Alkoxides reactions

In spite of the extensive kinetic work of Chapman and co-workers, much remains to be done on the reactivity of azines with nucleophiles. The data available on substitution by alkoxide ions are especially meager. The missing information on alkoxide reactions should give a better picture of the activation of different ring-positions than is possible with the data on aminations. The latter include the effects shown in 235, 276, and 277 in addition to activation by the azine-nitrogens. 

Rhodium catalysts have also been used. Benzylic halides were converted to carboxylic esters with CO in the presence of a rhodium complex. In this case, the R could come from an ether R20, a borate ester B(OR )3, or an Al, Ti, or Zr alkoxide. Reaction with an a,co-diiodide, BU4NF and Mo(CO)e gave the corresponding lactone. ... 

Alkoxylation of MHal is performed by KOR, NaOR, or LiOR or by ammonia in solution in alcohol (formally ammonium alkoxide). Reaction with NaOR is accompanied by formation of NaCl, which is almost completely insoluble in organic solvents and is, therefore, used in the synthesis of soluble metal alkoxides. One of the first examples of application of such reactions has not lost its importance as a method of synthesis to this day ... 

Like their aluminum counterparts, gallium alkoxides are susceptible to hydrolysis, giving Ul-defined products. Methanolysis of hydrated Ga + ions produces Ga(OMe) + and Ga(OMe)2+ in solvated forms, as well as polymeric complexes. Ga(OPh)3 reacts with boiling MeOH or EtOH to form the corresponding alkoxide. Reaction of the trialkoxide compounds with other metal alkoxides, for example, LiOR, results in the formation of four-coordinate complex anions of the type [Ga(OR)4] A recent review of sesquihahdes/oxides... 

In reactions of [Mn(NOXCO)2Cp- / ][PFg] and derivatives with alkoxides the products possess a chiral metal center. The reaction sequence illustrates the application of a cationic metal carbonyl-alkoxide reaction to resolve optical isomers of [Mn(NOXCOXPPh3XCp-i/ )][PFg] using menthoxide Na[OC,oH,g]... 

Trityl ethers may be prepared from tritanol by reaction with an alcohol in the presence of an acid catalyst or from trityl chloride by reaction with an alcohol or an alkoxide. Reaction 1 is reversible and is... 

The organotin methoxides cannot readily be prepared from methanol by reaction 14-2 because its boiling point is too low, and it does not form an azeotrope with water. The methoxides and alkoxides derived from other volatile alcohols can, however, readily be prepared by heating together the bis(trialkyltin) oxide and dialkyl carbonate the exchange reaction between the tin oxide and carbonate gives the tin alkoxide and the alkyltin carbonate (reaction 14-13), which readily decarboxylates to give more alkoxide (reaction 14-14)4... 

Alkoxide reactions with the hydroxyls of an oxide surface can be performed by contacting the surface with a solution of the alkoxide in the parent alcohol or in another solvent, more or less polar. The role of the solvent can be very important for the anchorage efficiency. The alkoxide concentration to be used can be choisen by knowing the surface hydroxyl density, the prevailing stoichiometry and the alkoxide-surface reactivity. 

R = Bz) was prepared directly from (143) by treatment with sodium methoxide at room temperature. The JV-acetyl compound (189, R = Ac) also gave (190) with hot, ethanolic sodiiun ethoxide. A distinction between (143) (and its iV-acetyl analog) and (189, R = Bz) (and its A -acetyl analog) was noted in the formation of a mixture of aziridines (188, R = H, Bz, or Ac) and oxazolines C(144) and the 3-methyl analog] from alkoxide reactions on (143), but of the aziridine (190) only, in the reactions of (189) with alkoxides this difference was explained on conformational grounds. Potassium cyanide in A, A -dimethylform-amide converts (143) mainly into (188, R = Bz) the oxazoline (144) is a major by-product. ... 

Therefore, TPAOH plays several roles it is the catalyst of alkoxide reactions (e.g. hydrolysis, alcoholysis and polymerisation/depolymerisation) and the gelling agent. 

F.H. Oppenauer Oxidation. In oxidation reactions involving both Cr(VI) and DMSO reagents, the alcohol is converted to a complex in which the a-hydrogen of an alcohol can be removed as an acid. A classical and alternative method for the oxidation of alcohols focuses on the reversible reaction between ketones and metal alkoxides, which is especially effective when the metal is aluminuml34 xhe reversibility of the aluminum alkoxide reaction was first demonstrated by Verley 35 Ponndorf 36 for the reaction of a ketone with an aluminum alkoxide, which led to formation of a new aluminum alkoxide and a new ketone. In... 

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