Synthesis 2011(21): 3418-3425  
DOI: 10.1055/s-0030-1260257
FEATUREARTICLE
© Georg Thieme Verlag Stuttgart ˙ New York

Practical Preparation Methods for Highly Active Azaadamantane-Nitroxyl-Radical-Type Oxidation Catalysts

Masatoshi Shibuyaa, Yusuke Sasanoa, Masaki Tomizawaa, Toshimasa Hamadab, Masami Kozawac, Noriaki Nagahamac, Yoshiharu Iwabuchi*a
a Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aobayama, Sendai 980-8578, Japan
Fax: +81(22)7956845; e-Mail: iwabuchi@mail.pharm.tohoku.ac.jp;
b Performance Materials Division, Planning & Development Dept., Nissan Chemical Industries, Ltd., 3-7-1 Kanda-Nishiki-cho, Chiyoda-ku, Tokyo 101-0054, Japan
c Synthesis Research Dept., Nissan Chemical Industries, Ltd., 2-10-1 Tsuboi-nishi, Funabashi, Chiba 274-8507, Japan
Further Information

Publication History

Received 3 August 2011
Publication Date:
07 October 2011 (online)

Abstract

We have recently disclosed that a less hindered class of nitroxyl radicals, i.e., 2-azaadamantan-N-oxyl (AZADO), 1-Me-AZADO, and 9-azabicyclo[3.3.1]nonan-N-oxyl (ABNO), exhibit marked catalytic activity for the oxidation of alcohols with the aid of environmentally friendly oxidants, offering a green and sustainable option for current alcohol oxidation. Encouraged by their outstanding catalytic performance, we envisioned the development of scalable routes to these radicals that could be extended to the commercialization of these radicals for benchtop use as well as for industrial use as optional reagents that complement TEMPO, the flagship compound of stable nitroxyl radicals. We herein describe short and reproducible preparation methods for AZADO and 1-Me-AZADO, featuring an efficient construction of the 2-azaadamantane skeleton.

1 Introduction

2 1-Me-AZADO and AZADO: First-Generation Syntheses

3 Second-Generation Synthesis of 1-Me-AZADO

4 Synthetic Venture towards 2-Azaadamantane: Second-Generation Synthesis of AZADO

5 Conclusion