Reductive Coupling of Carbonyls to Alkenes Adamantylideneadamantane

Submitted by Michael P Fleming and John E McMurry1 Checked by Steven R Villasenor and Carl R Johnson 

Stirring is maintained as the mixture is allowed to cool to room temperature, and 600 mL of petroleum ether (Note 7) is added in 100-mL portions at 5-min intervals (Note 9). The stirrer is disconnected from its motor, and the solution is poured into a sintered-glass funnel containing 50 g of Florisil (approximately 7 cm in 

The following reagents were used as supplied titanium trichloride from Alfa Products, Ventron Corporation 2-adamantan-one from Aldrich Chemical Company, Inc. methanol from Mathe-son, Coleman and Bell and acetone from Mallinckrodt, Inc. 

Because of its sensitivity toward oxygen and water, anhydrous titanium trichloride should always be handled under an inert atmosphere. The submitters report that titanium trichloride in bottles that have been opened and resealed undergoes a slow deterioration that causes erratic results in the coupling reaction. This decomposition is frequently detectable by the evolution of white fumes from the titanium trichloride during transfer. If a number of small-scale reactions are to be performed, the use of a Schlenk tube is advisable to extend the useful life of the titanium trichloride. 

Substitution of nitrogen for argon does not significantly decrease the yield. 

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