copper(II) salts and Dess–Martin periodinane via radical intermediates, as evidenced by TEMPO spin‐trapping experiments. This new method of radical generation is compatible with functionalization and CC bond formation through Giese‐type addition reactions (see scheme; DMSO=dimethyl sulfoxide, TEMPO=2,2,6,6‐tetramethyl‐1‐piperidinyloxyl, free radical).
TEMPO-Induced Generation of Alkyl Radicals from <i>B</i>-Alkylcatecholboranes
作者:Cyril Ollivier、Rachel Chuard、Philippe Renaud
DOI:10.1055/s-1999-2718
日期:1999.6
B-alkylcatecholboranes react efficiently with 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) to give alkyl radicals. In the presence of an excess of TEMPO, the generated radicals are efficiently converted to alkoxyamine derivatives.
B-烷基儿茶酚硼烷与 2,2,6,6-四甲基哌啶-N-氧基 (TEMPO) 有效反应生成烷基。在过量的 TEMPO 存在下,产生的自由基有效地转化为烷氧基胺衍生物。
Free-Radical Hydroxylation Reactions of Alkylboronates
作者:Christine Cadot、Peter I. Dalko、Janine Cossy、Cyril Ollivier、Rachel Chuard、Philippe Renaud
DOI:10.1021/jo0201833
日期:2002.10.1
to give alkoxyamines. Reduction of the alkoxyamines with zinc in acetic acid affords the desired alcohols. The whole procedure is particularly mild and does not require any basic condition. The two approaches presented in this paper are valuable and represent mild alternatives to the classical alkaline oxidation of organoboranes to alcohols.
In this report, the single-electron-transfer oxidation of alkyltrifluoroborates and silicates has been studied. Different types of oxidation reagents have been examined, focusing on organic oxidants and particularly the use of dyes in photocatalytic oxidations. Both trifluoroborates and silicates could provide C-centered radicals when using a tritylium salt or the Ledwith–Weitz aminium salt. Photocatalysis
在本报告中,研究了烷基三氟硼酸盐和硅酸盐的单电子转移氧化。已经研究了不同类型的氧化试剂,重点是有机氧化剂,特别是染料在光催化氧化中的使用。当使用三苯甲基盐或 Ledwith-Weitz 铵盐时,三氟硼酸盐和硅酸盐都可以提供 C 中心自由基。Fukuzumi 试剂的光催化表明,在这些条件下,三氟硼酸盐比双儿茶酚硅酸盐更容易氧化。