Highly efficient biphasic ozonolysis of alkenes using a high-throughput film-shear flow reactor

详细信息    查看全文

• 作者：Alexander J. Kendall ; Justin T. Barry ; Daniel T. Seidenkranz ; Ajay Ryerson ; Colin Hiatt ; Chase A. Salazar ; Dillon J. Bryant ; David R. Tyler ; ^{dtyler@uoregon.edu" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Ozonolysis ; Flow chemistry ; Secondary ozonide ; Carbonyl oxide ; Film-shear reactor
• 刊名：Tetrahedron Letters
• 出版年：2016
• 出版时间：23 March 2016
• 年：2016
• 卷：57
• 期：12
• 页码：1342-1345
• 全文大小：2174 K

文摘

A new method for ozonolysis of alkenes using a continuous flow film-shear reactor was developed. The reactor uses a shearing microfluidic mixing chamber to provide biphasic mixing of an organic phase and aqueous phase with ozone gas. The H₂O acts as an in situ reducing agent for the carbonyl oxide intermediate, providing ketones and aldehydes directly from the reaction mixture. Flow rates of up to 1.0 mmol/min (alkene) with an ozone reaction efficiency of >70% were achieved. Aryl conjugated olefins reacted to form carbonyl species in good yields on a multi-gram scale; however, alkyl olefins reacted with ozone to predominantly form secondary ozonides. The discrepancy in product distributions between alkyl and aryl olefins likely originates from the electronic stability of the carbonyl oxide intermediate, which is longer lived for aryl derivatives due to conjugation.