Sodium ferf-butoxide

Some breakthrough was finally achieved by using Pd2(dba)3 as the Pd complex, tris(tert-butyl)phosphine as the ligand, and sodium ferf-butoxide as the base [90]. This combination of reagents proved to bring about the synthesis of unsubstituted phenazine (137) by reaction of two molecules of 2-bromoaniline (131). Remarkably, no reaction takes place under the conditions of the 133 117 transformation. Currently the scope and limitations of this new sequential inter-Zintramolecular AT-arylation for the synthesis of AT-heterocycles... 

Thus reactions of a primary halide (Following fig.) with an ethoxide ion is likely to give a mixture of an ether arising from Sn2 substitution along with an alkene formed by E2 elimination, with the ether being favoured. By using sodium ferf-butoxide instead, the preferences would be reversed. 

Representative Procedure for the Palladium-Catalyzed Arylation of Amines with Aryl Bromides using DPPF/Pd (Excerpted with permission from [29]. 1996 American Chemical Society) In an inert atmosphere dry box, DPPFPdClj and 3.0 equiv. of DPPF/Pd were added to a solution of 20 equiv of bromoben-zophenone and 25 equiv of sodium ferf-butoxide in 8 ml of anhydrous THF. The reaction tube was sealed with a cap containing a PTFE septum and removed from the dry box. Butylamine (25 equiv) was added to the reaction mixture by syringe, and the mixture was heated to 100 °C for 3 h. The reaction was cooled to room temperature, the volatile materials were removed by rotary evaporation, and the product was isolated by either sublimation or silica-gel chromatography (20 1 hexane/EtOAc or 10 1 hexane/Et20 followed by 4 1 hexane Et20). 

General Procedure for the N-Arylation of Indoles (Excerpted with permission from [119]. 2000 American Chemical Society) A Schlenk tube was charged with sodium ferf-butoxide (1.4 mmol), Pd2(dba)3 (0.005 mmol), and 4 (0.015 mmol). The Schlenk tube was fitted with a septum and attached to a Schlenk line. After the air atmosphere was replaced with argon, toluene (2 ml), aryl bromide (1.0 mmol), and the indole (1.2 mmol) were added. After the septum was replaced with a teflon valve, the reaction was sealed and heated to 80- 100°C with stirring until starting material was consumed as judged by GC analysis. The reaction mixture was cooled to room temperature, diluted with ether (20 ml), filtered, and concentrated. The crude reaction mixture was then purified by flash chromatography on silica gel. 

Ferrocene-based phosphine 24 is also an effective supporting ligand for the Pd-catalyzed condensation of chloroarenes and sodium ferf-butoxide [148]. The coupling of 2-chloro-para-xylene, followed by acid mediated cleavage of the ferf-butyl group, yielded the desired phenol in 71 % yield, Eq. (190). 

Sodium ferf-butoxide in N,N-dimethylformamide at KXP was found to be very effective in promoting intramolecular displacements408 and 2,5 -anhydrothymidine was obtained directly from 5 -0-(methyl-sulfonyl)thymidine with these reagents. The same conditions have also been used to synthesize the anhydronucleosides 121 and 122 from a pseudouridine derivative408 and from a D-ribosyl derivative of 2,4-quinazolinedione.410 The same reagents with 3 -0-p-tolylsulfonyl-uridine gave mainly 1 -(2,3 -anhydro-y3-D-xylofuranosyl)uracil.408... 

The Buchwald-Hartwig amination is an exceedingly general method for generating any type of aromatic amine from an aryl halide or aryl sulfonates.1,2 The key feature of this methodology is the use of catalytic palladium modulated by various electron-rich ligands. Strong bases, such as sodium ferf-butoxide, are essential for catalyst turnover. 

In Michaelis-Becker reactions between 2- or 3-(chloromethyl)furans and NaOP(OMe)2 in MeOH both the methoxymethyl derivatives and phosphonic diesters are produced, the latter in smaller proportions. Sodium ferf-butoxide affords even poorer yields of phosphonate esters but also less of the ethers. ... 

The chiral E-R -9-BBN alkylates the chloroacetonitrile to afford in good yields the corresponding chiral nitriles. Sodium ferf-butoxide in THF is best suited for the a-alkylation of chloroacetonitrile (Eq. 10.4) [4]. 

In 1999, Watanabe et al. showed that the catalyst derived from Pd(OAc)j and P(fBu)3 functions as a very efficient system for the etherification of aryl halides with sodium-ferf-butoxide [68]. Both electron-deficient and electron-rich aryl halides could be successfully used, and the first synthesis of 4-chlorobenzofuran was obtained by the selective mono-fert-butoxylation of an aryl halide. 

Amination of aryl chlorides is possible using PdCl2(PCy3)2 as a catalyst. The reactions are run in toluene as a solvent and with sodium ferf-butoxide as base. Buchwald has used a range of (o-biphenyl)PCy2 ligands for the same reaction. ... 

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