874959-74-7

Usage

Type of compound

Boronic ester derivative

Specific derivative

1,3,2-dioxaborolane derivative

Structure

Four methyl groups and a thienyl group attached to the boron atom

Applications

Organic synthesis, pharmaceuticals, and agrochemicals

Use

Building block for the preparation of various boron-containing compounds

Reactions

Employed in cross-coupling reactions and other transformations

Bond formation

Facilitates the formation of carbon-carbon or carbon-heteroatom bonds

Significance

Valuable tool for the synthesis of complex organic molecules

Upstream product

• 29421-92-9 4-bromo-2-methylthiophene 
• 25015-63-8 4,4,5,5-tetramethyl-[1,3,2]-dioxaboralane 
• 554-14-3 2-Methylthiophene 
• 30153-46-9 methyl 4-bromo-2-methylthiophene 
• 73183-34-3 bis(pinacol)diborane 

Relevant academic research and scientific papers

Iron-catalysed C(sp2)-H borylation enabled by carboxylate activation

Arene C(sp2)-H bond borylation reactions provide rapid and efficient routes to synthetically versatile boronic esters. While iridium catalysts are well established for this reaction, the discovery and development of methods using Earth-abundant alternatives is limited to just a few examples. Applying an in situ catalyst activation method using air-stable and easily handed reagents, the iron-catalysed C(sp2)-H borylation reactions of furans and thiophenes under blue light irradiation have been developed. Key reaction intermediates have been prepared and characterised, and suggest two mechanistic pathways are in action involving both C-H metallation and the formation of an iron boryl species.

Visible Light-Induced Borylation of C-O, C-N, and C-X Bonds

Boronic acids are centrally important functional motifs and synthetic precursors. Visible light-induced borylation may provide access to structurally diverse boronates, but a broadly efficient photocatalytic borylation method that can effect borylation of a wide range of substrates, including strong C-O bonds, remains elusive. Herein, we report a general, metal-free visible light-induced photocatalytic borylation platform that enables borylation of electron-rich derivatives of phenols and anilines, chloroarenes, as well as other haloarenes. The reaction exhibits excellent functional group tolerance, as demonstrated by the borylation of a range of structurally complex substrates. Remarkably, the reaction is catalyzed by phenothiazine, a simple organic photocatalyst with MW 200 that mediates the previously unachievable visible light-induced single electron reduction of phenol derivatives with reduction potentials as negative as approximately - 3 V versus SCE by a proton-coupled electron transfer mechanism. Mechanistic studies point to the crucial role of the photocatalyst-base interaction.

Efficient Rh-catalyzed C-H borylation of arene derivatives under photochemical conditions

Photocatalysis allows innovations in organic synthesis. Among the various catalytic reactions, CH-functionalizations offer valuable possibilities for the refinement of easily available building blocks. In this respect, catalytic borylation is of interest, too. So far, most of the catalytic borylation reactions are performed under thermal conditions at comparably high temperatures. Here, we describe a new synthetic route for efficient borylation reactions of arenes using a photocatalytic pathway. This novel approach allows the synthesis of a broad variety of borylated arenes and heteroarenes under mild conditions. Applying trans-[Rh(PMe3)2(CO)Cl] as an active photocatalyst and HBPin as an boron source, we achieved high TON. A catalytic cycle that relies on a Rh(i)-Rh(iii) interconversion is proposed.

Pyridopyrimidines used as Plk1 (polo-like kinase) inhibitors

The invention relates to pyridopyrimidinone compounds according to formula (I), wherein the substituents and symbols are as defined in the description. The compounds are inhibitors of Plk1.

PIPERAZINE DERIVATIVES USEFUL FOR THE TREATMENT OF GASTROINTESTINAL DISORDERS

The invention provides compounds of formula (I) or pharmaceutically acceptable salts thereof, wherein Ra, Rb, Rc, Rd, Re, Rf and Y are as defined in the specification. The compounds are partial or full agonists at the growth hormone secretagogue (GHS) receptors . Pharmaceutical compositions comprising the compounds, methods of preparing the compounds, uses of the compounds and methods involving the compounds are also provided.