402503-13-3

Usage

Uses

Used in Organic Chemistry:
2-(Benzofuran-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane is used as a reagent in various organic synthesis processes for its ability to participate in coupled reactions and palladium-catalyzed cross-couplings. Its unique structure allows for the formation of new carbon-carbon and carbon-heteroatom bonds, which are crucial in the synthesis of complex organic molecules.
Used in Pharmaceutical Synthesis:
In the pharmaceutical industry, 2-(Benzofuran-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane is employed as an intermediate or a building block in the synthesis of various drugs and biologically active compounds. Its reactivity and structural features enable the creation of diverse molecular frameworks that can be further modified to achieve the desired pharmacological properties.
Used in the Synthesis of Biologically Active Compounds:
2-(Benzofuran-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane is also used in the synthesis of biologically active compounds, such as agrochemicals and materials with potential applications in biotechnology. Its versatility in chemical reactions allows for the development of novel molecules with specific biological activities, contributing to advancements in these fields.

Upstream product

• 63361-60-4 2-chlorobenzo[b]furan 
• 73183-34-3 bis(pinacol)diborane 
• 271-89-6 1-benzofurane 
• 25015-63-8 4,4,5,5-tetramethyl-[1,3,2]-dioxaboralane 
• 76-09-5 2,3-dimethyl-2,3-butane diol 
• 41717-28-6 2-benzofuroyl chloride 
• 496-16-2 2.3-dihydrobenzofuran 
• 1195-66-0 2-methoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane 
• 98437-24-2 benzofuran-2-boronic acid 
• 27124-07-8 2-deuteriobenzofuran 

Downstream Products

• 1646-27-1 methyl benzofuran-2-carboxylate 
• 41014-29-3 2,2'-bibenzofuranyl 
• 69626-75-1 2-iodobenzofuran 
• 38221-19-1 hydroxybenzofuran 
• 41013-94-9 4-(1-benzofuran-2-yl)benzonitrile 
• 885273-16-5 2-(5'-indoyl)benzofuran 
• 121668-44-8 2-(2-benzofuranyl)-benzonitrile 
• 4265-25-2 2-methylbenzofuran 
• 1241836-03-2 (3,6-bis[5-(benzofuran-2-yl)-thiophen-2-yl]-2,5-bis(2-ethylhexyl)pyrrolo[3,4-c]pyrrole-1,4-dione) 
• 1430728-27-0 N-(3-(benzofuran-2-yl)-5-nitrophenyl)acetamide 

Relevant academic research and scientific papers

Insights into Activation of Cobalt Pre-Catalysts for C(sp2)?H Functionalization

The activation of readily prepared, air-stable cobalt(II) bis(carboxylate) pre-catalysts for the functionalization of C(sp2)?H bonds has been systematically studied. With the pyridine bis(phosphine) chelate, iPrPNP, treatment of 1-(O2CtBu)2 with either B2Pin2 or HBPin generated cobalt boryl products. With the former, reduction to (iPrPNP)CoIBPin was observed while with the latter, oxidation to the cobalt(III) dihydride boryl, trans-(iPrPNP)Co(H)2BPin occurred. The catalytically inactive cobalt complex, Co[PinB(O2CtBu)2]2, accompanied formation of the cobalt-boryl products in both cases. These results demonstrate that the pre-catalyst activation from cobalt(II) bis(carboxylates), although effective and utilizes an air-stable precursor, is less efficient than activation of cobalt(I) alkyl or cobalt(III) dihydride boryl complexes, which are quantitatively converted to the catalytically relevant cobalt(I) boryl. Related cobalt(III) dihydride silyl and cobalt(I) silyl complexes were also synthesized from treatment of trans-(iPrPNP)Co(H)2BPin and (iPrPNP)CoPh with HSi(OEt)3, respectively. No catalytic silylation of arenes was observed with either complex likely due to the kinetic preference for reversible C?H reductive elimination rather than product- forming C?Si bond formation from cobalt(III). Syntheses of the cobalt(II) bis(carboxylate) and cobalt(I) alkyl of iPrPONOP, a pincer where the methylene spacers have been replaced by oxygen atoms, were unsuccessful due to deleterious P?O bond cleavage of the pincer. Despite their structural similarity, the rich catalytic chemistry of iPrPNP was not translated to iPrPONOP due to the inability to access stable cobalt precursors as a result of ligand decomposition via P?O bond cleavage.

Mono-Phosphine Metal-Organic Framework-Supported Cobalt Catalyst for Efficient Borylation Reactions

We report a metal-organic framework (MOF) supported monoligated phosphine-cobalt complex, which is an active heterogeneous catalyst for aromatic C?H borylation and alkene hydroboration. The mono(phosphine)-Co catalyst (MOF?P?Co) was prepared by metalation of a porous triarylphosphine-functionalized MOF (MOF?P) with CoCl2 followed by activation with NaEt3BH. The MOF catalyst has a broad substrate scope with excellent functional group tolerance to afford arene- and alkyl-boronate esters in excellent yields and selectivity. MOF?P?Co gave a turnover number (TON) of 30,000 and could be recycled and reused at least 13 times in arene C?H borylation. Importantly, the attempt to prepare the homogeneous control (Ph3P?Co) using triphenylphosphine was unsuccessful due to the facile disproportionation reactions or intermolecular ligand exchanges in the solution. In contrast, the site isolation of the active mono(phosphine)-Co species within the MOF affords the robust and coordinatively unsaturated metal complexes, allowing to explore their catalytic properties and the reaction mechanism.

METHOD FOR SYNTHESIZING BORONATE ESTER COMPOUND, SODIUM SALT OF BORONATE ESTER COMPOUND, AND METHOD FOR SYNTHESIZING THE SAME

An object is to establish a technology with which a boronate ester compound can be easily and efficiently synthesized at a low cost with a small number of steps without the need for a complex chemical method and reagents that need to be carefully handled. A further object is to establish a sodium salt of a boronate ester compound that is a novel compound and a technology for synthesizing the sodium salt of a boronate ester compound. Provided are a sodium salt of a boronate ester compound and a method for synthesizing a boronate ester compound or a sodium salt of a boronate ester compound that includes reacting, in a reaction solvent, an organic chloride with a dispersion product obtained by dispersing sodium in a dispersion solvent to obtain an organic sodium compound, and reacting the obtained organic sodium compound with a borate ester compound to obtain a boronate ester compound or a sodium salt of a boronate ester compound.

Understanding the Activation of Air-Stable Ir(COD)(Phen)Cl Precatalyst for C-H Borylation of Aromatics and Heteroaromatics

A newly developed robust catalyst [Ir(COD)(Phen)Cl] (A) was used for the C-H borylation of three dozen aromatics and heteroaromatics with excellent yield and selectivity. Activation of the catalyst was identified by the use of catalytic amounts of water, alcohols, etc., when B2pin2 was used in noncoordinating solvents, while for THF catalytic use of HBpin was required. The results were on par with the in situ based expensive system [Ir(OMe)(COD)]2/dtbbpy or Me4Phen.

Remarkably Efficient Iridium Catalysts for Directed C(sp2)-H and C(sp3)-H Borylation of Diverse Classes of Substrates

Here we describe the discovery of a new class of C-H borylation catalysts and their use for regioselective C-H borylation of aromatic, heteroaromatic, and aliphatic systems. The new catalysts have Ir-C(thienyl) or Ir-C(furyl) anionic ligands instead of the diamine-type neutral chelating ligands used in the standard C-H borylation conditions. It is reported that the employment of these newly discovered catalysts show excellent reactivity and ortho-selectivity for diverse classes of aromatic substrates with high isolated yields. Moreover, the catalysts proved to be efficient for a wide number of aliphatic substrates for selective C(sp3)-H bond borylations. Heterocyclic molecules are selectively borylated using the inherently elevated reactivity of the C-H bonds. A number of late-stage C-H functionalization have been described using the same catalysts. Furthermore, we show that one of the catalysts could be used even in open air for the C(sp2)-H and C(sp3)-H borylations enabling the method more general. Preliminary mechanistic studies suggest that the active catalytic intermediate is the Ir(bis)boryl complex, and the attached ligand acts as bidentate ligand. Collectively, this study underlines the discovery of new class of C-H borylation catalysts that should find wide application in the context of C-H functionalization chemistry.

Single-Site Cobalt-Catalyst Ligated with Pyridylimine-Functionalized Metal-Organic Frameworks for Arene and Benzylic Borylation

We report a highly active single-site heterogeneous cobalt-catalyst based on a porous and robust pyridylimine-functionalized metal-organic frameworks (pyrim-MOF) for chemoselective borylation of arene and benzylic C-H bonds. The pyrim-MOF having UiO-68 topology, constructed from zirconium-cluster secondary building units and pyridylimine-functionalized dicarboxylate bridging linkers, was metalated with CoCl2 followed by treatment of NaEt3BH to give the cobalt-functionalized MOF-catalyst (pyrim-MOF-Co). Pyrim-MOF-Co has a broad substrate scope, allowing the C-H borylation of halogen-, alkoxy-, alkyl-substituted arenes as well as heterocyclic ring systems using B2pin2 or HBpin (pin = pinacolate) as the borylating agent to afford the corresponding arene- or alkyl-boronate esters in good yields. Pyrim-MOF-Co gave a turnover number (TON) of up to 2500 and could be recycled and reused at least 9 times. Pyrim-MOF-Co was also significantly more robust and active than its homogeneous control, highlighting the beneficial effect of active-site isolation within the MOF framework that prevents intermolecular decomposition. The experimental and computational studies suggested (pyrim?-)CoI(THF) as the active catalytic species within the MOF, which undergoes a mechanistic pathway of oxidative addition, turnover limiting σ-bond metathesis, followed by reductive elimination to afford the boronate ester.

Ring-Opening Lithiation–Borylation of 2-Trifluoromethyl Oxirane: A Route to Versatile Tertiary Trifluoromethyl Boronic Esters

Stereogenic trifluoromethyl-substituted carbon centers are highly sought-after moieties in pharmaceutical and agrochemical discovery. Here, we show that lithiation–borylation reactions of 2-trifluoromethyl oxirane give densely functionalized and highly versatile trifluoromethyl-substituted α-tertiary boronic esters. The intermediate boronate complexes undergo the desired 1,2-rearrangement of the carbon-based group with complete retentive stereospecificity, a process that was only observed in non-polar solvents in the presence of TESOTf. Although the trifluoromethyl group adversely affects subsequent transformations of the α-boryl group, Zweifel olefinations provide trifluoromethyl-bearing quaternary stereocenters substituted with alkenes, alkynes and ketones.

C(sp2)-H Borylation of Heterocycles by Well-Defined Bis(silylene)pyridine Cobalt(III) Precatalysts: Pincer Modification, C(sp2)-H Activation, and Catalytically Relevant Intermediates

Well-defined bis(silylene)pyridine cobalt(III) precatalysts for C(sp2)-H borylation have been synthesized and applied to the investigation of the mechanism of the catalytic borylation of furans and 2,6-lutidine. Specifically, [(ArSiNSi)CoH3]·NaHBEt3 {ArSiNSi = 2,6-[EtNSi(NtBu)2CAr]2C5H3N, where Ar = C6H5 (1-H3·NaHBEt3) or 4-MeC6H4 (2-H3·NaHBEt3)} and trans-[(ArSiNSi)Co(H)2BPin] {Ar = C6H5 [1-(H)2BPin] or 4-MeC6H4 [2-(H)2BPin], and Pin = pinacolato} were prepared and employed as single-component precatalysts for the C(sp2)-H borylation of 2-methylfuran, benzofuran, and 2,6-lutidine. The cobalt(III) precursors, 2-H3·NaHBEt3 and 2-(H)2BPin, also promoted C(sp2)-H activation of benzofuran, yielding [(ArSiNSi)CoH(Bf)2] {Ar = 4-MeC6H4 [2-H(Bf)2], and Bf = 2-benzofuranyl}. Monitoring the catalytic borylation of 2-methylfuran and 2,6-lutidine by 1H NMR spectroscopy established the trans-dihydride cobalt(III) boryl as the catalyst resting state at low substrate conversions. At higher conversions, two distinct pincer modification pathways were identified, depending on the substrate and the boron source.

Method for efficiently catalyzing selective boronation reaction of five-membered heterocycle

The invention relates to a method for efficiently catalyzing a selective boronation reaction of a five-membered heterocycle. A heterocyclic borate product can be smoothly prepared through convenientlycatalyzing a selective boronation reaction of furan and thiophene derivatives and a cheap and easily available organic boron reagent under a mild condition by a cheap ruthenium metal complex taken asa catalyst. Compared with a reported method, the method of the invention has the obvious advantages of specific reaction selectivity, low catalyst dosage, convenience in operation, no need of addinga reaction solvent and the like, and an efficient and high-selectivity reaction strategy is provided for laboratory preparation or industrial production of the heterocyclic borate product.

Metal-organic frameworks containing nitrogen-donor ligands for efficient catalytic organic transformations

Metal-organic framework (MOFs) compositions based on nitrogen donor-based organic bridging ligands, including ligands based on 1,3-diketimine (NacNac), bipyridines and salicylaldimine, were synthesized and then post-synthetically metalated with metal precursors, such as complexes of first row transition metals. Metal complexes of the organic bridging ligands could also be directly incorporated into the MOFs. The MOFs provide a versatile family of recyclable and reusable single-site solid catalysts for catalyzing a variety of asymmetric organic transformations. The solid catalysts can also be integrated into a flow reactor or a supercritical fluid reactor.