Catalytic Asymmetric Hydroalkoxylation and Formal Hydration and Hydroaminoxylation of Conjugated Dienes

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(7), P. 3915 - 3925

Published: Feb. 10, 2023

The straightforward construction of stereogenic centers bearing unprotected functional groups, as in nature, has been a persistent pursuit synthetic chemistry. Abundant applications free enantioenriched allyl alcohol and hydroxylamine motifs have made the asymmetric hydration hydroaminoxylation conjugated dienes from water hydroxylamine, respectively, intriguing efficient routes that have, however, unachievable thus far. A fundamental challenge is failure to realize transition-metal-catalyzed enantioselective C–O bond constructions via hydrofunctionalization dienes. Here, we perform comprehensive study toward stereoselective formal by synthesizing set new P,N-ligands identifying an aryl-derived oxime surrogate for both hydroxylamine. Asymmetric hydroalkoxylation with also elucidated. Furthermore, versatile derivatizations following provide indirect but concise hydrophenoxylation, hydrofluoroalkoxylation, hydrocarboxylation unreported Finally, ligand-to-ligand hydrogen transfer process proposed based on results preliminary mechanistic experiments.

Language: Английский

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Synergistic Dual Catalysis in Stereodivergent Synthesis

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(6), P. 3812 - 3844

Published: Feb. 23, 2024

Chiral skeletons with multiple stereogenic centers widely reside in nature and drugs, their relative absolute configuration often determine physiological or pharmacological properties. Stereodivergent synthesis of chiral molecules is not only great significance, but also highly challenging since the formation one diastereomers inherently preferred most asymmetric reactions. dual catalysis, introduced 2013 by Carreira group, perfectly catered to all requirements for full stereoselectivity control given reactions two catalysts are utilized a synergistic way act independently, has now been arguably efficient strategy realize stereodivergent synthesis. This comprehensive review presents an overview development enabled catalysis past ten years, providing readers fundamental attributes as well ability, scope, mechanism, limitations this strategy.

Language: Английский

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Synergistic Pd/Cu-Catalyzed 1,5-Double Chiral Inductions

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(13), P. 9241 - 9251

Published: March 19, 2024

Much attention has been focused on the catalytic asymmetric creation of single chiral centers or two adjacent stereocenters. However, construction nonadjacent stereocenters is significant importance but challenging because lack remote induction models. Herein, based a C═C bond relay strategy, we report synergistic Pd/Cu-catalyzed 1,5-double model. All four stereoisomers target products bearing 1,5-nonadjacent involving both allenyl axial and central chirality could be obtained divergently by simply changing combination catalysts with different configurations. Control experiments DFT calculations reveal novel mechanism 1,5-oxidative addition, contra-thermodynamic η3-allyl palladium shift, conjugate nucleophilic substitution, which play crucial roles in control reactivity, regio-, enantio-, diastereoselectivity. It expected that this strategy may provide general protocol for synthesis structural motifs distant

Language: Английский

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Stereodivergent Construction of Csp³−Csp³Bonds Bearing Vicinal Stereocenters by Synergistic Palladium and Phase‐Transfer Catalysis

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 62(2)

Published: Nov. 16, 2022

Abstract Synergistic catalysis has emerged as one of the most powerful tools for stereodivergent formation Csp 3 −Csp bonds bearing vicinal stereocenters. Despite many successes that have been achieved in this field, coupling reactions involving stabilized nucleophiles remain challenging because competing single‐catalysis pathway. Herein, we report a synergistic palladium/phase‐transfer catalyst system enables diastereodivergent 1,3‐dienes with nucleophile oxindoles. Both syn and anti products, quaternary tertiary stereocenters, could be selectively produced good yields high enantio‐ diastereoselectivities. Non‐covalent activation via chiral ion pair biphasic is crucial success factor achieving diastereodivergence.

Language: Английский

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Asymmetric α-allylic allenylation of β-ketocarbonyls and aldehydes by synergistic Pd/chiral primary amine catalysis

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: May 22, 2023

We herein describe an asymmetric α-allylic allenylation of β-ketocarbonyls and aldehydes with 1,3-enynes. A synergistic chiral primary amine/Pd catalyst was identified to facilitate the utilization 1,3-enynes as atom-economic achiral allene precursors. The catalysis enables construction all-carbon quaternary centers-tethered allenes bearing non-adjacent 1,3-axial central stereogenic centers in high level diastereo- enantio-selectivity. By switching configurations ligands aminocatalysts, diastereodivergence can be achieved any four diastereoisomers accessed enantio- selectivity.

Language: Английский

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Stereodivergent asymmetric hydrogenation of quinoxalines

Chem, Journal Year: 2023, Volume and Issue: 9(9), P. 2585 - 2600

Published: May 31, 2023

Language: Английский

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Synergistic Palladium/Copper‐Catalyzed 1,4‐Difunctionalization of 1,3‐Dienes for Stereodivergent Construction of 1,5‐Nonadjacent Stereocenters

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(21)

Published: March 21, 2024

Abstract The construction of two distal stereocenters through a single catalytic process is great interest in organic synthesis. While there are some successful reports regarding stereodivergent preparation 1,3‐ or 1,4‐stereocenters, the more challenged 1,5‐nonadjacent have never been achieved fashion. Herein we describe synergistic palladium/copper catalysis for 1,4‐difunctionalization reactions 1,3‐dienes, providing access to quaternary stereocenters. Because each catalysts separately controlled one newly formed stereocenters, synthesis all four diastereomers products could readily be simply by choosing an appropriate combination chiral catalysts. Experimental and computational studies supported mechanism involving Heck/Tsuji–Trost cascade reaction, origins stereoselectivity were elucidated.

Language: Английский

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Stereodivergent Construction of 1,5/1,7‐Nonadjacent Tetrasubstituted Stereocenters Enabled by Pd/Cu‐Cocatalyzed Asymmetric Heck Cascade Reaction

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(35)

Published: May 16, 2024

Abstract The construction of chiral motifs containing nonadjacent stereocenters in an enantio‐ and diastereoselective manner has long been a challenging task synthetic chemistry, especially with respect to their stereodivergent synthesis. Herein, we describe protocol that enables the 1,5/1,7‐nonadjacent tetrasubstituted through Pd/Cu‐cocatalyzed Heck cascade reaction. Notably, C=C bond relay strategy involving shift π‐allyl palladium intermediate was successfully applied asymmetric 1,7‐nonadjacent stereocenters. current method allows for efficient preparation molecules bearing two privileged scaffolds, oxindoles non‐natural α‐amino acids, good functional group tolerance. full complement four stereoisomers products could be readily accessed by simple combination metal catalysts different enantiomers.

Language: Английский

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Synergistic Catalysis Involving Palladium for Stereodivergent Csp3–Csp3 Coupling Reactions

Accounts of Chemical Research, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 31, 2024

ConspectusTransition-metal-catalyzed coupling reactions of dienes (such as 1,3-dienes, alkoxyallenes, and aminoallenes) with carbon nucleophiles have proven to be a highly effective method for creating Csp3–Csp3 bonds. These perfect atom economy typically occur under mild reaction conditions. By using chiral metal complexes catalysts, it is possible create enantioenriched molecules bearing allylic stereocenters high enantioselectivities. However, challenges arise when bonds two vicinal are constructed through this type reaction. Due the inherent diastereoselectivities, only kinetically favored diastereoisomers (either syn- or anti-product) usually obtained transition-metal catalyst system. Achieving complementary stereoisomers selectivity, which require complete control both absolute relative configurations multiple centers in single chemical transformation, impossible.Over past decade, significant advancements been made stereodivergent synthesis. Notably, iridium-related synergistic catalysis has rapidly developed alkylation reactions. these systems were limited alcohol derivatives electrophilic partners. Finding ways extend use other types crucial issue that needs addressed.In 2019, we reported first palladium-mediated system between 1,3-dienes aldimine esters. Lately, strategy successful accessing diverse substrate patterns. In Account, will summarize our laboratory's efforts developing range palladium-involved dienes. We discovered several systems, including Pd/Cu(Ag), Pd/amine, Pd/Lewis base, Pd/PTC. Additionally, dienes, such aminoallenes, serve suitable partners coupling. processes provide an efficient constructing scaffolds stereocenters. Density functional theory (DFT) calculations performed elucidate mechanism rationalize origins stereochemistry some systems. Finally, synthetic application methods demonstrated concise total synthesis number natural products bioactive molecules. It anticipated increasing chemists join research on contribute more elegant examples area. believe future development further push boundary asymmetric find innovative applications soon synthesizing complex

Language: Английский

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Umpolung Asymmetric 1,5‐Conjugate Addition via Palladium Hydride Catalysis

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 62(2)

Published: Nov. 14, 2022

Electronically matched nucleophilic 1,6-conjugate addition has been well studied and widely applied in synthetic areas. In contrast, 1,5-conjugate represents an electronically forbidden process is considered unfeasible. Here, we describe modular protocols for reactions via palladium hydride catalysis. Both synergistic Pd/organocatalyst systems are developed to catalyze reaction, followed by inter- or intramolecular [3+2] cyclization. A migratory 1,5-addition protocol established corroborate the feasibility of this umpolung concept. The products conveniently transformed into a series privileged enantioenriched motifs, including polysubstituted tetrahydrofuran, dihydrofuran, cyclopropane, cyclobutane, azetidine, oxetane, thietane, spirocycle bridged rings. Preliminary mechanistic studies involvement

Language: Английский

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