bromides underwent regioconvergent Barbier–Negishi coupling with aryl triflates in the presence of a phosphine ligand favoring Pd migration to give linear products with good to high linear/branched selectivity (see scheme). This procedure was also applied to mixtures of secondary alkyl bromides, prepared from linear alkanes by standard bromination.

25 Oct 18:40

Enantioselective Palladium-Catalyzed Alkenylation of Trisubstituted Alkenols To Form Allylic Quaternary Centers

by Harshkumar H. Patel and Matthew S. Sigman

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Journal of the American Chemical Society
DOI: 10.1021/jacs.6b09649
21 Oct 14:10

Enantioselective Formation of All-Carbon Quaternary Centers via C–H Functionalization of Methanol: Iridium-Catalyzed Diene Hydrohydroxymethylation

by Khoa D. Nguyen, Daniel Herkommer and Michael J. Krische

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Journal of the American Chemical Society
DOI: 10.1021/jacs.6b09333
27 Sep 11:12

Enantioselective Pd-Catalyzed Allylic Alkylation Reactions of Dihydropyrido[1,2-a]indolone Substrates: Efficient Syntheses of (−)-Goniomitine, (+)-Aspidospermidine, and (−)-Quebrachamine

by Beau P. Pritchett, Jun Kikuchi, Yoshitaka Numajiri, Brian M. Stoltz

Abstract

The successful application of dihydropyrido[1,2-a]indolone (DHPI) substrates in Pd-catalyzed asymmetric allylic alkylation chemistry facilitates rapid access to multiple alkaloid frameworks in an enantioselective fashion. Strategic bromination at the indole C3 position greatly improved the allylic alkylation chemistry and enabled a highly efficient Negishi cross-coupling downstream. The first catalytic enantioselective total synthesis of (−)-goniomitine, along with divergent formal syntheses of (+)-aspidospermidine and (−)-quebrachamine, are reported herein.

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Magnum (DH)PI: Application of dihydropyrido[1,2-a]indolone (DHPI) substrates in Pd-catalyzed asymmetric allylic alkylation chemistry enables rapid access to multiple alkaloid frameworks in an enantioselective fashion. The first catalytic enantioselective total synthesis of (−)-goniomitine, along with divergent formal syntheses of (+)-aspidospermidine and (−)-quebrachamine are reported.

26 Sep 16:39

Rh-Catalyzed Conjugate Addition of Arylzinc Chlorides to Thiochromones: A Highly Enantioselective Pathway for Accessing Chiral Thioflavanones

by Ling Meng, Ming Yu Jin and Jun Wang

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Organic Letters
DOI: 10.1021/acs.orglett.6b02453
23 Sep 08:08

Copper-Catalyzed Amidation of Primary and Secondary Alkyl Boronic Esters

by Luis M. Mori-Quiroz, Kirk W. Shimkin, Sina Rezazadeh, Ryan A. Kozlowski, Donald A. Watson

Abstract

The oxidative copper-catalyzed cross-coupling of functionalized alkyl boronic esters with primary amides is reported. Through the identification of appropriate diketimine ligands, conditions for efficient coupling of both primary and secondary alkyl boronic esters with diverse primary amides, including acetamide, have been developed.

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NacNac time! The oxidative copper-catalyzed cross-coupling of functionalized alkyl boronic esters with primary amides is reported. Through the identification of appropriate diketimine ligands, conditions for efficient coupling of both primary and secondary alkyl boronic esters with diverse primary amides, including acetamide, have been developed (see scheme).

15 Sep 13:59

Enantioselective allylic alkylation of stereodefined polysubstituted copper enolates as an entry to acyclic quaternary carbon stereocentres

Chem. Sci., 2016, Advance Article
DOI: 10.1039/C6SC03036J, Edge Article
Open Access Open Access
Creative Commons Licence&nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
Zackaria Nairoukh, Gunda G. K. S. Narayana Kumar, Yury Minko, Ilan Marek
A sequence of regio- and stereoselective carbometalation followed by oxidation of ynamides leads to stereodefined fully substituted enolates that subsequently react with various functionalized allyl bromide reagents to provide the enantiomerically pure quaternary carbon stereocentre in the [small alpha]-position to the carbonyl group.
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06 Sep 21:26

Enantioselective Synthesis of Di- and Tri-Arylated All-Carbon Quaternary Stereocenters via Copper-Catalyzed Allylic Arylations with Organolithium Compounds

by Sureshbabu Guduguntla, Jean-Baptiste Gualtierotti, Shermin S. Goh and Ben L. Feringa

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ACS Catalysis
DOI: 10.1021/acscatal.6b01681