Cork, boring

Small discs (about 15 mm in diameter) were cut from the agar using a cork-boring machine. 

Freshly opened cans of anhydrous ether (Fisher) were used in the extraction process. Efficient drying over MgSC>4 (under nitrogen) is needed to avoid excessive loss of product in the forerun as a product/water azeotrope. The one-hole rubber septum used for ihe transfer process was obtained by using a cork bore of the appropriate size on a 24/40 rubber septum (Aldrich Chemical Company, Inc.). Rotary evaporation to remove the ether was carried out at 200-300 mbar (150-225 mm)... 

The stoppers in the reaction flask and at the top of the dropping funnel are of rubber the other two are well-selected corks, bored perfectly and painted both inside and out with water-glass, one day previous to being used. 

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