Synlett 2020; 31(09): 866-870
DOI: 10.1055/s-0039-1691601
letter
© Georg Thieme Verlag Stuttgart · New York

Nucleophilic Addition to Nitrones Using a Flow Microreactor

Yukihiro Arakawa
a  Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan
,
Shun Ueta
a  Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan
,
Takuma Okamoto
a  Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan
,
Keiji Minagawa
a  Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan
b  Institute of Liberal Arts and Sciences, Tokushima University, Minamijosanjima, Tokushima 770-8502, Japan   Email: imada@tokushima-u.ac.jp
,
Yasushi Imada
a  Department of Applied Chemistry, Tokushima University, Minamijosanjima, Tokushima 770-8506, Japan
› Author Affiliations
This work was supported by the Research Clusters program of Tokushima University (no. 1802001).
Further Information

Publication History

Received: 16 January 2020

Accepted after revision: 30 January 2020

Publication Date:
18 February 2020 (online)


Abstract

Nucleophilic addition reactions of soft carbon nucleophiles to nitrones in a flow microreactor are reported for the first time. Under microflow conditions at 30 to 0 °C, a range of nitrones can be efficiently transformed into the corresponding oxyiminium ions by reaction with either acyl halides or trialkylsilyl triflates. These can subsequently undergo the addition of nucleophiles including allyltributylstannane, ketene methyl tert-butyldimethylsilyl acetal, and N-silyl ketene imines to afford the corresponding adducts in high yields; such reactions at a similar temperature under batch conditions resulted in lower yields because of undesired side reactions.

Supporting Information

 
  • References and Notes

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