1. Transition Metal Alkyne Complexes: Pauson–Khand Reaction
2. Titanocene-catalyzed conversion of enynes to bicyclic cyclopentenones
3. Optisch aktive Übergangsmetall-Komplexe
4. Ansa-metallocene derivatives
5. General Procedure: In an argon filled glovebox, a dry sealable Schlenk flask is charged with (S,S)-(EBTHI)TiMe2(0.025 mmol, 8 mg), toluene (2 mL), and the substrate (0.50 mmol). The Schlenk is removed from the glovebox, attached to a Schlenk line, evacuated, and backfilled with 14 psig CO.Caution:Appropriate precautions should be taken when performing reactions under elevated CO pressure. The reaction mixture is heated to 90 °C for 12−16 h. After cooling the reaction mixture to room temperature, the CO is cautiously released in the hood. The crude reaction mixture is filtered through a plug of silica gel with the aid of diethyl ether and purified by flash chromatography.Note:All substrates were passed through a plug of alumina (except for entry 1) in the glovebox to remove adventitious moisture. The substrate for entry 1 was distilled under vacuum and stored in the glovebox.