Potassium ferf-butoxide-dimethyl sulfoxide

Similarly, sodium methoxide (NaOCHj) is a suitable base and is used in methyl alcohol. Potassium hydroxide in ethyl alcohol is another base-solvent combination often employed in the dehydrohalogenation of alkyl halides. Potassium ferf-butoxide [K0C(CH3)3] is the prefened base when the alkyl halide is primary it is used in either terf-butyl alcohol or dimethyl sulfoxide as solvent. 

B. Benzocyclopropene. A dry, three-necked, round-bottomed flask fitted with a sealed mechanical stirrer, a reflux condenser, and a pressure-equalizing dropping funnel is flushed with nitrogen. To the flask is added 35.0 g (0.312 mole) of potassium ferf-butoxide (Note 1), followed by 200 ml. of dimethyl sulfoxide (Note 5). The stirred mixture is cooled to 15-20° (Note 6) with an ice bath and 24.5 g. 

A previous method [1] of preparing 3,3-dimethylbutyne by dehydrochlorination of the title compound in a sodium hydroxide melt is difficult to control and hazardous on the large scale. Use of potassium ferf-butoxide as base in DMSO is a high-yielding, safe and convenient alternative method of preparation of the alkyne [2], See Dimethyl sulfoxide Metal alkoxides See other HALOALKANES... 

Compounds A and B are isomers of molecular formula C9H19Br. Both yield the same alkene C as the exclusive product of elimination on being treated with potassium ferf-butoxide in dimethyl sulfoxide. Hydrogenation of alkene C gives 2,3,3,4-tetramethylpentane. What are the structures of compounds A and B and alkene C ... 

Potassium ferf-butoxide reacts with halobenzenes on heating in dimethyl sulfoxide to give ferf-butyl phenyl ether. 

A high concentration of a strong base in a relatively nonpolar solvent is used to carry out the dehydrohalogenation reaction. Such combinations as sodium methoxide in methanol, sodium ethoxide in ethanol, potassium isopropoxide in isopropanol, and potassium ferf-butoxide in fcrf-butanol or dimethyl sulfoxide (DMSO) are often used. 

---