1065780-22-4Relevant academic research and scientific papers
Formation of intramolecular rings in ferramonocarbollide complexes
Franken, Andreas,Hodson, Bruce E.,McGrath, Thomas D.,Stone, F. Gordon A.
, p. 8788 - 8797 (2009/03/11)
Addition of PPh2Cl and Tl[PF6] to CH 2Cl2 solutions of [N(PPh3)2][6,6,6- (CO)3-closo-6,1-FeCB8H9] (1) affords the isomeric B-substituted species [6,6,6-(CO)3-n-(PHPh 2)-closo-6,1-FeCB8H8] [n = 7 (2a) or 10 (2b)]. Deprotonation (NaH) of the phosphine ligand in 2a, with subsequent addition of [IrCl(CO)(PPh3)2] and TI[PF6], yields the neutral, zwitterionic complex [6,6,6-(CO)3-4,7-μ-{Ir(H)(CO) (PPh3)2PPh2}-closo-6,1-FeCB8H 7] (3), which contains a B-P-Ir-B ring. Alternatively, deprotonation using NEt3, followed by addition of HC≡CCH2Br, affords [6,6,6-(CO)3-7-(PPh2C≡CMe)-closo-6,1- FeCB8H8] (4). Addition of [Co2(CO)8] to CH2Cl2 solutions of the latter gives [6,6,6-(CO) 3-7-(PPh2-{(μ-η2:η2- C≡CMe)Co2(CO)6})-closo-6,1-FeCB8H 8] (5), which contains a {C2Co2} tetrahedron. In the absence of added substrates, deprotonation of the PHPh2 group in compounds 2, followed by reaction of the resulting anions with CH 2Cl2 solvent, affords [6,6,6-(CO)3-n-(PPh 2CH2Cl)-closo-6,1-FeCB8H8] [n = 7 (6a) or 10 (6b)] plus [6,6-(CO)2-6,7-μ-{PPh2CH 2PPh2}-closo-6,1-FeCB8H8] (7, formed from 2a), of which the latter species possesses an intramolecular B-P-C-P-Fe ring. Addition of Me3NO to CH2Cl2 solutions of 2a causes loss of an Fe-bound CO ligand and formation of [6,6-(CO) 2-6,7-μ-{NMe2CH2PPh2}-closo-6,1- FeCB8H8] (8), which incorporates a B-P-C-N-Fe ring. A similar reaction in the presence of ligands L yields [6,6-(CO) 2-6-L-7-(PPh2CH2Cl)-closo-6,1-FeCB 8H8] [L = PEt3 (9) or CNBut (10)], in addition to 8.
