2.6- Di-tert-butyl-4-methylpyridine

Addition of a bulky pyridine base Some workers have added an equivalent of 2,6-di-tert-butylpyridine or 2,6-di-tert-butyl-4-methylpyridine to the glycosylation mixture. While the reasons for this addition have not been discussed, one can note that according to a speculative equation for the glycosylation reaction ... 

A commercial sample of 2,6-di-tert-butyl-4-methylpyridine from Fluka AG was purified through a short column of silica gel by eluting with hexane. Alternatively it may be prepared according to the procedure reported in Organic Syntheses. ... 

Di-tert-butyl-4-methylpyridine Pyridine, 2,5-bis(l,1-dimethylethyl)-4-methyl- (9) (38222-83-2)... 

OTIPS (BrCl2C)2, PPI13, MeCN, 2,6-di-tert-butyl-4-methylpyridine... 

Mitsunobu Reaction for Exocyclic N2-Alkylation on a Purine Scaffold (Fig. 16).47 2,6-Di-tert-butyl-4-methylpyridine (1.54 g, 7.5 mmol, 0.3 M) is added to freshly distilled CH2C12 (25 ml) at 0° under N2. To this solution is added trifluoroacetic anhydride (706 pi, 5.0 mmol, 0.2 M) and the mixture is stirred for 5-10 min. The solution is then transferred to the resin 83 and the flask is vortexed and vented several times to relieve pressure. The flask is shaken for 6-12 h after which the solvent is removed and the resin washed with dry CH2C12 (5 x 25 ml) with vortexing between each rinse. The resulting resin 84 is dried. 

Heating the trifluoromethanesulfonate 89 in the presence of 2,6-di-tert-butyl-4-methylpyridine gave methyl 3,5-anhydro-2,6-dideoxy-/J-D-xylo-hexofuranoside 91. This rearrangement involves oxane-ring contraction 90 followed by internal sulfonate displacement.353... 

Both AgOTf and AgSbF6 (10mol%) were the best catalysts for this transformation, and the reaction was conducted in the presence of an hindered base, 2,6-di-tert-butyl-4-methylpyridine (DTBMP). The azomethine ylide CC intermediate has been identified in a test reaction in the absence of DMAD, via mass spectrometry. The scope and limitations have been thoroughly studied for reaching pyrroloisoquinoline scaffold, which is a substructure of the lamellarin alkaloid family. 

B. 2,6-Di-tert-butyl-4-methylpyridine (2). To 119-128 g (0.33-0.36 mol) of crude pyrylium salt in a 5-L, three-necked, round-bottomed flask equipped with a mechanical stirrer is added 2 L of 95% ethanol. The mixture is cooled to -60°C with an isopropyl alcohol-dry ice bath and to the fine slurry is added, with stirring, in one portion 1 L of concentrated (d 0.90) ammonium hydroxide also cooled to -60°C. The yellow reaction mixture is held at -60°C for 30 min, then allowed to warm to -40°C and maintained at that temperature for 2 hr, during which time the slurry dissolves. The mixture is then allowed to spontaneously warm to room temperature (Note 6). The reaction mixture is divided into two portions. Each portion is poured into a 4-L separatory funnel, 1 L of aqueous 10% sodium hydroxide is added, and the mixture is extracted with four 250-mL portions of pentane (Note 7). The extracts from both portions are combined and... 

C14H1806 (+)-(4,6-0-benzylidene)methyl-a-D-glucopyran 3162-96-7 25.00 1.2022 2 27723 C14H23N 2,6-di-tert-butyl-4-methylpyridine 38222-83-2 23.00 0.8979 2... 

Pyridine is added to neutralize small amounts of hydrogen iodide, which is often present in iodotrimethylsilane as a result of hydrolysis by contact with moisture. The amount of by-products, including cyclohexyl iodide, is reduced by the presence of pyridine. Hindered pyridine bases such as 2,6-di-tert-butyl-4-methylpyridine" have also been used for this purpose by the submitters. The pyridine bases do not appear to react with iodotrimethylsilane. 

BCI3, toluene, 2,6-di-tert-butyl-4-methylpyridine, —78"C, 87% yield. In the synthesis of ditriptophenaline, an FMOC group did not survive the basic TBAF or BF3-Et20. ... 

Proton Traps. 2,6-Di-tert-butyl-4-methylpyridine (DBMP) and 2,6-di-tert-butyIpyridine (DtBP) are hindered bases incapable of reacting with electrophiles other than protonic acids. Consequently, they can be successfully used for the trapping of protons during their transfer to monomer (174. 175). At the same time they can disseminate between the two major initiation mechanisms encountered in cationic polymerization, that is, protonic initiation or carbenium initiation (176). 

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