Autopolymerization of 2-bromo-3-methoxythiophene, analysis of reaction products and estimation of polymer structure

Nishimura, Rokuro; Hattori, Yohei; Akazawa, Masako; Kitai, Jun-ichiro; Okude, Shin’ichiro; Sakamoto, Yuki; Yamazoe, Seiji; Yokojima, Satoshi; Nakamura, Shinichiro; Uchida, Kôji

doi:10.1038/s41428-020-00435-1

Cited by 1 publication

(31 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The peak at 1364 cm −1 is attributed to the −CH 3 bending band of the methoxy group, implying that the methoxy group remains in the polymer. This result is consistent with the result of the elemental atomic analysis 33 carried by the authors. The combustion reactions occur instantaneously.…”

Section: Introductionsupporting

confidence: 93%

“…In the previous research, the authors re-examined the selfcombustion of 2Br-3Met molecules 33 experimentally. During the reaction, a considerable amount of CH 3 Br gas was observed, whereas only a little HBr was observed in the experiment; the mass ratio of CH 3 Br/HBr was 1:0.025.…”

Section: Introductionmentioning

confidence: 99%

“…In ESR measurements, carbon radicals were observed, suggesting that in the reaction, a number of Br and CH 3 radicals were detached from monomers or oligomers of 2Br-3Met. Elemental atomic analysis of the polymer 33 was also carried out. The data were consistent with the estimation that 60% of the mass of the polymer consists of a C 5 H 5 OBrS polymer unit (this polymer unit loses neither Br nor CH 3 from the original 2Br-3Me monomer) and 30% of the mass of the polymer consists of C 4 H 2 OS (this polymer unit loses both Br and CH 3 ).…”

Section: Introductionmentioning

confidence: 99%

“…However, it was difficult to identify the essential mechanisms of spontaneous combustion in the previous experiment. 33 This paper reports the theoretical investigations on the mechanism of dimerization and trimerization reactions of 2Br-3Met molecules, which may be the ignition reactions of oligomerization of 2Br-3Met molecules. Two new reaction schemes are presented based on the reaction scheme proposed .…”

Section: Introductionmentioning

confidence: 99%

“…The results of the calculations were compared with the previous experimental results. 33 It was found that the two reaction schemes explain the most dominant and second-dominant reaction pathways.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Spontaneous Combustion of 2-Bromo-3-Methoxythiophene: A Study on Reaction Pathways and Energetics by Quantum Chemical Calculations

et al. 2021

Self Cite

View full text Add to dashboard Cite

Reaction pathways and energetics for the dimerization and trimerization reactions of 2-bromo-3-methoxythiophene (2Br-3Met) molecules are investigated using hybrid density functional theory (DFT) calculations to obtain insight into the oligomerization reaction observed in the spontaneous combustion of pure liquid 2Br-3Met. The calculations show that the carbon−bromine bond in a 2Br-3Met molecule elongates easily, and the trans addition of this C−Br bond to a double bond in the neighboring 2Br-3Met molecule occurs easily at room temperature, reflecting the evaluated activation energy of ΔH a = 12.46 kcal/mol (enthalpy) or ΔG a = 35.68 kcal/ mol (Gibbs free energy, 298.150 K and 1 atm). The formation process of trimers is calculated in a similar way. A model for the explanation of spontaneous combustion is proposed; large oligomers of the 2Br-3Met molecule are produced spontaneously following the initial formation of dimers or trimers. UV−vis spectra and vibration spectra are obtained for related molecular species, which show reasonable agreement with the experimental results.

show abstract

Section: Introductionsupporting

confidence: 93%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations