Treatment of benzene solutions of [Pd(dba)₂](dba = dibenzylideneacetone) or [Pd(PPh₃)₄] with Ph₂PCH₂PPh₂(dppm) and X₂CCH₂(X = Cl or Br) gave the ‘A-frame’ vinylidene-bridged complexes of type [XPd(µ-dppm)₂(µ-CCH₂)PdX][X = Cl (1a) or Br (1b)] in high yield. Treatment of (1a), with LiBr, Nal, or KSCN in acetone gave [XPd(µ-dppm)₂(µ-CCH₂)PdX][X = Br (1b), I (1c), or NCS (1d)], respectively. Complex (1a) with TIO₂CMe gave [(MeCO₂)Pd(µ-dppm)₂(µ-CCH₂)Pd(O₂CMe)](1e) and with LiCCC₆H₄Me-4 the diacetylide complex [(p-MeC₆H₄CC)Pd(µ-dppm)₂(µ-CCH₂)Pd(CCC₆H₄Me-p)](2a) was obtained in low yield. Better yields of the diacetylides of type [(RCC)Pd(µ-dppm)₂(µ-CCH₂)Pd(CCR)] were obtained by treating (1a) with HCCR, TIPF₆, and NEt₃ in dichloromethane; e.g. with R = C₆H₄Me-4 (2a), Ph (2b), or CMe₂(OH)(2c). Treatment of (1a) with p-MeC₆H₄NC and NaBPh₄ in ethanol gave [(p-MeC₆H₄NC)Pd(µ-dppm)₂(µ-CCH₂)Pd(CNC₆H₄Me-p)][BPh₄]₂(3). Treatment of [Pd(PPh₃)₄] with dppm and Cl₂CCCl₂ gave a mixture of [ClPd(µ-dppm)₂(µ-CCCl₂)PdCl](4) and [ClPd(µ-dppm)₂PdCl] but (4) was obtained in high yield and purity when a mixture of [Pd(PPh₃)₄], dppm, and [PdCl(CClCCl₂)(PPh₃)₂] was heated. A mixture of [Pd(PPh₃)₄] and Ph₂PCHMePPh₂(mdppm) when treated with Cl₂CCH₂ gave the “A-frame” vinylidene-bridged complex [ClPd-(µ-mdppm)₂(µ-CCH₂)PdCl](5a) or (5b). Treatment of (1a) or (5a)/(5b) with HBF₄·Et₂O or CF₃CO₂H gave [ClPd(µ-L–L)₂(µ-CMe)PdCl]⁺[L–L = dppm (6) or mdppm (7)], characterized in solution by n.m.r. spectroscopy. Salts of these carbyne cations were not isolated pure. N.m.r. data are given and discussed.