Isomeric commo‐Ferracarboranes: meso‐, dd/ll‐[PPh₃R][commo‐Fe(2,4‐closo‐C₂B₈H₁₀)₂] and Their Bimetal Ferra–Copper Zwitterion Derivatives

Abstract

] (meso, R = Me: 1a; meso, Et: 1b; DD/LL, R = Me: 2a; DD/LL, R = Et: 2b) with unusual closo geometry. Both DD/LL and meso isomers were successfully isolated and their structures were determined using single-crystal X-ray diffraction studies. Their paramagnetic properties were confirmed with EPR spectra and their oxidative-reductive properties were

New 11-vertex osmacarborane 1,1-(PPh3)2-1-H-3-O(CH2)4-isonido-1,2,4-OsC2B8H9

“…The downfi eld signal at δ = 62.5 belongs to the boron atom possessing a low intercluster coordination number, which is the distinguishing feature of well-known 11-vertex isonidoclusters containing {C 2 B 8 } carborane ligands. [17][18][19][20][21][22][23][24][25] In the 11 В{ 1 H} and 11 B NMR spectra of complex 3, such a signal appears as the singlet, indicating the presence of a substituent at this boron atom, which usually occupies the B(3) position in the {M-C 2 B 8 } metallacarborane moiety. Two slightly broadened singlets at δ = 2.68 and 1.42 with the intensity of 1 H each in the 1 H NMR spectrum of complex 3 correspond to hydrogen atoms of the cluster CH groups.…”