Formation of diphenyl nitroxide in diphenylamine inhibited autoxidations

Author:

Adamic K.,Dunn M.,Ingold K. U.

Abstract

The formation of diphenyl nitroxide in diphenylamine inhibited, α,α′-azo-bis-isobutyronitrile initiated, autoxidations at 65° has been studied by electron spin resonance. Diphenylamine is oxidized to a diphenylamino radical which is then converted to the nitroxide by an oxygen atom transfer from a peroxy radical. The initial rates of conversion of diphenylamine to diphenyl nitroxide and the maximum nitroxide concentrations attained are generally greater for oxidations with tertiary peroxy radicals than for oxidations with primary or secondary peroxy radicals. The lower efficiency of nitroxide formation by primary and secondary peroxy radicals is attributed to a cage disproportionation between alkoxy radical and nitroxide which leads to the formation of a carbonyl compound and diphenyl hydroxylamine. This reaction cannot occur with tertiary radicals. The rate of formation of diphenyl nitroxide is greater for tertiary peroxy radicals which give stable tertiary alkoxy radicals. Nitroxide formation is inhibited by secondary, but not by tertiary, hydroperoxides.

Publisher

Canadian Science Publishing

Subject

Organic Chemistry,General Chemistry,Catalysis

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3