text: Organobarium compounds of the type (allyl)BaCl can be prepared by reaction of activated barium (Rieke method reduction of barium iodide with lithium biphenylide) with allyl halides. These allylbarium compounds react with carbonyl compounds.  Such reagents are more alpha-selective and more stereoselective than the related Grignards or organocalcium compounds. The metallocene (Cp*)Ba has also been reported.