Synlett 2019; 30(13): 1597-1601
DOI: 10.1055/s-0037-1611881
letter
© Georg Thieme Verlag Stuttgart · New York

Iron-Catalyzed Direct Transformation of Benzylic Amines into Carbonyl Compounds in Water

Maki Minakawa
Department of Applied Chemistry, Chemical Engineering and Biochemical Engineering, Yamagata University, 4-3-16, Jonan, Yonezawa, Yamagata 992-8510, Japan   Email: minakawa@yz.yamagata-u.ac.jp
,
Takashi Sasaki
› Author Affiliations
This research was partially supported by the Asahi Glass Foundation, and Yamagata University Gender Equality Office.
Further Information

Publication History

Received: 18 May 2019

Accepted after revision: 17 June 2019

Publication Date:
12 July 2019 (online)


Abstract

Fe-catalyzed direct transformation of benzylic amines into carbonyl compounds was performed in H2O. The reaction of benzylic amines with formaldehyde in the presence of FeCl3·6H2O in H2O afforded the corresponding carbonyl compounds (80 °C to reflux conditions; 14 examples, up to 94% yield). O18-labeling experiments indicated that the O atom in the generated carbonyl is derived from H2O.

Supporting Information

 
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  • 7 0.6 M aq HCl. The concentration was calculated for 3.0 mol equiv of HCl formed from FeCl3·6H2O (20 mol% based on amine).
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