Enantioselective Copper-Catalyzed Ring-Opening Diboration of Arylidenecyclopropanes to Access Chiral Skipped 1,4- and 1,3-Diboronates

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(8), P. 5366 - 5374

Published: Feb. 14, 2024

Two enantioselective approaches to synthesize chiral skipped diboronate compounds have been developed, relying on copper-catalyzed one-pot asymmetric ring-opening diboration of arylidenecyclopropanes. A wide range arylidenecyclopropanes react smoothly with HBpin in the presence CuOAc and (R)-DTBM-Segphos, affording 1,4-diboronates high enantioselectivity (up 99% ee). Meanwhile, a variety selectively B2pin2 (S,S)-Ph-BPE sequential addition MeOH, providing 1,3-diboronates 98% These enantioenriched 1,3- can undergo various enantiospecific transformations minimal loss their enantiopurity. Mechanistic studies reveal that these two processes start CuH-catalyzed hydroboration form mixture Z/E-homoallyl boronate intermediates, which subsequently second or Cu-Bpin-catalyzed protoboration produce 1,3-diboronates, respectively.

Language: Английский

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PolyBorylated Alkenes as Energy‐Transfer Reactive Groups: Access to Multi‐Borylated Cyclobutanes Combined with Hydrogen Atom Transfer Event

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(25)

Published: April 11, 2024

Abstract While polyborylated alkenes are being recognized for their elevated status as highly valuable reagents in modern organic synthesis, allowing efficient access to a diverse array of transformations, including the formation C−C and C‐heteroatom bonds, potential energy‐transfer reactive groups has remained unexplored. Yet, this holds key generating elusive biradical species, which can be captured by olefins, thereby leading construction new highly‐borylated scaffolds. Herein, we report designed strategy photosensitized [2+2]‐cycloadditions poly‐borylated with various olefins enabling regioselective synthesis cyclobutane motifs, 1,1‐di‐, 1,1,2‐tri‐, 1,1,2,2‐tetra‐borylated cyclobutanes. In fact, these compounds belong family that presently lacks synthetic pathways. Interestingly, when α‐methylstyrene was used, reaction involves an interesting 1,5‐hydrogen atom transfer (HAT). Mechanistic deuterium‐labeling studies have provided insight into outcome process. addition, cyclobutanes then demonstrated useful selective oxidation processes resulting cyclobutanones γ‐lactones.

Language: Английский

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Enantioselective Suzuki cross-coupling of 1,2-diboryl cyclopropanes

Chemical Science, Journal Year: 2023, Volume and Issue: 14(6), P. 1575 - 1581

Published: Jan. 1, 2023

Herein, we describe the catalytic enantioselective cross-coupling of 1,2-bisboronic esters. Prior work on group specific cross coupling is limited to use geminal bis-boronates. This desymmetrization provides a novel approach prepare enantioenriched cyclopropyl boronates with three contiguous stereocenters, that could be further derivatized through selective functionalization carbon-boron bond. Our results suggest transmetallation, which enantiodetermining step, takes place retention stereochemistry at carbon.

Language: Английский

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Catalytic Asymmetric Transfer Hydrogenation of Acylboronates: BMIDA as the Privileged Directing Group

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(29), P. 20357 - 20369

Published: June 13, 2024

Developing a general, highly efficient, and enantioselective catalytic method for the synthesis of chiral alcohols is still formidable challenge. We report in this article asymmetric transfer hydrogenation (ATH) N-methyliminodiacetyl (MIDA) acylboronates as general substrate-independent entry to enantioenriched secondary alcohols. ATH acyl-MIDA-boronates with (het)aryl, alkyl, alkynyl, alkenyl, carbonyl substituents delivers variety α-boryl The latter are used range stereospecific transformations based on boron moiety, enabling carbinols two closely related α-substituents, which cannot be obtained high enantioselectivities using direct methods, such (R)-cloperastine intermediate. Computational studies illustrate that BMIDA group privileged enantioselectivity-directing Noyori–Ikariya compared conventionally aryl alkynyl groups due favorable CH–O attractive electrostatic interaction between η6-arene-CH catalyst σ-bonded oxygen atoms BMIDA. work expands domain conventional shows its huge potential addressing challenges symmetric synthesis.

Language: Английский

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The current utility and future potential of multiborylated alkanes

Nature Reviews Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 26, 2024

Language: Английский

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Catalytic Selective Functionalization of Poly(organoborons)^†

Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 28, 2024

Comprehensive Summary Organoborons are commonly used building blocks for rapidly increasing molecular complexity. Although significant progress has been made in the selective functionalization of mono‐organoborons, site‐selective poly(organoborons) attracted substantial interest organic synthesis, pharmaceuticals, and agrochemicals due to presence multiple potential reaction sites. This review discusses various activation modes target C–B bond, with diverse transformations being achieved both a efficient manner. Recent advances catalytic 1, n ‐diboronates through ionic radical pathways highlighted. Furthermore, we summarize existing challenges future research directions this field. Key Scientists In 1993, Suzuki, Miyaura coworkers developed pioneering example arylation towards cis‐1,2‐bis(boryl) alkenes, marking inception The Morken group contributions asymmetric diboration alkenes realized elegant these compounds since 2004. 2016, Fernández colleagues internal bond tri(boronates). Since 2019, Aggarwal Giese‐type addition at more substituted 1,2‐bis(boronic) esters photoredox catalysis. controllable regiodivergent alkynylation 1,3‐bis(boronic) was by Gao 2023. Recently, Qin conducted on programmable late‐stage bridge‐substituted bicyclo[1.1.1]pentane (BCP) bis‐boronates. 2013, stereoselective have several groups, including those led Chen. summarizes latest most developments field 1993.

Language: Английский

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Recent Advances in Catalytic Asymmetric Synthesis of Chiral 1,2-Bis(boronic) Esters

Chinese Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 44(5), P. 1385 - 1385

Published: Jan. 1, 2024

Chiral 1,2-bis(boronic) esters are essential building blocks in the field of synthetic chemistry, and their catalytic asymmetric synthesis has attracted significant interest chemists.Recently, diboration olefins, using transition metals chiral diols, emerged as straightforward atom-economical methods for producing highly valuable esters.Asymmetric hydrogenation vinyl bis(boronic) can be a complementary approach to synthesizing these products.Additionally, borofunctionalization alkenes or alkynes represents another effective strategy constructing scaffolds.A recent innovation involves migratory coupling reactions with gem-diborylalkanes, offering new avenues esters.The latest developements challenges moleculeshis summarized, potential future research directions this prospected.

Language: Английский

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Enantioselective Cobalt-Catalyzed Remote Hydroboration of Alkenylboronates

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 14, 2025

Heteroatomic groups in alkenes typically direct thermodynamically favored chain walking of C═C bonds toward themselves, thereby facilitating C-H bond functionalization near the heteroatoms. We present herein an efficient cobalt-catalyzed contra-thermodynamic remote hydroboration alkenylboronates with pinacolborane to synthesize chiral 1,n-diboronates. This protocol features a broad substrate scope, high functional group tolerance, and excellent enantioselectivity. Mechanistic studies indicate involvement chain-walking process. Gram-scale reactions various product derivatizations further highlight its practicality.

Language: Английский

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Copper-Catalyzed Regioselective Dihydroboration of Alkynes to Construct gem-Diborylalkanes

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: March 20, 2025

We develop herein an efficient copper-catalyzed dihydroboration of alkynes with HBpin to synthesize gem-diborylalkanes. This catalytic process features a broad substrate scope, good functional group tolerance, and excellent regioselectivity. Notably, the gram-scale reaction further product derivatizations demonstrate practicality this protocol. Preliminary mechanistic studies indicate that involves hydroboration alkyne vinylboronate intermediate.

Language: Английский

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Ligand-Controlled Enantioselective Copper-Catalyzed Hydroboration and Ring-Opening Dihydroboration of Arylidenecyclobutanes

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: March 25, 2025

Arylidenecyclobutanes are readily accessible and versatile reagents in synthetic chemistry due to the multifaceted reactivity exhibited by their alkene strained cyclobutane moieties. However, metal-catalyzed enantioselective functionalization of arylidenecyclobutanes, particularly controllable ring-retaining ring-opening reactions, is rarely explored. Considering utility enantioenriched organoboronate compounds, herein we report ligand-controlled copper-catalyzed hydroboration dihydroboration reactions arylidenecyclobutanes that afford chiral α-cyclobutyl benzylboronate 1,5-diboronate compounds with high enantioselectivity when (S)-DTBM-Segphos (S,S)-Ph-BPE employed, respectively. Mechanistic studies reveal process via β-C elimination significantly slower than arylidenecyclopropanes presence CuOAc (S,S)-Ph-BPE. The these two protocols further demonstrated through conducting various stereospecific site-selective transformations organoboron products, including concise synthesis bioactive molecules.

Language: Английский

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