Rh(III)-Catalyzed Intra- and Intermolecular 3,4-Difunctionalization of 1,3-Dienes via Rh(III)-π-Allyl Amidation with 1,4,2-Dioxazolones DOI
Finn Burg, Tomislav Rovis

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(15), P. 9690 - 9697

Published: July 26, 2022

We herein report a modular strategy, which enables Rh(III)-catalyzed diastereoselective 3,4-amino oxygenation and diamination of 1,3-dienes using different O- N-nucleophiles in combination with readily available 3-substituted 1,4,2-dioxazolones (78 examples, 37–91% yield). Previous attempts to functionalize the internal double bond rested on use plain alcoholic solvents as nucleophilic coupling partners thus dramatically limiting scope this transformation. have now identified hexafluoroisopropanol non-nucleophilic solvent that allows diverse nucleophiles greatly expands scope, including an unprecedented amino hydroxylation selectively install valuable, unprotected β-amino alcohols across 1,3-dienes. Moreover, various elaborate prove be compatible providing unique access complex organic molecules. Finally, method is employed series intramolecular reactions deliver valuable nitrogen heterocycles well γ- δ-lactones.

Language: Английский

Strategic evolution in transition metal-catalyzed directed C–H bond activation and future directions DOI
Supriya Rej, Amrita Das, Naoto Chatani

et al.

Coordination Chemistry Reviews, Journal Year: 2020, Volume and Issue: 431, P. 213683 - 213683

Published: Dec. 9, 2020

Language: Английский

Citations

224
Dioxazolones: Stable Substrates for the Catalytic Transfer of Acyl Nitrenes DOI Creative Commons

Kaj M. van Vliet,

Bas de Bruin

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(8), P. 4751 - 4769

Published: March 30, 2020

Dioxazolones are a convenient class of acyl nitrene transfer reagents. Their application in homogeneous transition-metal catalysis has led to many new amidation reactions. typically activated by transition metals at relatively low reaction temperatures. The metal nitrenoids formed decarboxylative activation dioxazolones generally electron deficient and commonly react concerted fashion. "Intermolecular" insertion reactions involving preactivated C–H bonds ("inner-sphere" mechanism) easily compete with the Curtius-type rearrangement, but for intramolecular "direct" transfer/insertion nonpreactivated substrates (i.e., without preceding formation metal–carbon or metal–hydride bonds) extensive ligand optimization is important prevent such unwanted side ease dioxazolone synthesis, CO2 gas as sole byproduct from dioxazolones, importance general development several interesting producing N-aryl amides, oxazoles, lactams. Since proceeds under mild conditions, stereo- enantioselective also possible, which useful synthesis bioactive nitrogen-containing compounds. This review provides an overview these reported recent years.

Language: Английский

Citations

175
Mechanism-Guided Development of Transition-Metal-Catalyzed C–N Bond-Forming Reactions Using Dioxazolones as the Versatile Amidating Source DOI
Seung Youn Hong, Yeongyu Hwang, Minhan Lee

et al.

Accounts of Chemical Research, Journal Year: 2021, Volume and Issue: 54(11), P. 2683 - 2700

Published: May 12, 2021

ConspectusCatalytic reactions that construct carbon–nitrogen bonds are one of central themes in both synthetic and medicinal chemistry since the obtainable nitrogen-containing motifs commonly encountered natural products have also seen a growing prominence as key structural features marketed drugs preclinical candidates. Pd-catalyzed cross-couplings, such Buchwald–Hartwig amination, at forefront methods practical settings. However, they require prefunctionalized substrates (hetero)aryl halides must be prepared independently, often by multiple operations. One emerging way to circumvent these preparatory steps directly convert ubiquitous C–H into valuable C–N is catalytic which allows chemists devise shorter more efficient retrosynthetic schemes. The past two decades witnessed considerable progress expanding repertoire this strategy, especially identifying effective amino group precursors. In context, dioxazolones experienced dramatic resurgence recent years versatile nitrogen source combination with transition-metal catalyst systems facilitate decarboxylation access metal-acylnitrenoid intermediates. addition their high robustness easy accessibility from abundant carboxylic acids, unique reactivity transient intermediates amido transfer has led fruitful journey for mild amidation reactions.This Account summarizes our contributions development bond-forming using nitrenoid precursors, categorized subsets according mechanistic differences: inner- versus outer-sphere pathways. first section describes how we could unveil potential realm inner-sphere amidation, where demonstrated serve not only manageable alternatives acyl azides but highly reagents significantly reduce loading temperature. Taking advantage conditions 9 Cp*M complexes (M = Rh, Ir, Co) or isoelectronic Ru species, dramatically expanded accessible scope. Mechanistic investigations revealed putative metal-nitrenoid species involved intermediate during catalysis, leads facile bond formation. On basis underpinning, succeeded developing novel platforms harness intermediacy metal-nitrenoids explore insertion via an pathway. Indeed, tailored catalysts were capable suppressing competitive Curtius-type decomposition, thus granting lactam products. We further repurposed upon modification chelating ligands identity transition metal achieve three goals: (i) addressing selectivity issues control regio-, chemo-, enantioselectivities, (ii) sustainable catalysis first-low metals, (iii) navigating chemical space (di)functionalization alkenes/alkynes. Together own research efforts, highlighted herein some important relevant advances other groups. finally conclude brief overview eye toward developments.

Language: Английский

Citations

171
Nitrene-mediated intermolecular N–N coupling for efficient synthesis of hydrazides DOI
Hao Wang, Hoimin Jung, Fangfang Song

et al.

Nature Chemistry, Journal Year: 2021, Volume and Issue: 13(4), P. 378 - 385

Published: March 22, 2021

Language: Английский

Citations

112
Asymmetric intermolecular allylic C–H amination of alkenes with aliphatic amines DOI
Kelvin Pak Shing Cheung, Jian Fang, Kallol Mukherjee

et al.

Science, Journal Year: 2022, Volume and Issue: 378(6625), P. 1207 - 1213

Published: Dec. 15, 2022

Aliphatic allylic amines are found in a great variety of complex and biorelevant molecules. The direct C-H amination alkenes serves as the most straightforward method toward these motifs. However, use widely available internal with aliphatic this transformation remains synthetic challenge. In particular, palladium catalysis faces twin challenges inefficient coordination Pd(II) to but excessively tight therefore inhibitory by basic amines. We report general solution problems. developed protocol, contrast classical Pd(II/0) scenario, operates through blue light-induced Pd(0/I/II) manifold mild aryl bromide oxidant. This open-shell approach also enables enantio- diastereoselective amination.

Language: Английский

Citations

108
Designing a Planar Chiral Rhodium Indenyl Catalyst for Regio- and Enantioselective Allylic C–H Amidation DOI
Caitlin M. B. Farr, Amaan M. Kazerouni, Bohyun Park

et al.

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(32), P. 13996 - 14004

Published: July 15, 2020

Chiral variants of group IX Cp and Cp* catalysts are well established catalyze a broad range reactions with high levels enantioselectivity. Enantiocontrol in these systems results from ligand design that focuses on appropriate steric blocking. Herein we report the development new planar chiral indenyl rhodium complex for enantioselective C–H functionalization catalysis. The is based establishing electronic asymmetry catalyst, to control enantioselectivity during reactions. easily synthesized commercially available starting materials capable catalyzing asymmetric allylic amidation unactivated olefins, delivering wide high-value enantioenriched amide products good yields excellent regio- Computational studies suggest cleavage rate- enantio-determining, while reductive C–N coupling RhV-nitrenoid intermediate regio-determining.

Language: Английский

Citations

130
Non-C2-Symmetric Chiral-at-Ruthenium Catalyst for Highly Efficient Enantioselective Intramolecular C(sp3)–H Amidation DOI
Zijun Zhou, Shuming Chen,

Yubiao Hong

et al.

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(48), P. 19048 - 19057

Published: Nov. 21, 2019

A new class of chiral ruthenium catalysts is introduced in which cyclometalated by two 7-methyl-1,7-phenanthrolinium heterocycles, resulting chelating pyridylidene remote N-heterocyclic carbene ligands (rNHCs). The overall chirality results from a stereogenic metal center featuring either Λ or Δ absolute configuration. This work features the importance relative metal-centered stereochemistry. Only non-C2-symmetric chiral-at-ruthenium complexes display unprecedented catalytic activity for intramolecular C(sp3)–H amidation 1,4,2-dioxazol-5-ones to provide γ-lactams with up 99:1 er and catalyst loadings down 0.005 mol % (up 11 200 TON), while C2-symmetric diastereomer favors an undesired Curtius-type rearrangement. DFT calculations elucidate origins superior C–H reactivity displayed compared related counterparts.

Language: Английский

Citations

120
α-Branched amines by catalytic 1,1-addition of C–H bonds and aminating agents to terminal alkenes DOI
Soham Maity,

Tyler J. Potter,

Jonathan A. Ellman

et al.

Nature Catalysis, Journal Year: 2019, Volume and Issue: 2(9), P. 756 - 762

Published: Aug. 12, 2019

Language: Английский

Citations

113
An Update of Transition Metal-Catalyzed Decarboxylative Transformations of Cyclic Carbonates and Carbamates DOI Creative Commons

Linhong Zuo,

Teng Liu,

Xiaowei Chang

et al.

Molecules, Journal Year: 2019, Volume and Issue: 24(21), P. 3930 - 3930

Published: Oct. 31, 2019

Functionalized cyclic organic carbonates and carbamates are frequently used in a number of transition metal-catalyzed decarboxylative reactions for the construction interesting molecules. These transformations have attracted more research attention recent years mainly due to their advantages less waste generation versatile reactivities. On basis previous reviews on this hot topic, present review will focus development functionalized last two years.

Language: Английский

Citations

95
Interweaving Visible‐Light and Iron Catalysis for Nitrene Formation and Transformation with Dioxazolones DOI

Jingjing Tang,

Xiaoqiang Yu, Yi Wang

et al.

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(30), P. 16426 - 16435

Published: April 12, 2021

Abstract Herein, visible‐light‐driven iron‐catalyzed nitrene transfer reactions with dioxazolones for intermolecular C(sp 3 )‐N, N=S, and N=P bond formation are described. These occur exogenous‐ligand‐free process feature satisfactory to excellent yields (up 99 %), an ample substrate scope (109 examples) under mild reaction conditions. In contrast intramolecular C−H amidations strategies, regioselective amidation via visible‐light‐induced is devised. Mechanistic studies indicate that the proceeds a radical pathway. Computational show decarboxylation of dioxazolone depends on conversion ground sextet state dioxazolone‐bounding iron species quartet spin visible‐light irradiation.

Language: Английский

Citations

91