figures 5r methyl 2 phenylsulfinylcyclohexanone 1 7 14 g 30 0 mmoles in dry thf 75 ml at 30 u00b0 c under argon was treated with a solution of lithium diisopropylamide prepared from 9 ml or 64 5 mmoles of diisopropylamine and 41 6 ml of 1 55m solution of n buli in hexane in dry thf 75 ml followed by dry hexamethylphosphoramide hmpa 30 ml the mixture was stirred at 30 u00b0 c for 3 hr and then 2 2 39 bromoethyl 2 5 5 trimethyl 1 3 dioxane 2 8 42 ml 36 0 mmoles was added dropwise via syringe the mixture was stirred at 30 u00b0 c for 1 hr and then was allowed to warm to room temperature over 1 hr the mixture was poured into ice cold saturated ammonium chloride solution 100 ml and was extracted with diethyl ether 2 u00d7 100 ml the organic layers were washed with water 3 u00d7 100 ml and brine 100 ml dried mgso 4 and evaporated in vacuo to give 15 1 g of crude alkylation product 3 this was dissolved in thf 675 ml to which was added water 75 ml followed by 7 5 g of amalgamated aluminum foil strips prepared by dipping aluminum foil strips in 2 aqueous mercuric chloride for 15 sec followed by washing with absolute ethanol and diethyl ether the mixture was stirred at room temperature for 2 hr and then was filtered under reduced pressure while the solids were being washed with diethyl ether 500 ml the filtrate was washed with 5 sodium hydroxide solution 3 u00d7 500 ml water 500 ml and brine 500 ml the aqueous phases were.