Alcohols miscellaneous oxidations

Miscellaneous Oxidation Reactions. The kinetic resolution of secondary alcohols is achieved by a palladium-catalyzed enan-tioselective oxidation using Pd[(—)-sparteine]Br2/(—(-sparteine or Pd(CH3CN)2(Br)2/chiral diamine sparteine mimic under an oxygen atmosphere. The chiral amine-dibromide complexes are observed to oxidize secondary alcohols more rapidly than the dichloride complexes (eq 7). This has been attributed to a greater counterion distortion from ideal square planar geometry, which could lower the energy barrier to 8-hydride elimination. 

Miscellaneous Reactions. Ahyl alcohol can be isomerized to propionaldehyde [123-38-6] in the presence of sohd acid catalyst at 200—300°C. When copper or alumina is used as the catalyst, only propionaldehyde is obtained, because of intramolecular hydrogen transfer. On the other hand, acrolein and hydrogen are produced by a zinc oxide catalyst. In this case, it is considered that propionaldehyde is obtained mainly by intermolecular hydrogen transfer between ahyl alcohol and acrolein (31). 

Abstract This is one of the most important classes of oxidation effected by Ru complexes, particnlarly by RnO, [RuO ] , [RnO ] and RuCljCPPhj), though in fact most Ru oxidants effect these transformations. The chapter covers oxidation of primary alcohols to aldehydes (section 2.1), and to carboxylic acids (2.2), and of secondary alcohols to ketones (2.3). Oxidation of primary and secondary alcohol functionalities in carbohydrates (sugars) is dealt with in section 2.4, then oxidation of diols and polyols to lactones and acids (2.5). Finally there is a short section on miscellaneous alcohol oxidations in section 2.6. 

The Oxidation of Amines and Alcohols The Disproportionation of Hydroxylamine Miscellaneous Reactions... 

Most of the compounds that had been reported (before March, 1942) to show cleavage oxidation by periodic acid are recorded in the table the substances are listed alphabetically in the following groups of related compounds (1) carbocyclic compounds (2) carbohydrates (3) a-diketones and a-ketols (4) hydroxyamino compounds (5) polyhydroxy and hydroxyketo acids (6) polyhydroxy alcohols (7) steroids (8) miscellaneous compounds. French journals after May, 1940, and the majority of other foreign publications after June, 1941, were unavailable for the survey. 

Miscellaneous. The amine oxides used in household products are generally alkyl dimethyl amine oxides and are prepared from alcohols as shown below ... 

Oxidation Adjacent to Oxygen of Alcohols by Chromium Reagents 2.7.6 MISCELLANEOUS CHROMATES AND DICHROMATES... 

Nucleophilic Substitution Solvolytic and Elimination Reactions Ring-opening of Epoxides Esters, Ethers, and Related Derivatives of Alcohols Oxidation Reduction Miscellaneous... 

Miscellaneous Reactions. So-called Oxidation-Wittig conditions , where a primary alcohol is oxidised using manganese dioxide in the presence of a stabilised ylide, have been applied for the first time to unactivated alcohols, producing a, 3-unsaturated esters in high yields (Scheme 18). Fluorenyl-... 

Miscellaneous syntheses. Moody et al. (90TL4375 92T3589) have described a synthesis of ascididemin 28 that involves the epoxidation of 1,10-phenanthroline 181, ring opening of the epoxide 182 with 2-iodoaniline to afford the amino alcohol 183, and oxidation followed by photocyclization of the o-iminoquinone 184 (Scheme 29). 

Structure CXXXVTI is compatible with several miscellaneous reactions and properties of tazettine. It accounts for the production of phenanthridine derivatives by zinc dust distillation (128a) and Oppen-auer oxidation (55) more satisfactorily than CXXXII. The double bond of tazettine is sufficiently removed from the nitrogen atom to have no effect on the basicity of the alkaloid. The allylic methyl ether may be cleaved with hydrochloric acid to a mixture of two epimeric allylic alcohols, tazettinol (CLI) and isotazettinol (CLII). Methylation of tazettinol afforded 0-methyltazettine methiodide, identical with that obtained by the methylation of tazettine. Under similar conditions, isotazettinol afforded the epimeric 0-methylisotazettine methiodide. Both methiodides gave 2-(4-methoxyphenyl)-4,5-methylenedioxyben-... 

Miscellaneous ring closure reactions involving carbon-carbon bond formation are shown in Scheme 72 and 73. An oxidation-cyclization-oxidation process was effected by PCC to convert alcohols 197 to 4-piperidones 198 <04JOC3226>. Intramolecular alkylation was used to covert chiral enaminone 199 to 200, a key intermediate in the total synthesis of lepadin alkaloids... 

Miscellaneous. 2,4,5-Trichlorothiazole reacts with propargyl alcohol to form the 2-HC=CCH20-substituted M,5-dichlorothiazo le 4-Methylthiazole is transformed to 4-cyanothiazole by air/NH at 442°C over a Mn oxide-Cr oxide-Mo oxide catalytic mixture 2. 2-Mercapto-4,5-disubstituted thiazoles. are oxidised with NH4/heavy metal catalysts (or compounds thereof) to the corre-... 

Miscellaneous Processes. Hydrogen also may be obtained from calcium hydride, from sodium hydride, as a by-product from fermentation processes (butyl alcohol-process), from coke-oven gas, and by the partial oxidation of powdered coal by a process similar to that described for hydrocarbons. 

MISCELLANEOUS. Sodium hydride, particularly as the dispersion, is effective for removing the last traces of water, alcohols, oxygen, and some sulfur compounds from solvents and certain gases. It reacts with ammonia to form sodium amide, with carbon oxides to form products including formate and oxalate, and with sulfur dioxide to form sodium hydrosulflte. Smalley (52) has tried it for the desulfurization of iron and steel. Its advantage over sodium metal for these reactions is that it holds its fine particle size and reactive surface up to 400 °C., while sodium melts and coalesces at 100°C. unless continually redispersed. 

Miscellaneous Reactions. A silyl-containing alcohol derived from cyclohexene oxide can be converted to a nine-membered lactone on treatment with CAN, presumably via the oxidative generation and subsequent transformations of an alkoxy radical (eq 29). ... 

Miscellaneous Reactions. In addition to the key reactions above, DDQ has been used for the oxidative removal of chromium, iron, and manganese from their complexes with arenes and for the oxidative formation of imidazoles and thiadia-zoles from acyclic precursors. Catal)ftic amounts of DDQ also offer a mild method for the oxidative regeneration of carbonyl compounds from acetals, which contrasts with their formation from diazo compounds on treatment with DDQ and methanol in nonpolar solvents. DDQ also provides effective catalysis for the tetrahydropyranylation of alcohols. Furthermore, the oxidation of chiral esters or amides of arylacetic acid by DDQ in acetic acid provides a mild procedure for the synthesis of chiral a-acetoxy derivatives, although the diastereoselectivity achieved so far is only 65-67%. ... 

Miscellaneous Ozonations. Ozonation offers a simple neutral alternative for oxidation of secondary alcohols to ketones (eq 30). ... 

To choose proper test substances, McReynolds studied the behavior of a large number of substances of the following compound classes alcohols, glycols, aldehydes, ketones, esters, acetals, ethers, oxides, hydrocarbons, chloro compounds, difunctional and polyfunctional compounds, and other miscellaneous substances. " For the stationary phase classification, he eventually proposed benzene, n-butanol, 2-pentanone, 1-nitropropane, and pyridine to represent compounds of different chemical interactions. " McReynolds characteristic phase constants for these five compounds describe the selectivity of the phase. 

---