Amines ozonides

Commercially, pure ozonides generally are not isolated or handled because of the explosive nature of lower molecular weight species. Ozonides can be hydrolyzed or reduced (eg, by Zn/CH COOH) to aldehydes and/or ketones. Hydrolysis of the cycHc bisperoxide (8) gives similar products. Catalytic (Pt/excess H2) or hydride (eg, LiAlH reduction of (7) provides alcohols. Oxidation (O2, H2O2, peracids) leads to ketones and/or carboxyUc acids. Ozonides also can be catalyticaHy converted to amines by NH and H2. Reaction with an alcohol and anhydrous HCl gives carboxyUc esters. 

A method for the conversion of alkenes into tertiary amines is exemplified by the formation of A-(3-phenylpropyl)piperidine when the ozonide of 4-phenylbut-l-ene is heated with piperidine in the presence of 4 A molecular sieves (equation 11). The carbon atom which is eliminated appears as piperidinium formate41. 

Preservatives, pharmaceutical preparations, 623 PRESS technique, NIR spectrophotometry, 624 Primary amines, dioxirane oxidation, 1151 Primary ozonides (POZ), 716, 717 dialkyl peroxide formation, 706 IR spectroscopy, 718, 719-20 microwave spectroscopy, 721 molecular model, 750 NMR spectroscopy, 709, 723-4 octaUn ozonation, 165 ozone water disinfection, 606 7r-complexes with ozone, 732... 

Wenn man Alkene ozonisiert, die gebildeten Ozonide ohne Isolierung partiell hydriert und dann reduktiv mit Ammoniak, primaren Oder sekundaren Aminen und Wasserstoff aminiert, erhalt man je nach Aiken einheitliche Amine (primare, sekundare bzw. ter-tiare) Oder Amin-Gemische2. 

Ozonolysis of alkenes in the presence of amine A-oxides resulted in reductive ozonolysis, i.e, the direct formation of aldehydes in high yields, avoiding the generation and isolation of ozonides or other peroxide products. Use of DMSO and tertiary amines improved the yield of aldehydes but some amount of ozonides remained. This... 

On stirring at room temperature ozonides of terminal alkenes (prepared in dichloromethane at — 70 °C) with a polymer-supported tertiary amine obtained from chloromethylated poly(styrene/divinylbenzene) and piperidine, followed by filtration and concentration under reduced pressure, the products (aldehydes or ketones) can be obtained easily in almost pure form in high yields <2003T493>. However, yields are low for cycloalkenes because apparently they form monomeric and polymeric ozonides. 

An older paper <1971MI873> reported that ozonolysis of alkenes in the presence of tertiary amines resulted in the formation of aldehydes. A recent reinvestigation <20060L3199> has shown that amine oxides were responsible for this reductive ozonolysis . Indeed, pretreatment of the tertiary amines with ozone, giving rise to amine oxides, accounted for this phenomenon. A preparative method emerged, by treating the alkene (e.g., 1-decene) at 0 °C with a solution of 2% 03/02 in dichloromethane (2 equiv of ozone relative to the alkene) in the presence of an excess (about threefold molar excess) of A-methylmorpholine A-oxide, pyridine A-oxide, or l,4-diazabicyclo[2.2.2]octane A-oxide (DABCO A-oxide). Yields of aldehydes (nonanal in the above example) were 80-96%, and the excess of amine oxide ensured the absence of residual ozonide (Scheme 21). 

Low-density lipids in the blood cause cholesterol deposits. Their presence and nature, including the position and number of double bonds, can be analyzed by means of ESI-MS techniques <2000JMP224>. Reverse-phase HPLC microsamples containing phospholipids were treated with bis(trimethylsilyl) trifluoroacetamide, then with methoxy-amine, and then exposed for 8 min to ozone gas at room temperature ESI-MS followed and showed the fragments corresponding to ozonides. 

Various oligomeric condensates are formed from phenolic and aromatic amine AO and AOZ as a consequence of interactions of these reactive stabilizers with oxidizing species formed in stabilized polymers, e.g. with alkylperoxyls, alkyl hydroperoxides or ozonides [15-17]. Stabilizing efficiency is preserved in some of these compounds the latter have been discussed however mostly in connection with mechanism of action of AO or AOZ [6]. 

Ozonide (in situ hergestellt aus Alkenen) lassen sich als verkappte Aldehyde reduktiv aminieren, wobei Ammoniak18-20, primare18,20 oder sekundare20 Amine eingesetzt werden konnen (vgl. Tab. 82, S. 426). Aus asymmetrischen Olefinen werden Amin-Gemische erhalten z.B.20 ... 

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