Chiral Alkyl Amine Synthesis via Catalytic Enantioselective Hydroalkylation of Enecarbamates

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(4), С. 1959 - 1967

Опубликована: Янв. 22, 2021

Chiral alkyl amines are omnipresent as bioactive molecules and synthetic intermediates. The catalytic enantioselective synthesis of from readily accessible precursors is challenging. Here we develop a nickel-catalyzed hydroalkylation method to assemble wide range chiral enecarbamates (N-Cbz-protected enamines) halides with high regio- enantioselectivity. works for both nonactivated activated able produce enantiomerically enriched two minimally differentiated α-alkyl substituents. mild conditions lead functional group tolerance, which demonstrated in the postproduct functionalization many natural products drug molecules, well building blocks key intermediates compounds.

Язык: Английский

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NiH-Catalyzed Functionalization of Remote and Proximal Olefins: New Reactions and Innovative Strategies

Accounts of Chemical Research, Год журнала: 2022, Номер 55(23), С. 3519 - 3536

Опубликована: Ноя. 9, 2022

Transition metal hydride catalyzed functionalization of remote and proximal olefins has many advantages over conventional cross-coupling reactions. It avoids the separate, prior generation stoichiometric amounts organometallic reagents use preformed reagents, which are sometimes hard to access may compromise functional group compatibility. The migratory insertion complexes generated in situ into readily available alkene starting materials, hydrometalation process, provides an attractive straightforward route alkyl intermediates, can undergo a variety sequential In particular, with synergistic combination chain-walking chemistry nickel, NiH-catalyzed undergone particularly intense development past few years. This Account aims chronicle progress made this arena terms activation modes, diverse functionalizations, chemo-, regio-, enantioselectivity.We first provide brief introduction general reaction mechanisms. Taking hydroarylation as example, four oxidation states Ni have allowed us develop two different strategies form final product: Ni(I)-H/X-Ni(II)-H platform that relies on reductants Ni(I/II/III) cycle redox-neutral or FG-Ni(II)-H reacts substrate forms products via Ni(0/II) pathway. We also demonstrate functionalization, including C-C bond-forming reactions more challenging C-N/C-S could be realized. Moreover, employment appropriate chiral ligands successfully realize corresponding asymmetric hydrofunctionalization olefins, hydroalkylation, hydroarylation, hydroalkenylation, hydroalkynylation, hydroamination. Interestingly, enantio-determining step enantioselective hydronickelation, selective oxidative addition, reductive elimination. To hydrofunctionalization, we developed ligand relay catalytic strategy simple ligands, for second coupling. novel design single, possibly structurally complex promote both steps success multicomponent convenient approach gain molecules. Finally, halides used olefin precursors cross-electrophile coupling Applications these discussed. hope will inspire future field overcome key challenges, conceptually new strategies, high-performance systems enhanced reactivity selectivity, cutting-edge catalyst design, further mechanistic studies.

Язык: Английский

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Photoinduced Hydrocarboxylation via Thiol-Catalyzed Delivery of Formate Across Activated Alkenes

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(33), С. 13022 - 13028

Опубликована: Авг. 12, 2021

Herein we disclose a new photochemical process to prepare carboxylic acids from formate salts and alkenes. This redox-neutral hydrocarboxylation proceeds in high yields across diverse functionalized alkene substrates with excellent regioselectivity. operationally simple procedure can be readily scaled batch at low photocatalyst loading (0.01% photocatalyst). Furthermore, this reaction leverage commercially available carbon isotologues enable the direct synthesis of isotopically labeled acids. Mechanistic studies support working model involving thiol-catalyzed radical chain wherein atoms are delivered substrate via CO2•– as key reactive intermediate.

Язык: Английский

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Enantioselective access to chiral aliphatic amines and alcohols via Ni-catalyzed hydroalkylations

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Май 13, 2021

Abstract Chiral aliphatic amine and alcohol derivatives are ubiquitous in pharmaceuticals, pesticides, natural products fine chemicals, yet difficult to access due the challenge differentiate between spatially electronically similar alkyl groups. Herein, we report a nickel-catalyzed enantioselective hydroalkylation of acyl enamines enol esters with halides afford enantioenriched α-branched amines good yields excellent levels enantioselectivity. The operationally simple protocol provides straightforward chiral secondary alkyl-substituted from starting materials great functional group tolerance.

Язык: Английский

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Highly Regio- and Enantioselective Reductive Coupling of Alkynes and Aldehydes via Photoredox Cobalt Dual Catalysis

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(19), С. 7306 - 7313

Опубликована: Май 5, 2021

A Co-catalyzed highly regio- and enantioselective reductive coupling of alkynes aldehydes has been developed under visible light photoredox dual catalysis. variety enantioenriched allylic alcohols have obtained by using unsymmetrical internal commercially available catalyst, chiral ligand, reagents. It is noteworthy that this approach considerable advantages, such as excellent (>95:5 for >40 examples), stereo- (up to >95:5 E/Z), enantioselectivity (92-99% ee, >35 examples) control, mild reaction conditions, broad substrate scope, good functional group compatibility, making it a great improvement alkyne-aldehyde reactions.

Язык: Английский

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Challenges and recent advancements in the transformation of CO₂into carboxylic acids: straightforward assembly with homogeneous 3d metals

Chemical Society Reviews, Год журнала: 2022, Номер 51(22), С. 9371 - 9423

Опубликована: Янв. 1, 2022

The transformation of carbon dioxide (CO2) into useful chemicals, advanced materials, and energy is a long-standing challenge in both fundamental science industry. In recent years, utilization CO2 the presence inexpensive non-negligible environmentally friendly 3d metal-based catalysts (Fe, Mn, Co, Ni, Cu Ti) has become one most attractive topics. Particular attention been given to synthesis carboxylic acids their derivatives since these molecules serve as key intermediates chemical, fertilizer, pharmaceutical sectors. Considering numerous challenges linked with reactivity, number research groups have recently focused on by following thermo-, photo-, electrochemical strategies. However, facile access such remains vital catalysis organic owing high stability molecule which atom highest oxidation state. Another hurdle solve selectivity issue caused reaction different catalytic systems reactive functional group-containing molecules. Despite all issues, wide range transition applied this direction, but cheaper price inherent metals are at forefront domain. these, we aim summarise advances (over past five years) 3d-metal complexes reactivity towards activation for acids. Furthermore, discuss current trends, knowledge gaps, invigorating perspectives future advances.

Язык: Английский

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Ligand-Controlled Cobalt-Catalyzed Regiodivergent Alkyne Hydroalkylation

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(30), С. 13961 - 13972

Опубликована: Июль 22, 2022

Regiodivergent alkyne hydroalkylation to generate different isomers of an alkene from the same starting material would be beneficial; however, it remains a challenge. Herein, we report ligand-controlled cobalt-catalyzed regiodivergent hydroalkylation. The sensible selection bisoxazoline (L1) and pyridine-oxazoline (L8) ligands led reliable predictable protocols that provided (E)-1,2-disubstituted 1,1-disubstituted alkenes with high E/Z stereoselectivity regioisomeric ratio identical terminal alkyl halide substrates produced trisubstituted in case internal alkynes. This method exhibits broad scope for alkynes wide range activated unactivated halides shows excellent functional group compatibility.

Язык: Английский

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Anti-Markovnikov Intermolecular Hydroamination of Alkenes and Alkynes: A Mechanistic View

Chemical Reviews, Год журнала: 2023, Номер 123(15), С. 9139 - 9203

Опубликована: Июль 5, 2023

Hydroamination, the addition of an N–H bond across a C–C multiple bond, is reaction with great synthetic potential. Important advances have been made in last decades concerning catalysis these reactions. However, controlling regioselectivity amine toward formation anti-Markovnikov products (addition to less substituted carbon) still remains challenge, particularly intermolecular hydroaminations alkenes and alkynes. The goal this review collect systems which hydroamination terminal alkynes has achieved. focus will be placed on mechanistic aspects such reactions, discern step at decided unravel factors that favor regioselectivity. In processes entailing direct alternative pathways, involving several reactions accomplish (formal processes), also discussed review. catalysts gathered embrace most metal groups Periodic Table. Finally, section discussing radical-mediated metal-free approaches, as well heterogeneous catalyzed processes, included.

Язык: Английский

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Synthetic Advantages of Defluorinative C−F Bond Functionalization

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(49)

Опубликована: Авг. 22, 2023

Abstract Much progress has been made in the development of methods to both create compounds that contain C−F bonds and functionalize bonds. As such, are becoming common versatile synthetic functional handles. This review summarizes advantages defluorinative functionalization reactions for small molecule synthesis. The coverage is organized by type carbon framework fluorine attached mono‐ polyfluorinated motifs. main challenges, opportunities advances discussed each class organofluorine. Most text focuses on case studies illustrate how defluorofunctionalization can improve routes targets or properties enable unique mechanisms reactions. broader goal showcase incorporating exploiting design routes, improvement specific advent new methods.

Язык: Английский

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Photoenzymatic enantioselective intermolecular radical hydroamination

Nature Catalysis, Год журнала: 2023, Номер 6(8), С. 687 - 694

Опубликована: Июль 31, 2023

Язык: Английский

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