B–N/B–H Transborylation: borane-catalysed nitrile hydroboration

Beilstein Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 18, P. 1332 - 1337

Published: Sept. 26, 2022

The reduction of nitriles to primary amines is a useful transformation in organic synthesis, however, it often relies upon stoichiometric reagents or transition-metal catalysis. Herein, borane-catalysed hydroboration give reported. Good yields (48-95%) and chemoselectivity (e.g., ester, nitro, sulfone) were observed. DFT calculations mechanistic studies support the proposal double B-N/B-H transborylation mechanism.

Language: Английский

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Reactions of nickel boranyl compounds with pnictogen–carbon triple bonds

RSC Advances, Journal Year: 2023, Volume and Issue: 13(28), P. 19158 - 19163

Published: Jan. 1, 2023

The catalytic conversion of unsaturated small molecules such as nitriles into reduced products is interest for the production fine chemicals. In this vein, metal-ligand cooperativity has been leveraged to promote reactivity, often conferring stability bound substrate - a balancing act that may offer activation at cost turnover efficiency. This report describes reactivity [(diphosphine)Ni] compound with pnictogen carbon triple bonds (R-C[triple bond, length m-dash]E; E = N, P), where diphosphine contains two pendant borane groups. For cooperative nitrile coordination observed afford {Ni}2 complexes displaying B-N interactions, whereas P, B-P interactions are absent. work additionally outlines structure-activity relationship uses dihydroboration model reaction unveil effect SCS stabilization, employing 0, 1, or 2 Lewis acid

Language: Английский

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Aluminium‐Catalyzed Selective Reduction of Heteroallenes Through Hydroboration: Amide/Thioamide/Selenoamide Bond Construction and C=X (X=O, S, Se) Bond Activation**

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(39)

Published: Sept. 12, 2022

Abstract An unprecedented conjugated bis‐guanidinate (CBG) stabilized aluminium dihydride, [LAlH 2 ; (L={(ArNH)(ArN)−C=N−C=(NAr)(NHAr)}; Ar=2,6‐Et ‐C 6 H 3 )] ( I ) catalyzed chemoselective hydroboration of heteroallenes such as carbodiimide (CDI)s, isocyanates, isothiocyanates, and isoselenocyanates is reported. A wide range heteroallenes, including electron‐donating withdrawing groups, experience to obtain selectively N‐boryl amide, N‐borylaminal, methyl amine products. More importantly, a single sustainable molecular aluminium‐based catalyst effectively catalyzes CDIs, into formamidines, formamides, thioformamides, selenoformamides, respectively. Further, heteroallene substrates undergo hydrodeoxygenation (HDO), hydrodesulfurization (HDS), hydrodeselenization (HDSe) reactions leading amines. In addition, series control kinetic experiments indicate that the hydride species are essential for all partial complete reduction steps breaking C=X (X=O, S, Se) bonds in heteroallenes.

Language: Английский

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Tropylium tetrafluoroborate promoted hydroboration of nitriles, imines and amides

Green Chemistry, Journal Year: 2022, Volume and Issue: 24(19), P. 7382 - 7387

Published: Jan. 1, 2022

A new organocatalytic approach to reduce nitriles, imines or amides with pinacolborane amines is reported.

Language: Английский

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Iron complexes supported by silyl-NHC chelate ligands: synthesis and use for double hydroboration of nitriles

Dalton Transactions, Journal Year: 2024, Volume and Issue: 53(9), P. 4041 - 4047

Published: Jan. 1, 2024

Iron complexes with newly designed silyl-NHC bidentate ligands showed high performance in the catalytic double hydroboration of nitriles to produce N , -bis(boryl)amines.

Language: Английский

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Recent Advances in Ligand-Controlled Regio- or Stereodivergent Transition-Metal-Catalyzed Hydroelementation (H[E]) (E = H, B, Si, Ge) of C–C Unsaturated Systems

Synthesis, Journal Year: 2024, Volume and Issue: 56(20), P. 3083 - 3107

Published: May 31, 2024

Abstract Reductive functionalization of C–C unsaturated systems, including alkenes and alkynes, with a range hydroelements (H[E]) is one the most fundamental highly practical methods for synthesis functionalized hydrocarbons. Since resultant hydrocarbon products have strong applicability as synthetic intermediates, numerous homogeneous organo(metallic) catalysts been intensively utilized to date reductive reactions. In particular, well-defined transition-metal-based capable controlling regio- or stereoselectivity product by harnessing addition H[E] (E = H, B, Si, Ge) into Cα–Cβ bonds drawn special attention. this review, we describe recent examples transition-metal catalytic systems (M Fe, Co, Rh, Pd, Ni) stereodivergent hydroelementation reactions (conjugated) alkenes, allenes give pair isomeric in high selectivities from same starting compounds simply variation ligand. Mechanistic aspects ligand-controlled selectivity divergence are discussed detail on basis experimental observations and/or computational insights. 1 Introduction 2 Hydroelementation Alkenes Alkynes 3 Conjugated Dienes Diynes 4 Allenes 5 Summary Outlook

Language: Английский

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Alkylaluminum Complexes Featuring Bridged Bis-Formylfluorenimide Ligands for Hydroboration of Aldehyde, Ketone, and Imines

Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 63(41), P. 19332 - 19343

Published: Oct. 3, 2024

Three bis-formylfluorenimide ligands with different bridging groups were designed and synthesized, leading to the successful preparation of six novel alkylaluminum complexes through their reaction reagents (AlMe

Language: Английский

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Hydroboration of imines: intermolecularvs.intramolecular hydride transfer

New Journal of Chemistry, Journal Year: 2023, Volume and Issue: 47(24), P. 11544 - 11556

Published: Jan. 1, 2023

We performed a detailed experimental and theoretical analysis of the 1,3-hydride shift in imine–BH 3 adducts, which represents crucial step formation mono-aminoboranes (R 2 N–BH ).

Language: Английский

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Generation and application of carbodiimide anions: efficient construction of 2-aminopyrimidines via a cascade [4 + 2] annulation/aromatization sequence

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(23), P. 5863 - 5869

Published: Jan. 1, 2023

This work disclosed an unprecedented carbodiimide anion participated cascade [4 + 2] annulation/aromatization reaction, affording efficient method for synthesizing 2-aminopyrimidines.

Language: Английский

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Pt(PPh3)4 and Pt(PPh3)4@IL catalyzed hydroboration of ketones

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: Nov. 19, 2023

An efficient method for the reduction of various ketones via [Pt(PPh3)4]-catalyzed hydroboration with HBpin has been successfully developed first time. The protocol is suitable symmetrical and unsymmetrical derivatives possessing electron donating or withdrawing functional groups. O-borylated products were easily converted to 2° alcohols hydrolysis high isolated yields. According low-temperature NMR spectroscopy, a reaction mechanism was proposed. Additionally, effective immobilization catalyst in ionic liquid [BMIM][NTf2] applied increase productivity process by carrying out reactions under repetitive batch mode, obtaining higher TON values limiting amount expensive Pt used. stability almost neglectable leaching confirmed ICP-MS analysis extracted mixture. A simple separation extraction n-heptane, immobilization, commercial availability complex, make this an attractive ketones.

Language: Английский

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