140907-23-9

Basic information

• Product Name: 2-Propynoic acid, 3-bromo-, 1,1-dimethylethyl ester
• Synonyms: tert-butyl 3-bromopropiolate
• CAS NO: 140907-23-9
• Molecular Formula: C7H9BrO2
• Molecular Weight: 205.051
• Mol File: 140907-23-9.mol
• Article Data: 5

Chemical Properties

• CAS DataBase Reference: 2-Propynoic acid, 3-bromo-, 1,1-dimethylethyl ester(CAS DataBase Reference)
• NIST Chemistry Reference: 2-Propynoic acid, 3-bromo-, 1,1-dimethylethyl ester(140907-23-9)
• EPA Substance Registry System: 2-Propynoic acid, 3-bromo-, 1,1-dimethylethyl ester(140907-23-9)

Safety Data

• Hazardous Substances Data: 140907-23-9(Hazardous Substances Data)

Upstream product

• 13831-03-3 tert-butyl prop-2-ynoate 

Downstream Products

• 1324008-91-4 tert-butyl 4-bromo-5-iodo-1-(4-methoxyphenyl)-1H-pyrazole-3-carboxylate 
• 1324008-86-7 tert-butyl 3-bromo-5-iodo-1-(4-methoxyphenyl)-1H-pyrazole-4-carboxylate 

Relevant articles and documents

Facile access to 3,5-dihalogenated pyrazoles by sydnone cycloaddition and their versatile functionalization by Pd-catalyzed cross-coupling processes

The 1,3-dipolar cycloaddition of diversely N-substituted 4-iodosydnones with 3-halopropiolates produces easily separable mixtures of dihalogenated pyrazolylcarboxylic esters at a preparative scale level, with the 3,5-dihalogenopyrazole regioisomers always predominating. Further decarboxylation of the major isomers provided the corresponding 3,5-dihalogenopyrazoles with a free C-4 position. These were found to be valuable scaffolds for the elaboration of unsymmetrically 1,3,5-trisubstituted pyrazole derivatives by site-selective Pd-catalyzed cross-coupling reactions. Notably, the flexible and site-selective introduction of different (hetero)aryl, vinyl, or alkyl substituents at the C-5 and C-3 positions of the pyrazole core could be achieved through sequential Suzuki-type reactions with various boron compounds. Copyright

Ru(II)-mediated synthesis and bioactivity evaluation of 1,4,5-trisubstituted N-phthalimido protected 5-bromo-1,2,3-triazolic amino acid

Background: In spite of significant progress made toward the synthesis of triazole amino acids as structural scaffolds of peptides and leading structures of new drugs, a need still exists for effective methods of trisubstituted triazole amino acid synthesis. Methods: A protocol based on ruthenium(II)-catalyzed alkyne-azide cycloaddition (RuAAC) was developed to synthesize 5-bromo-1,4,5-trisubstituted 1,2,3-triazole-based amino acid – tert-butyl 5-bromo-1-(2-(1,3-dioxo-2,3dihydro-1H-isoindol-2-yl)ethyl]-1H-1,2,3-triazole-4-carboxylate (5Br-TzlAA). Two other disubstituted regioisomers, 1,4- and 1,5-TzlAA, were also synthesized to evaluate the influence of the 5-bromo substituent for triazole ring bioactivity. Results: Under optimal conditions, 5Br-TzlAA was synthesized within 1 h with 93% yield. NMR confirmed the structure of 5Br-TzlAA and showed regioselectivity of the RuAAC reaction. None of the TzlAAs were cytotoxic for the human cell lines investigated and showed a small pro-proliferatory effect at the highest concentrations (50-100 μg/mL) studied. A small anti-proliferative effect was visible for 1,4-TzlAA. Conclusion: A simple and effective protocol for the synthesis of 5-bromo-1,4,5-trisubstituted TzlAA (5Br-TzlAA) was developed. Bioassay results show that N-phthalimido modifying the TzlAAs are well tolerated by human cells and may be used as leading or scaffold structures to design new biologically active molecules.

Preparation of 3-bromopropiolic esters:methyl and tert-butyl 3-bromopropiolates

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