Note.

The reaction of octacarbonyldicobalt and dipropargyl terephthalate gave the two expected compounds [C 6 H 4 -1,4-(CO 2 CH 2 C 2 H-μ) 2 ][Co 2 (CO) 6 ] 2 (1) and [ p -(HC 2 CH 2 OCO)C 6 H 4 (Co 2 CH 2 C 2 H-μ)][CO 2 (CO) 6 ] (2). Both (1) and (2) were characterized by elemental analysis, IR and NMR spectra. The molecular structure of (2) was established by single-crystal X-ray diffraction methods. [ABSTRACT FROM AUTHOR]