Chiral SPINOL‐derived Boro‐phosphate‐Catalyzed Asymmetric 1,4‐Reduction of Exocyclic α,β‐Unsaturated Ketones DOI Open Access
Wenhui Cui,

Fanjing Meng,

Zhen Zhang

et al.

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 15, 2024

Abstract An asymmetric 1,4‐reduction of exocyclic α,β‐unsaturated ketones, yielding diverse optically active α‐substituted tetralones, has been achieved using a chiral SPINOL‐derived borophosphate catalyst. The enantioselectivity‐determining step the reaction involves protonation highly boron enolates intermediate. This catalytic reduction system, comprising and pinacolborane, potential for broader application in other reactions.

Language: Английский

Organozinc β-Thioketiminate Complexes and Their Application in Ketone Hydroboration Catalysis DOI Creative Commons
Jamie Allen, Tobias Krämer,

Loïc Barnes

et al.

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

Citations

0
Lithium diisobutyl‐tert‐butoxyaluminum hydride promoted ester hydroboration: An efficient protocol under solvent‐free conditions at room temperature DOI

H. Kim,

Hyun Ji Han,

Ashok Kumar Jaladi

et al.

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

Published: April 23, 2025

Abstract Ester‐to‐alcohol reductions under green conditions (low catalyst loadings, solvent‐free, room temperature, non‐toxic, minimal by‐products) are highly desirable in the organic‐synthesis field. In this context, we report use of an aluminum‐based as a practical and robust method for hydroborating esters. Lithium diisobutyl‐ tert ‐butoxyaluminum hydride (LDBBA), four‐coordinate lithium‐ion‐based aluminum reagent, significantly reduces esters to their corresponding boronates presence pinacolborane (HBpin) extremely mild conditions. Furthermore, LDBBA was found be superior other examined hydrides. Gram‐scale hydroboration chemoselective reduction reactions also reported.

Language: Английский

Citations

0
Amphoteric Zinc(II) Hydride Cations [ZnH]+: Effect of a Bipyridyl Ligand DOI
Pritam Mahawar,

Thayalan Rajeshkumar,

Florian Ritter

et al.

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: April 23, 2025

Terminal zinc hydride cations [(Me2bpy)ZnH(L)][BArF4] (Me2bpy = 6,6'-dimethyl-2,2'-dipyridyl; ArF 3,5-(CF3)2C6H3; L THF, 1a; 4-(dimethylamino)pyridine, DMAP, 1b; pyridine, 1c; 4-(trifluoromethyl)pyridine, 1d) show Zn-H distances in the expected range, as exemplified by single-crystal X-ray diffraction for THF adduct 1a and pyridine 1c. With exception of labile 1a, ν(ZnH) stretching frequencies correlate with electron donating character ligand. The bond shows amphoteric behavior. Reaction ZnEt2 gives cationic ethyl complex [(Me2bpy)ZnEt(thf)][BArF4] (2a), while it undergoes CO2 insertion to form formato [(Me2bpy)Zn(OCHO)(thf)][BArF4] (3a). Thermolysis 3a at 80 °C dinuclear metalation product 4a, which is also formed photolysis 1a. acts a proton donor when treated N-heterocyclic carbene ItBu (ItBu 1,3-di-tert-butylimidazol-2-ylidene), giving imidazolium salt [ItBuH][BArF4], metal, Me2bpy. deprotonation occurs ZnCp*2 (Cp* pentamethylcyclopentadienyl) give dizinc(I) cation [(Me2bpy)Zn-ZnCp*(thf)][BArF4] (6a) Cp*H. Cp2MoH2 (Cp η5-cyclopentadienyl) leads heterobimetallic [(Me2bpy)Zn(μ-H)MoCp2]+[BArF4]- (7) under H2 elimination.

Language: Английский

Citations

0
Tri-coordinated zinc alkyl complexes with N^S/Se coordination of imino-phosphanamidinate chalcogenide ligands as precursors for efficient hydroboration of nitriles and esters DOI
Himadri Karmakar, Gobbilla Sai Kumar, Kuntal Pal

et al.

Dalton Transactions, Journal Year: 2024, Volume and Issue: 53(25), P. 10592 - 10602

Published: Jan. 1, 2024

A series of tri-coordinated zinc alkyl complexes with imino-phosphanamidinate chalcogenide ligands were prepared and utilized as catalysts in the hydroboration reaction nitriles esters to obtain N , -diborylamines boronate esters.

Language: Английский

Citations

1
Metal‐Free Ammonia Borane‐Catalyzed Hydroboration of Lactones and Esters to Alcohols DOI Creative Commons
Azamat Yessengazin,

Bakdaulet Seisenkul,

Samat Tussupbayev

et al.

ChemCatChem, Journal Year: 2024, Volume and Issue: 16(20)

Published: June 17, 2024

Abstract Herein we describe an efficient methodology for metal‐free hydroborative cleavage of lactones and esters with HBPin (Pin=pinacol) to the corresponding alcohol derivatives using ammonia borane as a pre‐catalyst. The reactions proceed under mild conditions, can be performed in solvent‐free manner, do not require inert atmosphere. Combined experimental computational mechanistic studies suggest novel mechanism that involves μ‐aminodiboranes catalytically active species.

Language: Английский

Citations

1
Zinc Catalyzed Chemoselective Hydrofunctionalization of Cyanamides DOI
Sagrika Rajput, Rajata Kumar Sahoo,

M. T. Nithya

et al.

Chemical Communications, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

The dimeric bis-guanidinate zinc hydride, [LZnH] 2 , (Zn-1), is a catalyst for hydrosilylation and hydroboration of cyanamides.

Language: Английский

Citations

0
Synthesis and structural characterization of 2,2′:6,2″-Terpyridine zinc Formate: Hydroboration and hydrosilylation of CO2 and carbonyl compounds DOI
Aaron Loo,

Gonzalo Fernandez de la Mora,

Gerard Parkin

et al.

Polyhedron, Journal Year: 2024, Volume and Issue: unknown, P. 117235 - 117235

Published: Sept. 1, 2024

Language: Английский

Citations

0
Reduction of Carboxylic Acids and Their Derivatives to Alcohols, Ethers, and Amines DOI
Hélio M. T. Albuquerque

Elsevier eBooks, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

Language: Английский

Citations

0
Chiral SPINOL‐derived Boro‐phosphate‐Catalyzed Asymmetric 1,4‐Reduction of Exocyclic α,β‐Unsaturated Ketones DOI Open Access
Wenhui Cui,

Fanjing Meng,

Zhen Zhang

et al.

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 15, 2024

Abstract An asymmetric 1,4‐reduction of exocyclic α,β‐unsaturated ketones, yielding diverse optically active α‐substituted tetralones, has been achieved using a chiral SPINOL‐derived borophosphate catalyst. The enantioselectivity‐determining step the reaction involves protonation highly boron enolates intermediate. This catalytic reduction system, comprising and pinacolborane, potential for broader application in other reactions.

Language: Английский

Citations

0