MIGRATION OF DOUBLE BONDS 189 In both of the above cases the aluminum isopropoxide was prepared from aluminum metal amalgamated with a small amount of mercuric chloride, and was used without purification. Such an unpurified solu-tion has been used successfully in many instances and excellent yields of the alcohol have been obtained. However, in these special cases in which the alcohols are sensitive to dehydration it is preferable to use distilled aluminum isopropoxide; inconsistent yields and an impure product were obtained when 4'-ketotetrahydro-3,4-benzpyrene (XXXIII) was reduced with unpurified reagent, but with distilled reagent the yield of the alcohol was always in the range 79-90%. 31 CH 8 XXXIII XXXIV XXXV Migration of Double Bonds. It has been assumed by many workers that carbon-carbon double bonds are unaffected by aluminum iso-propoxide. Although it is true that these double bonds are not reduced, yet in several instances reduction of an unsaturated ketone has resulted in a shift of the double bond as well as reduction of the carbonyl group.
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This note was uploaded on 11/20/2011 for the course CHM 2210 taught by Professor Reynolds during the Fall '01 term at University of Florida.