Triethylamine, oxidation

Similar hydroxylation-oxidations can be carried out using a catalytic amount of osmium tetroxide with A-methylmorpholine oxide-hydrogen peroxide or phenyliodosoacetate." A recent patent describes the use of triethylamine oxide peroxide and osmium tetroxide for the same sequence. Since these reactions are of great importance for the preparation of the di-hydroxyacetone side-chain of corticoids, they will be discussed in a later section. 

Man erhalt auf diese Weise z.B. aus Triethylamin-oxid und 1-Brom-octan bzw. Brom-essigsaure-ethylester als Elektrophil 1-Diethylamino-octan (51%) bzw. Diethylamino-essigsaure-ethylester (31%) und aus l-Methyl-piperidin-1-oxid und 1-Brom-octan bzw. Bromessigsaure-ethylester 1-Octyl-piperidin (47%) bzw. Piperidinoessigsaure-ethylester (38%). Nach dem zweiten Reaktionsweg erhalt man z. B. aus Cyclohexyl-dimethyl-amin-oxid mit Cyan-trimethyl-silan als Nukleophil (Cyclohexyl-methyl-amino)-acetonitril (71%). 

Oxidation of alcohols. These reagents react at low temperatures (-78°) in ch2ci2 to form a zwitterionic complex (I), which loses C02 at O 1 to form 2. The complex 1 in the presence of triethylamine oxidizes primary and secondary alcohols to the corresponding carbonyl compounds in 70-90% yield. 

Amine oxides are interesting for two reasons. First, amine oxides decompose when strongly heated, and this reaction provides a useful preparation of alkenes. With triethylazane oxide (triethylamine oxide), ethene is formed ... 

Dialkyl sulfoxides such as DMSO work as oxidants for the selective preparation of disulfides. The order of thiol reactivity is ArSH > ArCH2SH > RSH. Several amine oxides, such as pyridine N-o -ides and triethylamine oxide, also oxidize sulfides to sulfoxides, but the reaction generally requires higher temperatures. 

A soln. of triethylamine in deuteriochloroform treated in one portion with 2-phenyl-sulfonyl-3-phenyloxaziridine (Davis reagent), and stirred for 1 h - triethylamine oxide. Y > 95% by C - NMR. The amines must be more basic than pyridine, which was not oxidized olefinic double bonds and sec. alcohols were unaffected. F.e., also hydroxylamines or nitrones from sec. amines, s. W.W. Zajac, Jr. et al., J. Org. Chem. 

Substituted boron analogues of p-proline were synthesized efficiently via 1,3-dipolar cydoadditions of azomethyne ylides, generated from N-alkyl amino acids and formaldehyde, to alkenyl boronates. Heterocydic cycloadducts were also good precursors of the corresponding pyrrolidin-3-ols by oxidation with triethylamine oxide (Scheme 9.46) [99]. 

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