The tetrahedral cluster [RUCo3(CO)(12)](-) reacts with various alkynes, including the new PhC equivalent to CC(O)NHCH2C equivalent to CH (L-1), to afford the butterfly clusters [RuCo3(CO)(10)(mu(4)-eta(2)-RC2R')](-) (1, R = R' C(O)OMe; 2, R = H, R' = Ph; 3, R = H, R' = MeC = CH2; 4, R = H, R' = CH2OCH2C equivalent to CH; 5, R = H, R' = CH2NHC(O)C equivalent to CPh), in which the ruthenium atom occupies a hinge position and the alkyne is coordinated in a mu(4)-eta(2) fashion. Reaction of the anions 1-3 with [Cu(NCMe)(4)]BF4 led to selective loss of the 12e fragment Co(CO)(-) to form [RuCo2(CO)(9)(mu(3)-eta(2)-RC2R')] (6, R = R' = C(O)OMe; 7, R = H, R' = Ph; 8, R = H, R' = MeC = CH2). To prepare functionalized RuCo3 or FeCo3 clusters that could be subsequently condensed with a silica matrix via the sol-gel method, we reacted [MCo3(CO)(12)](-) (M = Ru, Fe) with the alkyne PhC equivalent to CC(O)NH(CH2)(3)Si(OMe)3 (L-2) and obtained the butterfly clusters [MCo3(CO)(10)(mu(4)-eta(2)-PhC2C(O)NH(CH2)(3)Si(OMe)(3))](-) 9 and 10, respectively. Air-stable [RuCo3(CO)(10)(mu(4)-eta(2)-Me3SiC2C equivalent to CSiMe3)](-) (11) was obtained from 1,4-bis(trimethylsilyl)butadiyne and reacted with [Cu(NCMe)(4)]BF4 to give [RuCo2(CO)(9)(mu(3)-eta(2)-HC2C = CSiMe3)] (12), owing to partial ligand proto-desilylation, and not the expected (RuCo2(CO)(9)(mu(3)-eta(2) -Me3SiC2C equivalent to CSiMe3)]. Reaction of 11 with [NO]BF4 afforded, in addition to 12, [RuCo3(CO)(9)(NO)(mu(4)-eta(2)Me(3)SiC(2)C equivalent to CSiMe3)] (13) owing to selective CO substitution on a wing-tip cobalt atom with NO. The thermal reaction of 11 with [AuCl(PPh3)] led to replacement of a CO on Ru by the PPh3 originating from [AuCl(PPh3)] and afforded [RuCo3(CO)(9)(PPh3)(mu(4)-eta(2)-Me3SiC2C equivalent to CSiMe3)](-) (14), also obtained directly by reaction of 11 with one equivalent of PPh3. Proto-desilylation of 11 using TBAF/THF-H2O afforded [RuCo3(CO)(10)(mu(4)-eta(2)-Me3SiC2C equivalent to CH)](-) (15) which, by Sonogashira coupling with 1,4-diiodobenzene, yielded the dicluster complex [{[RuCo3(CO)(10)(mu(4)-eta(2)-Me3SiC2C equivalent to C)]}(2)C6H4](2-) (16). The crystal structures of NEt4.3a, NEt4.4a, 6, NEt4.11b, NEt4.14, and [N(n-Bu)(4)].15a have been determined by X-ray diffraction. Preliminary results indicate the potential of sHica-tethered alkyne mixed-metal clusters, obtained by the sol-gel method, as precursors to bimetallic particles.