Treatment of 0.5 equiv of [(CpIrCl2)-Ir-star](2) with 1/3-(PPr2)-Pr-i-2-(SBu)-Bu-t-indene afforded (CpIr)-Ir-star(Cl)(kappa(2)-3-P(i)Pr(2)2-S-indene) (1) in 95% yield (Cp-star = eta(5)-C5Me5). Addition of AgOTf or LiB(C6F5)(4)center dot 2.5OEt(2) to 1 gave [(CpIr)-Ir-star(kappa(2)-3P(i)Pr(2)-2-S-indene)]X-+(-) ([2]X+; X = OTf, 78%; X = B(C6F5)(4), 82%), Which represent the first examples of isolable coordinatively unsaturated [Cp'Ir(kappa(2)-P,S)]X-+(-) complexes. Exposure of [2]+OTf- to CO afforded [2 center dot CO]+OTf-in 91% yield, while treatment of [2]B+(C6F5)(4)(-) with PMe3 generated [2 center dot PMe3]B+(C6F5)(4)(-) in 94% yield. Treatment of 1 with K2CO3 in CH3CN allowed for the isolation of the unusual adduct 3 center dot CH3CN (41% isolated yield), in which the CH3CN bridges the Lewis acidic (CpIr)-Ir-star and Lewis basic indenide fragments of the targeted coordinatively unsaturated zwitterion (CpIr)-Ir-star(kappa(2)-3-(PPr2)-Pr-i-2-S-indenide) (3). In contrast to the formation of [2 center dot CO]+OTf-, exposure of 3 center dot CH3CN to CO did not afford 3 center dot CO; instead, a clean 1:1 mixture of (kappa(2)-3-(PPr2)-Pr-i-2-S-indene)Ir(CO)(2) (4) and 1,2,3,4-tetramethylfulvene was generated. Treatment of [2]+OTf- with Ph2SiH2 resulted in the net loss of Ph2Si(OTf)H to give (CpIr)-Ir-star(H)(kappa(2)-3-(PPr2)-Pr-i-2-S-indene) (5) in 44% yield. In contrast, treatment of [2]B+(C6F5)(4)(-) with Ph2SiH2 or PhSiH3 proceeded via H-Si addition across Ir-S to give the corresponding [(CpIr)-Ir-star(H)(kappa(2)-3-(PPr2)-Pr-i-2-S(SiHPhX)-indene)]B+(C6F5)(4 )(-) complexes 6a (X = Ph, 68%) or 6b (X = H, 77%), which feature a newly established S-Si linkage. Compound 6a was observed to effect net C-O bond cleavage in diethyl ether with net loss of Ph2Si(OEt)H, affording [(CpIr)-Ir-star(H)(kappa(2)-3-(PPr2)-Pr-i-2-SEt-indene)]B+(C6F5)(4)(-) (7) in 77% yield. Furthermore, 6a proved capable of transferring Ph2SiH2 to acetophenone, with concomitant regeneration of [2]B+(C6F5)(4)(-); however, [2]X-+(-) did not prove to be effective ketone hydrosilylation catalysts. Treatment of 1/3-(PPr2)-Pr-i-2-(SBu)-Bu-t-indene with 0.5 equiv of [(CpRhCl2)-Rh-star](2) gave (CpRh)-Rh-star(Cl)(kappa(2)-3-(PPr2)-Pr-i-2-S-indene) (8) in 94% yield. Combination of 8 and LiB(C6F5)(4)center dot 2. 5Et(2)O produced the coordinatively unsaturated cation [(CpRh)-Rh-star(kappa(2)-3-(PPr2)-Pr-i-2-S-indene)B+(C6F5)(4)(-) ([9]B+(C6F5)(4)(-)), which was transformed into [(CpRh)-Rh-star(H)(kappa(2)-3-(PPr2)-Pr-i-2-S(SiHPh2)-indene)]B+(C6F5)(4 )(-) (10) via net H-Si addition of Ph2SiH2 to Rh-S. Unlike [2]X-+(-), complex [9]B+(C6F5)(4)(-) was shown to be an effective catalyst for ketone hydrosilylation. Treatment of 3 center dot CH3CN with Ph2SiH2 resulted in the loss of CH3CN, along with the formation of (CpIr)-Ir-star(H)(kappa(2)-3-(PPr2)-Pr-i-2-S-(1-diphenylsilylindene)) (11) (64% isolated yield) as a mixture of diastereomers. The formation of 11 corresponds to heterolytic H-Si bond activation, involving net addition of H- and Ph2HSi+ fragments to Ir and indenide in the unobserved zwitterion 3. Crystallographic data are provided for 1, [2 center dot CO]+OTf-, 3 center dot CH3CN, 7, and 11. Collectively, these results demonstrate the versatility of donor-functionalized indene ancillary ligands in allowing for the selection of divergent metal-ligand cooperativity pathways (simply by ancillary ligand deprotonation) in the activation of small molecule substrates.