Stereoselective double functionalization of iron-carbonyl complexes of 5,6,7,8-tetramethylidenebicyclo[2.2.2]oct-2-ene. Crystal structure and absolute configuration of (-)-trans-m-[(2S,5R,7S)-C,5,6,C-h:C,7,8,C-h-(6,7,8-trimethylidene-5-((Z)-2-oxopropylidene)-2-bicyclo[2.2.2]octyl acetate)]bis(tricarbonyliron)