2.5- Di-f-butylpyridine

AgOTf, Mel, 2,6-di-f-butylpyridine, 39-96% yield. This method can be used to prepare alkyl, benzyl, and allyl ethers. ... 

Without additives, radical formation is the main reaction in the manganese-catalyzed oxidation of alkenes and epoxide yields are poor. The heterolytic peroxide-bond-cleavage and therefore epoxide formation can be favored by using nitrogen heterocycles as cocatalysts (imidazoles, pyridines , tertiary amine Af-oxides ) acting as bases or as axial ligands on the metal catalyst. With the Mn-salen complex Mn-[AI,AI -ethylenebis(5,5 -dinitrosalicylideneaminato)], and in the presence of imidazole as cocatalyst and TBHP as oxidant, various alkenes could be epoxidized with yields between 6% and 90% (in some cases ionol was employed as additive), whereby the yields based on the amount of TBHP consumed were low (10-15%). Sterically hindered additives like 2,6-di-f-butylpyridine did not promote the epoxidation. 

Another type of steric effect is the result of an entropy effect. The compound 2,6-di-f-butylpyridine is a weaker base than either pyridine or 2,6-dimethylpyridine.113 The reason is that the conjugate acid (7) is less stable than the conjugate acids of non-sterically... 

AgOTf, 2,6-di-f-butylpyridine 1° alkyl iodide, PhCH2Cl, H2C=CHCH2Br TL 35 8111 (1994)... 

Enol tnflaies As a base for enoltriflation of quinolones 2-chloropyridine is adequate. It is a desirable substitute for 2,6-di-f-butylpyridine because the cost is decreased by 100-fold. 

Coupling with enol esters (7, 93). A new synthesis of an alkyl-substituted alkene involves coupling of a lithium dialkyl cuprate with an enol triflate,1 available from a ketone by reaction with triflic anhydride and 2,6-di-f-butylpyridine.2 A wide variety of organocuprates can be used and the geometry of the enolate is largely retained. Reported yields are in the range 60-100%. 

The hydroquinone produced from DDQ oxidations is fairly acidic and can interfere with acid sensitive glycals, but if the reaction is conducted in the presence of 2,6-di-f-butylpyridine glycals will survive. ... 

Large a-snbstitnents impede solvation of the protonated form 2,6-di-f-butylpyridine is less basic than pyridine by one p/faH nnit and 2,6-bis(tri-wo-propylsilyl)pyridine will not dissolve even in 6M hydrochloric acid. ... 

Etherification Various alcohols (primary, secondary, tertiary) can be etheri-fied with primary alkyl halides in a reaction mediated by AgOTf and the base 2,6-di-f-butylpyridine. 

Di-ferf-butylpyridine does not react at normal pressure, and this or 2,6-di-f-butyl-4-methylpyridine (synthesis ), are often used in applications which require base (see below). Note that 2,6-di-f-butylpyridine can be alkylated under high pressure with Me0S02p to give >90% of the methylation product when water is carefully excluded. ... 

Alcohols can be converted to methyl ethers hy the use of MeOTf + 2,6-di-f-butylpyridine or 2,6-di-f-butyl-4-methylpyridine. This procedure was initially developed in the carhohydrate field. Me3P04 provides a good polar solvent for this process. A recent application, in the synthesis directed at lonomycin, was to... 

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