{"title":"Catalytic Activity of Triphenylphosphine for Electrophilic Aromatic Bromination Using N-Bromosuccinimide and Process Safety Evaluation","authors":"Masahiro Hosoya, Kenichi Ishibashi, Takafumi Ohara, Atsunori Mori, Kentaro Okano","doi":"10.1021/acs.oprd.4c00307","DOIUrl":null,"url":null,"abstract":"Electrophilic aromatic bromination using <i>N</i>-bromosuccinimide (NBS) is the most widely used reaction to synthesize highly functionalized aromatic compounds. We encountered catalytic activity of triphenylphosphine for aromatic bromination. This catalytic activity was successfully applied to a wide range of organic solvents and enabled the addition of NBS below the flash point of various organic solvents. Toward the industrial implementation of this bromination, we evaluated the process safety including the reaction heat and thermal decomposition. The analysis revealed that the characteristic behavior of the reaction heat made it difficult to suppress the increase of the internal temperature. However, precise evaluation of the reaction heat suggested the sequential addition of NBS. This procedure suppressed the increase of the internal temperature below 5 °C, which made the industrial implementation of this bromination feasible with process safety.","PeriodicalId":55,"journal":{"name":"Organic Process Research & Development","volume":null,"pages":null},"PeriodicalIF":3.1000,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Organic Process Research & Development","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1021/acs.oprd.4c00307","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, APPLIED","Score":null,"Total":0}
引用次数: 0
Abstract
Electrophilic aromatic bromination using N-bromosuccinimide (NBS) is the most widely used reaction to synthesize highly functionalized aromatic compounds. We encountered catalytic activity of triphenylphosphine for aromatic bromination. This catalytic activity was successfully applied to a wide range of organic solvents and enabled the addition of NBS below the flash point of various organic solvents. Toward the industrial implementation of this bromination, we evaluated the process safety including the reaction heat and thermal decomposition. The analysis revealed that the characteristic behavior of the reaction heat made it difficult to suppress the increase of the internal temperature. However, precise evaluation of the reaction heat suggested the sequential addition of NBS. This procedure suppressed the increase of the internal temperature below 5 °C, which made the industrial implementation of this bromination feasible with process safety.
期刊介绍:
The journal Organic Process Research & Development serves as a communication tool between industrial chemists and chemists working in universities and research institutes. As such, it reports original work from the broad field of industrial process chemistry but also presents academic results that are relevant, or potentially relevant, to industrial applications. Process chemistry is the science that enables the safe, environmentally benign and ultimately economical manufacturing of organic compounds that are required in larger amounts to help address the needs of society. Consequently, the Journal encompasses every aspect of organic chemistry, including all aspects of catalysis, synthetic methodology development and synthetic strategy exploration, but also includes aspects from analytical and solid-state chemistry and chemical engineering, such as work-up tools,process safety, or flow-chemistry. The goal of development and optimization of chemical reactions and processes is their transfer to a larger scale; original work describing such studies and the actual implementation on scale is highly relevant to the journal. However, studies on new developments from either industry, research institutes or academia that have not yet been demonstrated on scale, but where an industrial utility can be expected and where the study has addressed important prerequisites for a scale-up and has given confidence into the reliability and practicality of the chemistry, also serve the mission of OPR&D as a communication tool between the different contributors to the field.