Triethylamine alcohol oxidation

Problem 18.60 Synthesize the following compounds from alcohols of four or fewer C s, cyclohexanol and any needed solvents and inorganic reagents, (a) n-hexylamine, (h) triethylamine N-oxide, (c) 4-(N-methylamino)heptane, (d) cyclohexyldimethylamine, (e) cyclopentylamine, (/) 6-aminohexanoic acid. 

One of the best activators fw dimethyl sulfoxide is the complex of sulfur trioxide/pyiidine, which in the presence of triethylamine rapidly oxidizes primary and secondary alcrdmls to aldehydes and ketones in very good yields at ambient temperature. This reagent also allows the very useM crmversion of allylic alcohols to the corresponding a, unsaturated carbonyl compounds. A further advantage of this procedure over many of the others is the ease of woiit-up, especially over the dimethyl sulfoxide-dicy-clohexylcarbodiimide method. 

Photochemical Cleavage (see p. 335). The energy of light of 600-300 nm is 48-96 kcalmoP (200-400 kJ moP ), which is of the order of magnitude of covalent-bond energies. Typical examples are photochemical cleavage of alkyl halides in the presence of triethylamine, alcohols in the presence of mercuric oxide and iodine,alkyl 4-nitrobenzenesulfenates, chlorine, and of ketones ... 

The oxidation of alcohols under essentially neutral conditions has been achieved in dimethyl sulfoxide containing one or several additives (Table 4). Most reactions were performed by adding oxalyl chloride and triethylamine (Swern oxidation) under these conditions both aldehydes 9- 154, 241, 327, 624, 688, 806, 862 - 865, 867 - 876 ketOneS ... 

Hydrazones derived from unsubstituted hydrazine are mostly rather unstable and have only specialized preparative interest, e.g., in Wolff-Kishner reduction897 and synthesis of heterocycles. In many cases it is difficult to prepare them because hydrazine tends to react with both amino groups, thereby yielding azines an excess of hydrazine is usually used so as to avoid this azine formation. The condensing agent may be triethylamine, barium oxide, or sodium hydroxide, sometimes in alcohol. Diethyl phosphonate898 has been recommended as an excellent solvent that is said also to catalyse formation of the hydrazone. 

N-Chlorosuccinimide dimethyl sulfide triethylamine Corey oxidation Ketones from sec. alcohols... 

One of the most used alcohol oxidations in organic synthesis is the Swern oxidation. A large number of variants exist for this reaction, but a common one involves DMSO, oxalyl chloride, and a base (pyridine, dimethylaminopy-ridine, and triethylamine are common). The currently accepted mechanism is shown below along with electron pushing for some steps. The first part of the mechanism involves activation of DMSO by reaction with oxalyl chloride. This is followed by nucleophilic attack of the alcohol on this activated species, creating an alkoxysulfonium intermediate. 

To a mixture of 100 ml of dry dichloromethane, 0.10 mol of propargyl alcohol and 0.11 mol of triethylamine was added a solution of 0.05 mol of Ph2PCl in 75 ml of dichloromethane in 3 min between -80 and -90°C. The cooling bath was removed, and when the temperature had reached 10°C, the reaction mixture was poured into a solution of 2.5 ml of 362 HCl in 100 ml of water. After vigorous shaking the lower layer was separated and the aqueous layer was extracted twice with 25-ml portions of dichloromethane. The combined solutions were washed twice with water, dried over magnesium sulfate and then concentrated in a water-pump vacuum, giving almost pure allenyl phosphine oxide as a white solid, m.p. 98-100 5, in almost 1002 yield. 

The oxidation of alcohols by treatment of their corresponding chloroform-ates with DMSO and triethylamine has been reported by Barton. Preliminary results indicate this to be a useful method for preparation of aldehydes but cyclic secondary alcohols are converted to ketones in relatively low yields. 

A mixture of monolauryl phosphate sodium salt and triethylamine in H20 was treated with glycidol at 80°C for 8 h to give 98% lauryl 2,3-dihydro-xypropyl phosphate sodium salt [304]. Dyeing aids for polyester fibers exist of triethanolamine salts of ethoxylated phenol-styrene adduct phosphate esters [294], Fatty ethanolamide phosphate surfactant are obtained from the reaction of fatty alcohols and fatty ethanolamides with phosphorus pentoxide and neutralization of the product [295]. A double bond in the alkyl group of phosphoric acid esters alter the properties of the molecule. Diethylethanolamine salt of oleyl phosphate is effectively used as a dispersant for antimony oxide in a mixture of xylene-type solvent and water. The composition is useful as an additive for preventing functional deterioration of fluid catalytic cracking catalysts for heavy petroleum fractions. When it was allowed to stand at room temperature for 1 month it shows almost no precipitation [241]. 

Esters of the homologous acids are prepared by adding silver oxide in portions rather than in one lot to a hot solution or suspension of the diazo ketone in an anhydrous alcohol (methyl, ethyl or n-propyl alcohol) methanol is generally used and the silver oxide is reduced to metallic silver, which usually deposits as a mirror on the sides of the flask. The production of the ester may frequently be carried out in a homogeneous medium by treating a solution of the diazo ketcne in the alcohol with a solution of silver b izoate in triethylamine. 

Dehydration of (3-nitro alcohols using DCC gives a mixture of E/Z nitroalkenes 48 The pure (E)-isomers are obtained on treatment with catalytic amounts of triethylamine or polymer-bound triphenylphosphine (TPP) (Eq. 3.28).51 When (Z) nitroalkenes are desired, the addition of PhSeNa to the E/Z mixture and protonation at -78 °C followed by oxidation with H202 gives (Z)-nitroalkenes (Eq. 3.29).52... 

Chloro-l,3,2 oxazaphospholidine-2-oxide 158a was formed stereoselectively in the reaction of (l/ ,2/ )-(-)-a-(l-isopropylaminoethyl)benzyl alcohol 157 and phosphoryl chloride in the presence of triethylamine (Scheme 44) [65, 75],... 

Treatment of the elimination product 107 with triethylamine resulted in smooth isomerization of the olefin, to afford the a,p-unsaturated ketone 108. Ally lie oxidation of 108 then generated the secondary alcohol 109 in 72 % yield. The acetonide and silyl ether functions of 109 were cleaved in one reaction to afford a tetraol intermediate that was regioselectively acylated at the secondary alcohol functions, to provide the triacetate 110 in high yield (89 %). Hydrogenolysis of the benzyl ether... 

Oxidation. DMSO activated by P205 (1 equiv.) and in combination with triethylamine is useful for oxidation of alcohols to ketones and aldehydes, particularly in cases where the Swern reagent results in chlorinated byproducts. Yields are typically 80-85%. 

The use of chlorodiphenylphosphine to induce a [2,3]-sigmatropic rearrangement of enediynyl propargylic alcohols is one of the first synthetic methods adopted for the preparation of enyne-allenes. For instance, treatment of 108 with chlorodiphenylphosphine and triethylamine at -78 to 0°C afforded the enyne-allenylphosphine oxide 109 in 63% isolated yield (Scheme 20.23) [9]. Thermolysis of 109 at 37 °C in the presence of 1,4-CHD generated the biradical 110, leading to 111 and combina-... 

Although the present procedure illustrates the formation of the diazoacetic ester without isolation of the intermediate ester of glyoxylic acid />-toluenesulfonylhydrazone, the two geometric isomers of this hydrazone can be isolated if only one molar equivalent of triethylamine is used in the reaction of the acid chloride with the alcohol. The extremely mild conditions required for the further conversion of these hydrazones to the diazo esters should be noted. Other methods for decomposing arylsulfonyl-hydrazones to form diazocarbonyl compounds have included aqueous sodium hydroxide, sodium hydride in dimethoxyethane at 60°, and aluminum oxide in methylene chloride or ethyl acetate." Although the latter method competes in mildness and convenience with the procedure described here, it was found not to be applicable to the preparation of aliphatic diazoesters such as ethyl 2-diazopropionate. Hence the conditions used in the present procedure may offer a useful complement to the last-mentioned method when the appropriate arylsulfonylhydrazone is available. 

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