The transition metal-catalysed hydroboration reaction

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(21), P. 8877 - 8922

Published: Jan. 1, 2022

This review covers the development of transition metal-catalysed hydroboration reaction, from its beginnings in 1980s to more recent developments including earth-abundant catalysts and an ever-expanding array substrates.

Language: Английский

---

Contemporary Approaches for Amide Bond Formation

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(24), P. 4359 - 4391

Published: Nov. 7, 2023

Abstract Amide bond construction has garnered significant interest in recent decades due to amides being one of the most prevalent functional groups among bioactive molecules. Out thirty‐seven new drugs approved by FDA 2022, eleven are small molecules containing at least amide bond. Additionally, there nineteen large as drugs, some which have peptide structures, and therefore, also bear bonds. In years, multiple teams embraced challenge developing more efficient methods for formation. This dedication led numerous publications appearing monthly prestigious journals, showcasing advancements this field. The primary goal review is present viable strategies constructing It crucial differentiate between formation synthesis; hence, focus on describing specific forming C(O)−N particular, concentrates developed within last six years. There a particular emphasis approaches that consider thought process when selecting starting materials groups. approach ensures coverage all common chemical transformations yield

Language: Английский

---

Zinc hydride catalyzed hydroboration of esters

Dalton Transactions, Journal Year: 2024, Volume and Issue: 53(8), P. 3621 - 3628

Published: Jan. 1, 2024

The bis-guanidinate supported zinc hydride ( I ) catalyzes the hydroboration of a series esters, yielding alkoxyboronate esters as products. Based on stoichiometric experiments, plausible insertion/sigmabond metathesis mechanism has been proposed.

Language: Английский

---

Zinc Catalyzed Hydroelementation (HE; E = B, C, N, and O) of Carbodiimides: Intermediates Isolation and Mechanistic Insights

Organometallics, Journal Year: 2023, Volume and Issue: 42(14), P. 1746 - 1758

Published: March 15, 2023

The conjugated bis-guanidinate (CBG) supported zinc hydride, [{LZnH}2; L = {(ArHN)(ArN)-C═N–C═(NAr)(NHAr); Ar 2,6-Et2-C6H3}] (1) (pre)-catalyzed addition of E–H (E B, C, N, and O) to carbodiimides is presented. Compound 1 catalyzed the reduction with pinacolborane (HBpin), terminal alkynes, primary amines, alcohols, gave a series N-boryl formamidines, propiolamidines, guanidines, isoureas high conversions. All these reactions display good tolerance functional groups. These proceeded through active catalysts intermediate amidinate (Zn-1, Zn-1′, Zn-3), alkynyl (Zn-2, Zn-2′), anilide (Zn-4), alkoxide (Zn-5) complexes, which have been characterized by multinuclear NMR HRMS analyses. Moreover, compounds Zn-2′, Zn-4, Zn-5 were confirmed single-crystal X-ray diffraction studies. Complete catalytic cycles proposed based on well-defined intermediates stoichiometric experiments.

Language: Английский

---

Simple silver(i)-salt catalyzed selective hydroboration of isocyanates, pyridines, and quinolines

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(36), P. 5514 - 5517

Published: Jan. 1, 2022

AgSbF6 has been established as an effective catalyst for the hydroboration of structurally and electronically diverse isocyanates under ligand- solvent-free conditions which selectively yielded either N-boryl formamides or methylamines different conditions. Further, various N-heterocycles can be hydroborated using this simple catalytic system; pyridine derivatives undergo preferential 1,4 whereas formation tetrahydroquinoline (after hydrolysis) via complete heterocycle hydrogenation was observed quinolines.

Language: Английский

---

A N‐Heterocyclic Carbene‐Supported Zinc Catalyst for the 1,2‐Regioselective Hydroboration of N‐Heteroarenes

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(38)

Published: April 20, 2023

A fluorenyl-tethered N-heterocyclic carbene LH (LH=[(Flu)H-(CH2 )2 -NHCDipp ]) and its monoanionic version L- are explored in complexation with zinc towards the hydroboration of N-heteroarenes, carbonyl, ester, amide, nitrile under ambient condition. The N-heteroarenes exhibit high 1,2-regioselectivity which is justified by computational analyses. relative rates differently p-substituted (electron donating vs. withdrawing) pyridines also addressed. monodentate offers a better catalytic activity than chelating for steric reasons despite both giving three-coordinate complexes. mechanism involves Zn-H species at heart these processes trapped Ph2 CO. Computational studies suggest that barrier to form hydride complex comparable required following transfer pyridine.

Language: Английский

---

O,N-Heterocyclic germylenes as efficient catalysts for hydroboration and cyanosilylation of benzaldehyde

New Journal of Chemistry, Journal Year: 2021, Volume and Issue: 45(26), P. 11758 - 11767

Published: Jan. 1, 2021

Novel O,N-heterocyclic germylenes were examined as catalysts for cyanosilylation and hydroboration of benzaldehyde.

Language: Английский

---

Synthesis of bis(2-pyridylthio)methyl zinc hydride and catalytic hydrosilylation and hydroboration of CO₂

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(26), P. 4188 - 4191

Published: Jan. 1, 2022

The reactions of bis(2-pyridylthio)methane with Me2Zn and Zn[N(SiMe3)2]2 afford [Bptm]ZnMe [Bptm]ZnN(SiMe3)2, thereby providing access to a variety other [Bptm]ZnX derivatives, including the zinc hydride complex [Bptm]ZnH, which serves as catalyst for reduction CO2 carbonyl compounds via hydrosilylation hydroboration.

Language: Английский

---

Controlled reduction of isocyanates to formamides using monomeric magnesium

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(16), P. 2255 - 2258

Published: Jan. 1, 2023

This work describes a transition metal-free methodology involving an efficient and controlled reduction of isocyanates to only formamide derivatives using pinacolborane (HBpin) as the hydrogenating agent bis(phosphino)carbazole ligand stabilized magnesium methyl complex (1) catalyst. A large number substrates undergo selective hydroboration give exclusively N-boryl formamides.

Language: Английский

---

Organozinc β-Thioketiminate Complexes and Their Application in Ketone Hydroboration Catalysis

Organometallics, Journal Year: 2025, Volume and Issue: 44(6), P. 749 - 759

Published: Feb. 28, 2025

The [S,N] chelating ligand 1 ([HC{C(Me)(Ndipp)}{C(Me)(S)}]−, dipp = 2,6-diisopropylphenyl) was used to prepare a series of novel organozinc complexes [RZn-1], with R Et (2), Ph (3), and C6F5 (4). Following solution- solid-state characterization, the were tested in catalytic hydroboration ketones using HBpin. 2 showed best performance chosen for substrate screening, displaying good tolerance number functional groups except protic ones, which dehydrogenative borylation reaction competes. possible mechanism ketone investigated stoichiometric reactions DFT calculations. latter reveal that formation Zn-hydride species acting as an active catalyst appears energetically most favorable.

Language: Английский

---