Synthesis and characterization of new 10- and 12-vertex CO-ligated metallathiaboranes

Abstract

Dedicated to Professor Thomas P. Fehlner on his 75th birthday. He has been a superb mentor of many scientists around the world working on "inorganometallic chemistry". Keywords:The reaction between [arachno-6-SB 9 H 12 ] À and [IrCl(CO)(PMe 3 ) 2 ] affords the previously reported 11-vertex cluster, [8,8,(PMe 3 ) 2 -arachno-8,7-IrSB 9 H 10 ] (4), and small amounts of the new 10-vertex iridathiaborane [9,9,9,(H)(PMe 3 ) 2 -arachno-9,6-IrSB 8 H 10 ] (5). Alternatively, a rational synthesis of iridathiadecaboranes is effected from the reaction of the 9-vertex anion [arachno-4-SB 8 H 11 ] À with [MCl(CO)(PPh 3 ) 2 ], to afford new CO-ligated 10-vertex metallathiaboranes of formulation, [9,9,9,(H)(PPh 3 ) 2 -arachno-9,6-MSB 8 H 10 ], where M ¼ Rh (6) and Ir (7), in useful yields of 61% and 60% respectively. Treatment of the 11-vertex rhodathiaborane, [8,8-(PPh 3 ) 2 -8,7-nido-RhSB 9 H 10 ] (1) with nBuLi, followed by addition of [IrCl(CO)(PMe 3 ) 2 ] affords the 12-vertex iridarhodathiaborane, [1,2-(m-CO)-1,1,2-(PMe 3 ) 3 -2-(PPh 3 )-closo-1,2-IrRhSB 9 H 9 ] (8) in low yield (0.7%). The 10-vertex metallathiaboranes, 5, 6 and 7, and the bimetallic 12-vertex cluster, 8, have been characterized by multinuclear NMR spectroscopy. In addition, the molecular structures of compounds 5, 6, and 8 have been studied by X-ray diffraction.

Reactions of 11-Vertex Rhodathiaboranes with HCl: Synthesis and Reactivity of New Cl-Ligated Clusters

“…A general characteristic of boranes, heteroboranes, and their metal derivatives metallaboranes and metallaheteroboranes, is that B–H–B bridging hydrogen atoms are relative acidic. This allows, for example, the deprotonation of polyhedral boron-containing compounds such as nido -B 10 H 14 , arachno -4-CB 8 H 14 , arachno -4-SB 8 H 12 , nido -4-NB 9 H 12 , [8,8-(PPh 3 ) 2 - nido -8,7-RhSB 9 H 10 ], or [8,8-(PMe 2 Ph) 2 - nido -8,7-PtB 10 H 12 ] by treatment with the strong bases. Following this approach, the reaction of the rhodathiaborane, 3 , with the non-nucleophilic base N , N , N ′, N ′-tetramethylnaphthalene-1,8-diamine, commonly known as Proton Sponge (PS), in dichloromethane afforded small amounts of the bis-PPh 3 -ligated closo -parent cluster, 2 , and the salt [PSH]Cl.…”