Amine oxides, anhydrous

Amides, macrobicyclic, reduction of, 54, 89 Amine oxides, anhydrous, 50,... 

Amine oxides, anhydrous, SO, 55, 58 Amines, protecting group for, 50,12 AMINES FROM MIXED CARBOXYLIC-CARBONIC ANHYDRIDES 1-PHENYLCYCLOPENTYL-AMINE,51,4S... 

Alenylacetylenes, 50,101 Aluminum chloride, with ethylene and p-methoxyphenylacetyl chloride to give 6-methoxy-/3-tetralone, 51,109 with propylene and acetyl chloride to give 4-chloropentan-2-one, 51,116 Amine oxides, anhydrous, 50, 55, 58 Amines, protecting group for, 50,12 AMINES FROM MIXED CARBOXYLIC-CARBONIC ANHYDRIDES 1-PHENYLCYCLOPENTYLAMINE,... 

A solution of 21.3 g. (0.10 mole) of freshly distilled N,N-dimethyldodecylamine (Note 1), 9.6 g (0.10 mole) of 94% <-butyl hydroperoxide (Note 2), and 0.050 g. of vanadium oxyacetylacetonate (Note 3) in 27 g. (34 ml.) of Cbutyl alcohol is placed in a 250-ml. round-bottomed flask fitted with a. thermometer, a reflux condenser, and a heating mantle. The reaction mixture is heated to approximately 65-70°, at which point an exothermic reaction begins. The heating is discontinued until the vigorous exothermic reaction subsides (about 5 minutes) and then the reaction mixture is heated at reflux (the reaction mixture boils at 90°) for 25 minutes. After the resulting mixture has been cooled to room temperature, it is analyzed (Note 4) to establish the absence oft-butyl hydroperoxide, and then concentrated with a rotary evaporator (30-35° bath with 30-40 mm. pressure). The crude solid residue is triturated with 50 ml. of cold (0-5°), anhydrous diethyl ether and then filtered under conditions which prevent exposure of the residual amine oxide to atmospheric moisture (Note 5). The residual solid is washed with 50 ml. of cold (0-5°) anhydrous diethyl ether and then dried under reduced pressure to leave 12.9-15.5 g. of the crystalline amine oxide, m.p. 131-131.5°. Concentration of the mother liquors and trituration of the residual paste with 25 ml. of cold (0-5°) anhydrous diethyl ether separates another 4.9-3.4 g. of the amine oxide, m.]). 130-131°. The total yield of the crystalline amine oxide (Note 6) is 17.4-18.9 g. (76 83%). 

Aqueous or alcohol solutions of amine oxides are normally obtained by oxidizing tertiary amines with either hydrogen peroxide or a peracid.4 For example, N,N-dimethyldodecyl-amine oxide has been prepared by treating N,N-dimethyl-dodecylamine with aqueous hydrogen peroxide.5 The procedure illustrated in this preparation permits the oxidation of tertiary amines with /-butyl hydroperoxide in organic solvents under relatively anhydrous conditions.6 In this procedure the reaction time is short and the method is as convenient as the use of aqueous hydrogen peroxide or a peracid as the oxidant. Furthermore, isolation of the anhydrous amine oxide is often relatively simple. 

For dehydration 10 g. of the amine oxide dihydrate is placed in a 150-ml. flask which has a long, wide neck. Some boiling chips are added, and the compound is heated in an oil bath under a water pump vacuum of 10-12 mm. A calcium chloride tube is placed between the water pump and the flask. At an oil bath temperature of 120°, the amine oxide dihydrate melts and begins to bubble. The temperature is raised very slowly. After most of the water is off, the temperature of the bath is maintained at 140-150° for 10 minutes. A new calcium chloride tube is placed in the apparatus, and it is again heated under vacuum. At 180° sublimation starts, and anhydrous amine oxide collects in the neck of the flask. The mixture is held at a bath temperature of 190-200° for 1.5 hours to complete the sublimation. The yield of anhydrous trimethylamine oxide is around 95%. The material is extremely hygroscopic. A sample in a capillary tube melts at 208° after subliming around 180°. 

Amine oxides. A convenient procedure for the oxidation of a tertiary amine which affords the amine oxide easily in completely anhydrous form is illustrated as follows.1 A mixture of 23.5 g. of N,N-dimethyldodecylamine (Eastman, 90%),... 

CARBON OXYCHLORIDE (75-44-5) COCI2 Highly toxic and corrosive gas. Deconqioses slowly with water, producing hydrochloric acid and carbon oxides. Deconqjoses above 572°F/300°C, forming toxic and corrosive gases of hydrogen chloride and carbon monoxide chlorine. Reacts violently with strong oxidizers, amines, alkalis, anhydrous ammonia, isopropanol, chemically active metals aluminum, silicon tetrahydride, sodium. Forms shock-sensitive material with potassium. Incompatible with tert-alcohols. 

Anhydrous sodium metasilicate and anhydrous tetrasodium EDTA are readily available anhydrous amphoterics and amine oxides are not. 

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. 

The properties of 1,1-dichloroethane are Hsted ia Table 1. 1,1-Dichloroethane decomposes at 356—453°C by a homogeneous first-order dehydrochlofination, giving vinyl chloride and hydrogen chloride (1,2). Dehydrochlofination can also occur on activated alumina (3,4), magnesium sulfate, or potassium carbonate (5). Dehydrochlofination ia the presence of anhydrous aluminum chloride (6) proceeds readily. The 48-h accelerated oxidation test with 1,1-dichloroethane at reflux temperatures gives a 0.025% yield of hydrogen chloride as compared to 0.4% HCl for trichloroethylene and 0.6% HCl for tetrachloroethylene. Reaction with an amine gives low yields of chloride ion and the dimer 2,3-dichlorobutane, CH CHCICHCICH. 2-Methyl-l,3-dioxaindan [14046-39-0] can be prepared by a reaction of catechol [120-80-9] with 1,1-dichloroethane (7). 

With many organic compounds, aluminium shows high corrosion resistance either in the presence or absence of water. The lower alcohols and phenols are corrosive when they are completely anhydrous —rarely encountered in practice —since repair of breaks in the natural protective oxide film on aluminium cannot take place in the absence of water. Amines generally cause little attack unless very alkaline. 

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