937-16-6

Usage

InChI:InChI=1/C6H5Br2NO2/c1-11-6(10)4-2-3(7)5(8)9-4/h2,9H,1H3

Upstream product

• 1193-62-0 methyl Pyrrole-2-carboxylate 
• 110-86-1 pyridine 
• 67-56-1 methanol 
• 35302-72-8 pyrrol-2-yl trichloromethyl ketone 

Downstream Products

• 1016650-07-9 methyl 4-bromo-5-(4-methoxyphenyl)-1H-pyrrole-2-carboxylate 
• 1016650-06-8 methyl 4-bromo-5-(4-tert-butylphenyl)-1H-pyrrole-2-carboxylate 

Relevant academic research and scientific papers

Selective bromination of pyrrole derivatives, carbazole and aromatic amines with DMSO/HBr under mild conditions

Bromination of pyrrole derivatives, carbazole and aromatic amines using the DMSO/HBr system affords high yields of the corresponding bromo compounds. Temperature control used in the bromination of anilines helped to promote selective formation of mono- or di-brominated products. Simple operation, low toxicity and high selectivity make this a promising new procedure for the bromination of aromatic compounds.

Vanadate-dependent bromoperoxidases from Ascophyllum nodosum in the synthesis of brominated phenols and pyrroles

Bromoperoxidases from the brown alga Ascophyllum nodosum, abbreviated as VBrPO(AnI) and VBrPO(AnII), show 41% sequence homology and differ by a factor of two in the percentage of α-helical secondary structures. Protein monomers organize into homodimers for VBrPO(AnI) and hexamers for VBrPO(AnII). Bromoperoxidase II binds hydrogen peroxide and bromide by approximately one order of magnitude stronger than VBrPO(AnI). In oxidation catalysis, bromoperoxidases I and II turn over hydrogen peroxide and bromide similarly fast, yielding in morpholine-4-ethanesulfonic acid (MES)-buffered aqueous tert-butanol (pH 6.2) molecular bromine as reagent for electrophilic hydrocarbon bromination. Alternative compounds, such as tribromide and hypobromous acid are not sufficiently electrophilic for being directly involved in carbon-bromine bond formation. A decrease in electrophilicity from bromine via hypobromous acid to tribromide correlates in a frontier molecular orbital (FMO) analysis with larger energy gaps between the π-type HOMO of, for example, an alkene and the σ*Br,X-type LUMO of the bromination reagent. By using this approach, the reactivity of substrates and selectivity for carbon-bromine bond formation in reactions mediated by vanadate-dependent bromoperoxidases become predictable, as exemplified by the synthesis of bromopyrroles occurring naturally in marine sponges of the genera Agelas, Acanthella, and Axinella. The Royal Society of Chemistry.

Parameters for bromination of pyrroles in bromoperoxidase-catalyzed oxidations

Ester-, cyano-, and carboxamide-substituted 1H-pyrroles undergo electrophilic aromatic bromination, if treated with hydrogen peroxide and sodium bromide at pH 6.2 and 20 °C. Oxidation of bromide under such conditions is catalyzed by a vanadate(V)-dependent bromoperoxidase, in a substrate/enzyme ratio of 32-63 μmol %. To obtain maximum yields of bromopyrroles (up to 91%) by spending least amount of substrates and catalyst, hydrogen peroxide and sodium bromide have to be added continuously to the enzyme and the 2-acceptor-substituted pyrrole (1.5 mmol) in a solution of morpholine-4- ethanesulfonic acid buffer. This technique was applied to prepare two marine natural products under biomimetic conditions, that is, methyl 4,5-dibromopyrrole-2-carboxylate (from Agelas oroides) and 4,5-dibromopyrrole-2- carboxamide (from Acanthella carteri).

Vanadate(v)-dependent bromoperoxidase immobilized on magnetic beads as reusable catalyst for oxidative bromination

Vanadate(v)-dependent bromoperoxidase I (Ascophyllum nodosum) was immobilized on magnetic micrometre-sized particles in quantitative yields, with up to 40% retention of initial bromoperoxidase (BPO) activity. The immobilized enzyme was stable with a half-life time of about 160 days. It served as reusable catalyst for bromide oxidation with H2O2 in up to 14 consecutive experiments. Reactivity that resulted from enzymatic bromide oxidation was applicable for methyl pyrrole-2-carboxylate conversion into derivatives of naturally occurring compounds (e.g. from Agelas oroides) with product selectivity of up to 75%.

Direct access to marine pyrrole-2-aminoimidazoles, oroidin, and derivatives, via new acyl-1,2-dihydropyridin intermediates

A short synthesis of the C11N5 oroidin derivatives is reported. The key step of the strategy is a one-pot oxidative bromine-mediated addition of protected guanidines to the N-acyl-1,2-dihydropyridines 9a-c. The new N-acyl-1,2-dihydropyridines were prepared directly from pyridine and pyrrole-2-carbonyl chloride by reduction with borohydride reagent in one step.

4,5-Diaryl-1H-pyrrole-2-carboxylates as combretastatin A-4/lamellarin T hybrids: Synthesis and evaluation as anti-mitotic and cytotoxic agents

The 4,5-diarylated-1H-pyrrole-2-carboxylates 3-8 have each been prepared as hybrids of the potent anti-mitotic agent combretastatin A-4 (1) and the similarly active marine alkaloid lamellarin T (2). The key steps involved selective lithium-for-halogen exchange at C5 within the N-PMB protected 4,5-dibromopyrrole 22 and Negishi cross-coupling of the derived zincated species with the relevant aryl iodide. The ensuing 5-aryl-4-bromopyrrole then engaged in Suzuki-Miyaura cross-coupling with the appropriate arylboronic acid to give the 4,5-diarylated pyrroles 4, 6 and 8. TFA-promoted removal of the N-PMB group within these last compounds then gave the N-unsubstituted congeners 3, 5 and 7. Compounds 3-8 have all been evaluated for their anti-mitotic and cytotoxic properties and two of them, 3 and 5, display useful activities although they are less potent than combretastatin A-4. Crown Copyright