<i>N-</i>Tosyloxycarbamates as a Source of Metal Nitrenes: Rhodium-Catalyzed C−H Insertion and Aziridination Reactions
作者:Hélène Lebel、Kim Huard、Sylvain Lectard
DOI:10.1021/ja0552850
日期:2005.10.1
N-tosyloxycarbamates to generate metal nitrenes which undergo intramolecular C-H insertion or aziridination reaction is described. Aliphatic N-tosyloxycarbamates produce oxazolidinones with high yields and stereospecificity through insertion in benzylic, tertiary, and secondary C-H bonds. Intramolecular aziridination occurs with allylic N-tosyloxycarbamates to produce aziridines as single diastereomers
<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.
aziridination (trisubstituted alkenes), which can then be ring opened with benzoic acid. The resulting chiral cyclic carbamates can be hydrolyzed under basic conditions to provide versatile chiral 2-amino-1,3-diols with vicinal stereocenters.
Aerobic C−N Bond Formation through Enzymatic Nitroso‐Ene‐Type Reactions**
作者:Christina Jäger、Mona Haase、Katja Koschorreck、Vlada B. Urlacher、Jan Deska
DOI:10.1002/anie.202213671
日期:2023.2.6
laccases participate in C−N bond-forming reactions through the generation of reactive nitroso intermediates from acylated hydroxylamines. The formal allylic C−H bond activation proceeds with air as the terminal oxidant and provides high yields both in intramolecular and intermolecular aminationreactions through this unprecedented biocatalytic nitroso-ene-type reaction pathway.
Copper-Catalyzed Aerobic Oxidation of Hydroxamic Acids Leads to a Mild and Versatile Acylnitroso Ene Reaction
作者:Charles P. Frazier、Jarred R. Engelking、Javier Read de Alaniz
DOI:10.1021/ja204603u
日期:2011.7.13
A mild formation of transient acylnitroso intermediates using a copper chloride catalyst and 1 atm of air as the terminal oxidant is described. The mild reaction conditions enable the inter- and intramolecular acylnitroso ene reaction with a wide range of functionalized alkene partners, as well as the first asymmetric variant. Notably, this transformation provides a practical and operationally simple method for effecting allylic amidation using an environmentally benign oxidant and a readily abundant transition metal.