Allyl bromide → Allylthio-2,6-dimethyl-4-heptanone

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Reaction Conditions

Reaction Steps

Into a 25 ml, round-bottom, three-necked flask equipped with magnetic stirrer, reflux condenser, nitrogen inlet tube and cold water bath is placed a solution of 0.162 grams (0.003 moles) of sodium methoxide dissolved in 2 ml anhydrous methanol. Using the water bath the temperature of the sodium methoxide solution is reduced to 23° C. At 23° C a solution of 0.522 grams (0.003 moles) of 3-mercapto-2,6-dimethyl-4-heptanone dissolved in 3 ml anhydrous methanol is added to the sodium methoxide solution. Subsequent to the addition of the mercapto ketone, after stirring for 15 minutes at 23° C, a solution of 0.40 grams (0.0033 moles) of allyl bromide dissolved in 2 ml anhydrous methanol is added to the reaction mass with stirring. The reaction mass warms to 33° C and is continued to be stirred at 25°-33° C for a period of 2 hours. It is concentrated on a rotary evaporator using water aspirator vacuum to a volume of 3 ml, thus yielding a white slurry. Eight ml water is then added to the slurry thereby dissolving the solid therein. One drop of 10% HCl is added to the resulting material thereby reducing the pH from about 9 to about 5. The reaction mass now existing in two phases is extracted with three 8 ml volumes of methylene chloride. The extracts are combined and washed with 6 ml water and then dried over anhydrous sodium sulfate, gravity filtered and concentrated on a rotary evaporator to a weight of 0.55 grams (pale yellow oil). GLC analysis (8' × 1/4" SE-30 column), NMR, IR and mass spectral analyses of GLC isolated material confirm that the resulting product is 97% product, 3-allylthio-2,6-dimethyl-4-heptanone, having the structure: ##STR66##

Provenance & Evidence