Copper‐Catalyzed Asymmetric Acylboration of 1,3‐Butadienylboronate with Acyl Fluorides

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(43)

Опубликована: Сен. 15, 2023

Abstract We report herein a Cu‐catalyzed regio‐, diastereo‐ and enantioselective acylboration of 1,3‐butadienylboronate with acyl fluorides. Under the developed conditions, reactions provide ( Z )‐β,γ‐unsaturated ketones bearing an α‐tertiary stereocenter high ‐selectivity excellent enantioselectivities. While direct access to highly enantioenriched E ‐isomers was not successful, we showed that such molecules can be synthesized optical purities via Pd‐catalyzed alkene isomerization from corresponding ‐isomers. The orthogonal chemical reactivities functional groups embedded in ketone products allow for diverse chemoselective transformations, which provides valuable platform further derivatization.

Язык: Английский

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Rhodium(I) Catalyzed Hydroacylation Reactions of Alkenyl Compounds

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер 366(8), С. 1707 - 1718

Опубликована: Март 5, 2024

Abstract Transition‐metal‐catalyzed hydroacylation of unsaturated substrates with aldehydes involving the formyl C( sp 2 )−H bond activation provides an expedient and efficient access to carbonyl compounds such as ketones esters, which are a class important scaffolds in natural products drug development. Recently, extensive attention has been paid reactions components containing alkenyl moiety that can trigger regioselective transformation presence transition metal catalyst. In this review, we summarize constructive endeavors rhodium(I)‐catalyzed (formal) from 2018, plausible pathway is also dissected offer some insights into reaction mechanism.

Язык: Английский

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CoH-catalyzed asymmetric remote hydroalkylation of heterocyclic alkenes: a rapid approach to chiral five-membered S- and O-heterocycles

Chemical Science, Год журнала: 2024, Номер 15(23), С. 8888 - 8895

Опубликована: Янв. 1, 2024

A highly efficient method achieves precise construction of alkyl chiral centers at remote C3-positions in five-membered S/O-heterocycles via cobalt-catalyzed asymmetric hydroalkylation heterocyclic alkenes.

Язык: Английский

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Ligand Effects in Carboxylic Ester- and Aldehyde-Assisted β-C–H Activation in Regiodivergent and Enantioselective Cycloisomerization–Hydroalkenylation and Cycloisomerization–Hydroarylation, and [2 + 2 + 2]-Cycloadditions of 1,6-Enynes

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(27), С. 18753 - 18770

Опубликована: Июнь 27, 2024

Herein, we report room temperature, atom-economic protocols for high regio- and enantioselective tandem cycloisomerization–hydroarylation cycloisomerization–hydroalkenylation of 1,6-enynes leading to vicinal carba-functionalized pyrrolidines, tetrahydrofurans, cyclopentanes. The latter steps in these processes involve carbonyl-coordination-assisted ortho-C–H activation aromatic aldehydes esters, and, a similar, yet rarely seen, β-C–H the case acrylates. Synthetically useful versions such reactions are rare limited C2–H indoles pyrroles. A similar reaction is also observed with N-vinylphthalimide, which has carbonyl group suitable C–H activation. dibenzooxaphosphole ligand, (2S,2S′,3S,3S′)-MeO-BIBOP was uniquely identified as crucial achieving challenging enantioselectivity. This methodology gives access substituted five-membered carbo- heterocyclic compounds good yields excellent enantioselectivities under low catalyst loading. primary KIE 3.5 an intermolecular competition experiment methyl benzoate d5-methyl benzoate, indicates that cleavage turnover-limiting step this process. Unlike acrylates, undergoes exclusive hydroalkenylation, β, γ-unsaturated ester, but-3-enoate, highly cycloisomerization-coupling sequence 1,6-enyne giving either [2 + 2 2]-cycloaddition (S, S)-BDPP or hydroalkenylation (2S,2′S,3S,3′S)-MeO-BIBOP depending on ligand employed. (E)-configuration newly formed double bond at terminal alkynyl carbon (of starting enyne) product β,γ-unsaturated ester suggests more classical migratory insertion-β-hydride elimination route formation product.

Язык: Английский

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Intermolecular Metal-Catalyzed C–C Coupling of Unactivated Alcohols or Aldehydes for Convergent Ketone Construction beyond Premetalated Reagents

ACS Catalysis, Год журнала: 2023, Номер 13(16), С. 10976 - 10987

Опубликована: Авг. 4, 2023

Intermolecular metal-catalyzed C–C couplings of unactivated primary alcohols or aldehydes to form ketones are catalogued. Reactions classified on the basis pronucleophile. Protocols involving premetalated reagents reactants that incorporate directing groups not covered. These methods represent an emerging alternative classical multistep protocols for ketone construction exploit and/or steps devoted redox manipulations and carboxylic acid derivatization.

Язык: Английский

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