439813-83-9

Usage

Chemical structure

1-benzyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrrole

Type of compound

Pyrrole derivative

Contains

Benzyl group and boron-containing heterocycle

Application

Building block in organic synthesis

Used in

Formation of complex organic molecules

Fields of application

Medicinal chemistry, material science, and chemical research

Boron-containing group

Useful for various reactions

Specific reaction

Suzuki-Miyaura cross-coupling reactions

Commonly employed in

Synthesis of pharmaceuticals and agrochemicals

Potential use

Development of new drugs and materials

Upstream product

• 18159-13-2 1-benzyl-3-bromo-1H-pyrrole 
• 25015-63-8 4,4,5,5-tetramethyl-[1,3,2]-dioxaboralane 
• 2051-97-0 1-benzyl-1H-pyrrole 
• 100-46-9 benzylamine 
• 439813-69-1 (1,4-dichloro-2-buten-2-yl)boronic acid pinacol ester 

Downstream Products

• 53646-88-1 1-benzyl-3-phenyl-1H-pyrrole 

Relevant academic research and scientific papers

Alkylammoniotrifluoroborate functionalized polystyrenes: Polymeric pre-catalysts for the metal-free borylation of heteroarenes

Three polymeric versions of ansa-N,N-dialkylammoniumtrifluoroborate ambiphilic molecules based on the styrene motif (poly(1-NMe2H+-2-BF3--4-styrene) (P-Me), poly(1-NEt2H+-2-BF3--4-styrene) (P-Et) and poly(1-piperidinyl-H+-2-BF3--4-styrene) (P-Pip)) were synthesized, characterized and tested as heterogeneous pre-catalysts for the borylation of electron-rich heteroarenes. These heterogeneous versions of previously reported pre-catalysts show similar reactivity patterns and represent the first examples of solid-supported FLP metal-free catalysts for the C-H borylation of heteroarenes.

Practical and Scalable Synthesis of Borylated Heterocycles Using Bench-Stable Precursors of Metal-Free Lewis Pair Catalysts

A practical and scalable metal-free catalytic method for the borylation and borylative dearomatization of heteroarenes has been developed. This synthetic method uses inexpensive and conveniently synthesizable bench-stable precatalysts of the form 1-NHR2-2-BF3-C6H4, commercially and synthetically accessible heteroarenes as substrates, and pinacolborane as the borylation reagent. The preparation of several borylated heterocycles on 2 and 50 g scales was achieved under solvent-free conditions without the use of Schlenk techniques or a glovebox. A kilogram-scale borylation of one of the heteroarene substrates was also achieved using this cost-effective green methodology to exemplify the fact that our methodology can be conveniently implemented in fine chemical industries.

PRECATALYSTS AND PROCESS FOR THE METAL-FREE FUNCTIONALIZATION OF SP2 CARBONS USING THE SAME

Precatalysts of formula I and IV, and processes for the functionalization of SP2-carbons using the same are described herein. The precatalysts comprise a fluoroborate salt protected intramolecular frustrated lewis pair (FLP). The precatalysts are bench stable with improved stability towards moisture and/or air. The precatalysts can be used to generate in situ the corresponding FLP catalyst.

Bench-stable frustrated Lewis pair chemistry: Fluoroborate salts as precatalysts for the C-H borylation of heteroarenes

While the organotrifluoroborate group is commonly used as a leaving group in cross-coupling reactions, we now show that their high stability can be used to protect the Lewis acidic moieties of frustrated Lewis pair catalysts. Indeed, the air and moisture-stable trifluoro- and difluoroborate derivatives of bulky (tetramethylpiperidino)benzene are shown to be conveniently converted to their dihydroborane analogue which is known to activate small molecules. An efficient synthesis route to these stable and convenient precatalysts, their deprotection chemistry and their benchtop use for the dehydrogenative borylation of heteroarenes is presented.

PROCESS FOR THE FUNCTIONALIZATION OF SP2-H CARBONS USING FRUSTRATED LEWIS PAIR CATALYSTS

A catalytic process for the metal-free functionalization of sp2-carbons is described herein. The catalytic process is suitable for forming borylated alkenes, arenes and heteroarenes and comprises the use of catalysts comprising a Frustrated Lewis Pair (FLP).

Metal-free catalytic C-H bond activation and borylation of heteroarenes

Transition metal complexes are efficient catalysts for the C-H bond functionalization of heteroarenes to generate useful products for the pharmaceutical and agricultural industries. However, the costly need to remove potentially toxic trace metals from the end products has prompted great interest in developing metal-free catalysts that can mimic metallic systems.We demonstrated that the borane (1-TMP-2-BH2-C6H4)2 (TMP, 2,2,6,6-tetramethylpiperidine) can activate the C-H bonds of heteroarenes and catalyze the borylation of furans, pyrroles, and electron-rich thiophenes. The selectivities complement those observed with most transition metal catalysts reported for this transformation.

Highly efficient monophosphine-based catalyst for the palladium-catalyzed Suzuki-Miyaura reaction of heteroaryl halides and heteroaryl boronic acids and esters

A highly active and efficient catalyst system derived from a palladium precatalyst and monophosphine ligands 1 or 2 for the Suzuki-Miyaura cross-coupling reaction of heteroaryl boronic acids and esters has been developed. This method allows for the preparation of a wide variety of heterobiaryls in good to excellent yields and displays a high level of activity for the coupling of heteroaryl chlorides as well as hindered aryl and heteroaryl halides. Specific factors that govern the efficacy of the transformation for certain heterocyclic motifs were also investigated.

Suzuki coupling reactions in heterocyclic chemistry: Synthesis of 3-substituted pyrrolines and pyrroles

A simple preparation of N-substituted 3-pyrroline boromic esters from primary amines is described. The Suzuki-Miyaura coupling of these heterocycles with aryl halides proceeds in good yields. Alternatively, oxidation with DDQ or MnO2, gives the