Mixed Lithium–Aluminum Hydrides Bearing Ar-Bian Ligands: Reactivity Toward Heteroallenes

Organometallics, Год журнала: 2024, Номер 43(13), С. 1438 - 1446

Опубликована: Июнь 13, 2024

The reactivity of [(dpp-Bian)Al(H)2Li(THF)3] (1) (dpp-Bian = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) and [(ArBIG-Bian)Al(H)2Li(THF)4] (2) (ArBIG-Bian 1,2-bis[(2,6-dibenzhydryl-4-methylphenyl)imino]acenaphthene) toward isocyanates carbodiimides has been investigated. A treatment 1 with tert-buthylisocyanate affords the formimidate derivative [(dpp-Bian)Al(μ2-OC(H)NtBu)2Li(THF)] (3). related [(ArBIG-Bian)Al(μ2-OC(H)NCy)2Li(THF)] (4) [(ArBIG-Bian)Al((μ-OC(H)NPh)Li(THF)3)(OC(H)NPh)] (5) have obtained by reacting 2 cyclohexyl phenylisocyanates, respectively. Cyclohexylcarbodiimide reacts to give corresponding amidinate derivatives [(dpp-Bian)Al(CyNC(H)NCy)(μ-CyNC(H)NCy)Li(THF)2] (6) [(ArBIG-Bian)Al(CyNC(H)NCy)][Li(DME)3] (7). Complexes 3-7 were characterized IR NMR spectroscopy. molecular structures compounds determined single-crystal X-ray analysis. Both serve well as catalysts in hydroboration pinacolborane (HBpin).

Язык: 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, Год журнала: 2022, Номер 2022(39)

Опубликована: Сен. 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.

Язык: Английский

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Reactions of nickel boranyl compounds with pnictogen–carbon triple bonds

RSC Advances, Год журнала: 2023, Номер 13(28), С. 19158 - 19163

Опубликована: Янв. 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

Язык: Английский

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Tropylium tetrafluoroborate promoted hydroboration of nitriles, imines and amides

Green Chemistry, Год журнала: 2022, Номер 24(19), С. 7382 - 7387

Опубликована: Янв. 1, 2022

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

Язык: Английский

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

Dalton Transactions, Год журнала: 2024, Номер 53(9), С. 4041 - 4047

Опубликована: Янв. 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.

Язык: 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, Год журнала: 2024, Номер 56(20), С. 3083 - 3107

Опубликована: Май 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

Язык: Английский

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

Inorganic Chemistry, Год журнала: 2024, Номер 63(41), С. 19332 - 19343

Опубликована: Окт. 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

Язык: Английский

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Hydroboration of imines: intermolecularvs.intramolecular hydride transfer

New Journal of Chemistry, Год журнала: 2023, Номер 47(24), С. 11544 - 11556

Опубликована: Янв. 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 ).

Язык: Английский

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Frustrated Lewis Pair‐Catalyzed Hydroboration of Nitriles: FLP Versus Borenium Catalysis

Advanced Synthesis & Catalysis, Год журнала: 2022, Номер 364(18), С. 3143 - 3148

Опубликована: Июль 28, 2022

Abstract A frustrated Lewis pair‐catalyzed hydroboration of aromatic and aliphatic nitriles was developed. The catalyst provides the primary amines in high yields 77–99% with loading as low 2 mol%. reaction displays functional group tolerance towards esters, amides, nitro groups halides. addition diborylated to ethyl 3‐phenylpropiolate proceeds Z‐selectivity d.r. >99:1 77–90% yield over two steps. mechanism investigated by control computational experiments. magnified image

Язык: 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, Год журнала: 2023, Номер 10(23), С. 5863 - 5869

Опубликована: Янв. 1, 2023

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

Язык: Английский

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