X-Ray crystal structure of a unique cyano-bridged cyclic palladium(II) trimer

Abstract

The crystal structure of [Pd₃(dppe)₃(µ-CN)₃][ClO₄]₃(dppe = Ph₂PCH₂CH₂PPh₂) is reported. The complex crystallizes in the trigonal space group R with unit-cell parameters a= 22.737(3)Å, α= 40.288(4)°, and Z= 6. The final R index was 0.052 using 1 495 independent reflections in the least-squares refinement. The structure is based on a Pd₃(µ-CN)₃ cyclic trimer unit and ³¹P n.m.r. indicates an unsymmetrical arrangement of the cyano-bridges. The angles Pd–C–N = 165(2) and Pd–N–C = 164(1)° make the cyano-bridge significantly non-linear at both ends. There are seven perchlorate sites within the unit cell, two of which are only partially occupied.