Tethered Aminohydroxylation: Dramatic Improvements to the Process
作者:Timothy J. Donohoe、Carole J. R. Bataille、William Gattrell、Johannes Kloesges、Emilie Rossignol
DOI:10.1021/ol070430v
日期:2007.4.1
[reaction: see text] Changing the identity of the N leaving group on a hydroxylamine-based reoxidant gives a dramatic improvement to the tetheredaminohydroxylationreaction. Using OCOC6F5 as a leaving group means that only 1 mol % of osmium is required and yields as high as 98% can be obtained. Acyclic homoallylic alcohols were substrates considered too unreactive for effective use in the tethered
<i>N</i>-Sulfonyloxy Carbamates as Reoxidants for the Tethered Aminohydroxylation Reaction
作者:Timothy J. Donohoe、Majid J. Chughtai、David J. Klauber、David Griffin、Andrew D. Campbell
DOI:10.1021/ja057389g
日期:2006.3.1
for the tetheredaminohydroxylation (TA) reaction is reported. These new conditions obviate the requirement for lithium hydroxide and tBuOCl in the oxidation mixture. In addition to providing aminohydroxylation products in good yields, the catalyst loadings can be reduced to just 1 mol % osmium. Moreover, for the first time, homoallylic alcohols are now viable substrates for the TA reaction.
(dr up to >20:1). This new transformation applies a functionalized hydroxylamine and Et3N·3HF as the nitrogen and fluorine source, which facilitates the efficient synthesis of β-fluoro primaryamines and amino acidsfromallylicalcohol derivatives. Preliminary mechanistic studies reveal that an iron–nitrenoid is a possible intermediate and that its reactivity and enantioselectivity can be efficiently
Iron-Catalyzed Intra-intermolecular Aminoazidation of Alkenes
作者:Sandra Abi Fayssal、Alessandro Giungi、Farouk Berhal、Guillaume Prestat
DOI:10.1021/acs.oprd.9b00400
日期:2020.5.15
An intra-intermolecular iron-catalyzed aminoazidation of non-activated alkenes is reported for the preparation of imidazolidinone, oxazolidinone, and pyrrolidinone derivatives. The method uses cheap and abundant iron as a catalyst and commercially available TMSN3 as an azide source. This domino process allows, in a single operating step, for a ring-closure that generates an aza-heterocycle and the introduction of an azido appendage tethered to the heterocycle. The conditions developed offer a sustainable alternative method for the preparation of unsymmetrical vicinal diamine compounds.