Photoinduced Borylation for the Synthesis of Organoboron Compounds

Chemical Reviews, Год журнала: 2021, Номер 121(7), С. 3561 - 3597

Опубликована: Фев. 17, 2021

Organoboron compounds have important synthetic value and can be applied in numerous transformations. The development of practical convenient ways to synthesize boronate esters has thus attracted significant interest. Photoinduced borylations originated from stoichiometric reactions alkanes arenes with well-defined metal–boryl complexes. Now, photoredox-initiated borylations, catalyzed by either transition metal or organic photocatalysts, photochemical high efficiency become a burgeoning area research. In this Focus Review, we summarize research on photoinduced especially emphasizing recent developments trends. This includes the borylation arenes, alkanes, aryl/alkyl halides, activated carboxylic acids, amines, alcohols, so based catalysis, metal-free organocatalysis, direct activation. We focus reaction mechanisms involving single-electron transfer, triplet-energy other radical processes.

Язык: Английский

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First-Row d-Block Element-Catalyzed Carbon–Boron Bond Formation and Related Processes

Chemical Reviews, Год журнала: 2021, Номер 121(21), С. 13238 - 13341

Опубликована: Окт. 7, 2021

Organoboron reagents represent a unique class of compounds because their utility in modern synthetic organic chemistry, often affording unprecedented reactivity. The transformation the carbon–boron bond into carbon–X (X = C, N, and O) stereocontrolled fashion has become invaluable medicinal agrochemistry, natural products chemistry as well materials science. Over past decade, first-row d-block transition metals have increasingly widely used catalysts for formation bond, traditionally catalyzed by expensive precious metals. This recent focus on alternative enabled growth fundamental methods organoboron chemistry. review surveys current state-of-the-art use element-based bonds.

Язык: Английский

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Recent Advances in Methylation: A Guide for Selecting Methylation Reagents

Chemistry - A European Journal, Год журнала: 2018, Номер 25(14), С. 3405 - 3439

Опубликована: Окт. 17, 2018

Methylation is a well-known structural modification in organic and medicinal chemistry. This review summarizes recent advances methylation by categorizing specific reagents. The challenges of mono N-methylation aliphatic amines peptides are discussed. will be useful for chemists wanting to select the appropriate reagents Based on large diversity their wide scope, this also broadens perspectives which strategies utilizing particular methylation, resulting an increased flexibility synthetic route planning.

Язык: Английский

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Geminal bis(boron) compounds: Their preparation and synthetic applications

Tetrahedron Letters, Год журнала: 2018, Номер 59(22), С. 2128 - 2140

Опубликована: Апрель 24, 2018

Язык: Английский

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Highly tunable multi-borylation of gem-difluoroalkenes via copper catalysis

Nature Catalysis, Год журнала: 2018, Номер 1(11), С. 860 - 869

Опубликована: Окт. 26, 2018

Язык: Английский

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Direct Synthesis of Multi(boronate) Esters from Alkenes and Alkynes via Hydroboration and Boration Reactions

ACS Catalysis, Год журнала: 2020, Номер 11(1), С. 1 - 18

Опубликована: Дек. 10, 2020

Multi(boronate) esters have been attracting increasing attention as versatile building blocks for the succinct and precise synthesis of complex molecules. However, there are a limited number efficient synthetic procedures available. In this respect, direct multiboration alkenes alkynes is undoubtedly an ideal route their synthesis. During past 30 years, catalytic systems based on transition-metals, organophosphines, bases, even catalyst-free systems, with heat or light irradiation straightforward preparation from developed. different numbers (up to 4) positional relationships adjacent boron moieties were obtained, which summarized discussed herein.

Язык: Английский

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Generation and Application of (Diborylmethyl)zinc(II) Species: Access to Enantioenriched gem‐Diborylalkanes by an Asymmetric Allylic Substitution

Angewandte Chemie International Edition, Год журнала: 2018, Номер 57(39), С. 12930 - 12934

Опубликована: Июль 2, 2018

We report the successful generation of (diborylmethyl)zinc(II) species by transmetallation beteween isolable (diborylmethyl)lithium and zinc(II) halide (X=Br, Cl) their application in synthesis enantioenriched gem-diborylalkanes bearing a stereogenic center at β-position diboryl groups an asymmetric allylic substitution reaction. The reaction has broad substrate scope, various can be obtained good yields with excellent enantioselectivity. Further elaboration provides access to diverse set valuable chiral building blocks.

Язык: Английский

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Catalytic Chemo- and Enantioselective Transformations of gem-Diborylalkanes and (Diborylmethyl)metallic Species

Accounts of Chemical Research, Год журнала: 2021, Номер 54(20), С. 3917 - 3929

Опубликована: Окт. 6, 2021

ConspectusChemo- and stereoselective transformations of polyborylalkanes are powerful efficient methods to access optically active molecules with greater complexity diversity through programmed synthetic design. Among the various polyborylalkanes, gem-diborylalkanes have attracted much attention in organic chemistry as versatile handles. The notable advantage lies their ability generate two key intermediates, α-borylalkyl anions (gem-diborylalkyl) anions. These different intermediates can be applied enantioselective reactions rapidly a diverse set enantioenriched organoboron compounds, which further manipulated chiral molecule libraries via stereospecific C(sp3)–B bond transformations.In this Account, we summarize our recent contributions development catalytic chemo- using nucleophiles, categorized follows: (1) copper-catalyzed coupling electrophiles (2) design synthesis (diborylmethyl)metallic species applications reactions. Since Shibata Endo reported Pd-catalyzed chemoselective Suzuki–Miyaura cross-coupling organohalides 2014, Morken Hall subsequently developed first analogous TADDOL-derived phosphoramidite supporting ligand palladium catalyst. This discovery sparked interest electrophiles. Our initial studies focused on generating (α-borylmethyl)copper by enantiotopic-group-selective transmetalation copper complexes aldimines ketimines afford syn-β-aminoboronate esters excellent enantio- diastereoselectivity. Moreover, allylation that proceeded reaction situ-generated (α-borylalkyl)copper allyl bromides. Mechanistic investigations revealed between complex occurred open transition state rather than closed state, thereby effectively species. We also utilized such (diborylmethyl)silanes (diborylmethyl)zinc halides succeeded developing aryl iodides benzylic 1,1-silylboronate esters, could used for consecutive molecules. In addition, synthesized time isolated (diborylmethyl)lithium zinc(II) utilization bearing center at β-position an iridium-catalyzed allylic substitution process. addition research efforts, include other groups. hope Account will draw community gem-diboryl compounds provide guiding principles future compounds.

Язык: Английский

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α-Borylalkyl radicals: their distinctive reactivity in modern organic synthesis

Chemical Communications, Год журнала: 2019, Номер 56(1), С. 13 - 25

Опубликована: Ноя. 27, 2019

Organoborons are extremely important for synthetic organic chemistry; they can serve as advanced intermediates a variety of transformations. Such well-known transformation involves the loss boron moiety, creating alkyl radicals. Although these originally developed protocols radical generation remain in active use today, recent years their α-boryl carbon-centred radicals have been joined by new array strategies that offer unique reactivity to forge wider diversity organoborons often operate under mild and benign conditions. Herein, we will highlight stability α-borylalkyl remarkably advances order further utilise them C-C C-heteroatom bond formation. Their this purpose has reported over last decade an attempt guide community. Various transition-metal metal-free methods presented, more photoredox approaches discussed, mainly period 2009-2019.

Язык: Английский

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Versatile cobalt-catalyzed regioselective chain-walking double hydroboration of 1,n-dienes to access gem-bis(boryl)alkanes

Nature Communications, Год журнала: 2020, Номер 11(1)

Опубликована: Фев. 7, 2020

Abstract Double hydroboration of dienes is the addition a hydrogen and boryl group to two double bonds diene molecule represents straightforward effective protocol prepare synthetically versatile bis(boryl)alkanes, provided that this reaction occurs selectively. However, can potentially yield several isomeric organoboron products, it still remains challenge control regioselectivity reaction, which allows selective production single product, in particular, for broad scope dienes. By employing readily available cobalt catalyst, here we show yields useful gem -bis(boryl)alkanes with excellent regioselectivity. In addition, encompasses wide range conjugated non-conjugated Furthermore, mechanistic studies indicate cobalt-catalyzed through boryl-directed chain-walking alkenylboronates generated from anti -Markovnikov 1,2-hydroboration 1,n-diene.

Язык: Английский

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