Titanocene(III) Chloride-Mediated Reductions of Oxazines, Hydroxamic Acids, and N-Hydroxy Carbamates
摘要:
Titanocene(III) chloride (Cp2TiCl), generated in situ, reduces N-O bonds of various substrates in good to excellent yields (72-95%). Reactions may be performed with stoichiometric Cp2TiCl or with catalytic Cp2TiCl.
Nitrile oxides are oxidized by tertiary amine N-oxides in different solvents at room temperature to afford in the presence of dienes nitrosocarbonyl adducts in fair yields. The mild conditions used in oxidizing a variety of nitrile oxides promise a wide application of this method in synthetic processes.
Regio- and Stereochemically Controlled Formation of Hydroxamic Acid Containing <i>a</i><i>nti</i>- or <i>s</i><i>yn</i>-1,4-Cycloalkenols from Acylnitroso-Derived Diels−Alder Adducts
作者:Matthew D. Surman、Marvin J. Miller
DOI:10.1021/jo010094a
日期:2001.4.1
Treatment of acylnitroso hetero Diels-Alder cycloadducts 2 with iron(III) or copper(II) in an alcohol solvent induces ring opening to afford predominantly monocyclic anti-1,4-hydroxamic acids 3. However, treatment of cycloadducts 2 with copper(II) in toluene reverses the stereoselectivity of the ring opening to afford syn-1,4-hydroxamic acids 4. These regio- and stereoselective processes separately
Copper-Catalyzed Aerobic Oxidation of <i>N</i>-Substituted Hydroxylamines: Efficient and Practical Access to Nitroso Compounds
作者:Charles P. Frazier、Alejandro Bugarin、Jarred R. Engelking、Javier Read de Alaniz
DOI:10.1021/ol301414k
日期:2012.7.20
A general and efficient aerobic oxidation of N-substituted hydroxylamines is described. The mild reaction conditions employed provide a catalytic and sustainable alternative to stoichiometric oxidation methods to gain access to a range of nitroso compounds, such as acylnitroso, nitrosoformate, nitrosoformamide, iminonitroso, arylnitroso, and P-nitrosophosphine oxide derivatives in excellent yield.
Titanocene(III) Chloride-Mediated Reductions of Oxazines, Hydroxamic Acids, and <i>N</i>-Hydroxy Carbamates
作者:Cara Cesario、Lawrence P. Tardibono、Marvin J. Miller
DOI:10.1021/jo802184y
日期:2009.1.2
Titanocene(III) chloride (Cp2TiCl), generated in situ, reduces N-O bonds of various substrates in good to excellent yields (72-95%). Reactions may be performed with stoichiometric Cp2TiCl or with catalytic Cp2TiCl.