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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Iron- and Cobalt-Catalyzed Asymmetric Hydrofunctionalization of Alkenes and Alkynes

Accounts of Chemical Research, Год журнала: 2021, Номер 54(11), С. 2701 - 2716

Опубликована: Май 20, 2021

ConspectusTransition metal catalyzed asymmetric hydrofunctionalization of readily available unsaturated hydrocarbons presents one the most straightforward and atom-economic protocols to access valuable optically active products. For decades, noble transition catalysts have laid cornerstone in this field, on account their superior reactivity selectivity. In recent years, from an economical sustainable standpoint, first-row, earth-abundant metals received considerable attention, due high natural reserves, affordable costs, low toxicity. Meanwhile, reactions also gained much interest been investigated gradually. However, since chiral ligand libraries for transition-metal catalysis are limited date, development highly enantioselective versions remains a significant challenge.This Account summarizes our efforts developing suitable ligands iron cobalt applications (hydroboration hydrosilylation) alkenes alkynes. design, we envisioned that unsymmetric NNN-tridentate (UNT) scaffolds could promote these transformations with metals. Therefore, several types UNT were designed prepared laboratory, utilizing amino acids as sources. very beginning, oxazoline iminopyridine (OIP) proposed through rational combination nitrogen-containing scaffolds. After systematic survey effects, imine moiety rigid OIP was replaced by conformationally more flexible amine unit, leading construction reactive aminoisopropylpyridine (OAP) ligands. Subsequently, imidazoline (IIP) thiazoline (TIP) altering oxygen atom nitrogen sulfur linkers, respectively. To further expand library, other tridentate containing twisted pincer, anionic, nonrigid backbone synthesized, including iminophenyl oxazolinyl phenylamine (IPOPA) phenyl picolinamide (ImPPA). The efficacy induction has demonstrated sequential alkynes, which exhibit excellent well chemo-, regio-, stereoselectivity broad functional group tolerance. Notably, regio- challenging substrates, such 1,1-disubstituted aryl terminal aliphatic alkenes, achieved. Furthermore, isomerization/hydroboration internal alkynes demonstrates synthetic power catalytic systems. enantioenriched products obtained methodologies be potentially utilized organic synthesis, medicinal chemistry, materials science. We believe continuous field would beneficial catalysis.

Язык: Английский

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Ni-Catalyzed stereoselective difunctionalization of alkynes

Organic Chemistry Frontiers, Год журнала: 2020, Номер 7(23), С. 3941 - 3955

Опубликована: Янв. 1, 2020

We summarize the progress of nickel-catalyzed alkyne difunctionalization reaction for synthesis tri- and tetrasubstituted olefins, with an emphasis on strategy control stereochemistry.

Язык: Английский

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Hydrosilylation and hydroboration in a sustainable manner: from Earth-abundant catalysts to catalyst-free solutions

Green Chemistry, Год журнала: 2020, Номер 22(16), С. 5210 - 5224

Опубликована: Янв. 1, 2020

Hydroelementation enables a facile reduction or functionalization of several unsaturated systems, and thus activation such bonds like B–H Si–H is powerful synthetic tool.

Язык: Английский

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Enantioselective Rhodium-Catalyzed Desymmetric Hydrosilylation of Cyclopropenes

ACS Catalysis, Год журнала: 2019, Номер 9(10), С. 9110 - 9116

Опубликована: Авг. 30, 2019

Catalytic hydrosilylation of alkenes ranks as one the most important academic and industrial synthetic reactions in homogeneous catalysis organosilicon chemistry. In this work, a highly enantioselective Rh-catalyzed desymmetric reaction 1,1-disubstituted cyclopropenes with promotion chiral DTBM-SEGPHOS is described. It allows for straightforward access to potentially valuable compounds bearing carbon quaternary stereocenter high yields good diastereo- enantioselectivities (up >99:1 d.r. >99% ee) 100% atom-efficient manner from readily available starting hydrosilanes.

Язык: Английский

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Stereospecific Si-C coupling and remote control of axial chirality by enantioselective palladium-catalyzed hydrosilylation of maleimides

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

Опубликована: Июнь 9, 2020

Abstract Hydrosilylation of unsaturated carbon-carbon bonds with hydrosilanes is a very important process to access organosilicon compounds and ranks as one the most fundamental reactions in organic chemistry. However, catalytic asymmetric hydrosilylation activated alkenes internal has proven elusive, due competing reduction double bond or isomerization processes. Herein, we report highly enantioselective Si-C coupling by carbonyl-activated using palladium catalyst chiral TADDOL-derived phosphoramidite ligand, which inhibits O-hydrosilylation/olefin reduction. The stereospecific coupling/hydrosilylation maleimides affords series silyl succinimides up 99% yield, >99:1 diastereoselectivity enantioselectivity. high degree stereoselectivity exerts remote control axial chirality, leading functionalized, axially are versatile building blocks. product utility highlighted construction N-heterocycles bearing three stereocenters.

Язык: Английский

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Ligand‐Regulated Regiodivergent Hydrosilylation of Isoprene under Iron Catalysis

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(43), С. 19115 - 19120

Опубликована: Июль 3, 2020

A method for the regiodivergent and stereoselective hydrosilylation of basic industrial feedstock isoprene with unactivated silanes has been developed using earth-abundant iron catalysts. The manipulation regioselectivity relies on fine modification coordination geometry center. While a bidentate pyridine imine ligand promoted formation allylic through 4,1-addition, selectivity 3,4-adduct homoallylic was observed tridentate nitrogen ligand. Experimental studies analysis were carried out to elucidate reaction mechanism factors enabling regioselectivity. This study contributes art control in alkene hydrofunctionalization.

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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Inorganometallics (Transition Metal–Metalloid Complexes) and Catalysis

Chemical Reviews, Год журнала: 2021, Номер 122(3), С. 3996 - 4090

Опубликована: Дек. 30, 2021

While the formation and breaking of transition metal (TM)-carbon bonds plays a pivotal role in catalysis organic compounds, reactivity inorganometallic species, that is, those involving (TM)-metalloid (E) bond, is key importance most conversions metalloid derivatives catalyzed by TM complexes. This Review presents background its development over last 15 years. The results mechanistic studies presented are related to occurrence TM-E TM-H compounds as reactive intermediates catalytic transformations selected metalloids (E = B, Si, Ge, Sn, As, Sb, or Te). illustrates significance inorganometallics following processes: addition metalloid-hydrogen metalloid-metalloid unsaturated compounds; activation functionalization C-H C-X with hydrometalloids bismetalloids; vinylmetalloids, halides, sulfonates; dehydrocoupling hydrometalloids. first on sums up developments methods for synthesis organometalloid their applications advanced part tandem reactions.

Язык: Английский

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Phenanthroline-imine ligands for iron-catalyzed alkene hydrosilylation

Chemical Science, Год журнала: 2022, Номер 13(9), С. 2721 - 2728

Опубликована: Янв. 1, 2022

Iron-catalyzed organic reactions have been attracting increasing research interest but still serious limitations on activity, selectivity, functional group tolerance, and stability relative to those of precious metal catalysts. Progress in this area will require two key developments: new ligands that can impart reactivity iron catalysts elucidation the mechanisms catalysis. Herein, we report development novel 2-imino-9-aryl-1,10-phenanthrolinyl complexes catalyze both

Язык: Английский

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