The formation of sulfur macrocycles containing dialkyne units

Treatment of the dialkyne complex [{Co-2(CO)(6)}(2){mu-eta(2):mu-eta(2)-HOCH2C=CC=CCH2OH}] with HBF4. OEt2 at -78 degrees C and the subsequent addition of [HS(CH2)(2)](2)X (X = S or O) affords the novel macrocyclic complexes [{Co-2(CO)(5)}{Co-2(CO)(6)}{(mu-eta(2)-C=CCH2SCH2CH2)(2)S}] 1a, [{Co-2(CO)(6)}(2){(mu-eta(2)-C=CCH2SCH2CH2)(2)O }] 2a and [{Co-2(CO)(6)}(2){(mu-eta(2)-C=CCH2SCH2CH2)(2)X}](2) [X = S 1b or O 2b].