Macropolyhedral boron-containing cluster chemistry. The reaction of B₁₆H₂₀and B₁₄H₁₈with [PtMe₂(PMe₂Ph)₂] to give [(PMe₂Ph)₂PtB₁₆H₁₇Me] and [(PMe₂Ph)₂PtB₁₄H₁₆]

Abstract

Structurally characterised 17-vertex [(PMe2Ph)2PtB16H17Me] 3 is obtained, albeit in low yield, by platination of 16-vertex B16H20 1 using [PtMe2(PMe2Ph)2] under mild conditions. Platination has occurred on the {B10} subcluster of 1, interesting in that B16H20 itself deprotonates on the {B8} subcluster: the reference 16-vertex [B16H19]- anion 1a, prepared by deprotonation of 1 with 1,8-bis(dimethylamino)naphthalene, is also structurally characterised. [PtMe2(PMe2Ph)2] with 14-vertex B14H18 2 similarly gives a low yield of 15-vertex [(PMe2Ph)2PtB14H16] 5, of formulation and structure substantiated by DFT calculations.

Macropolyhedral boron-containing cluster chemistry. An unusual ‘neonido ’ ten-vertex subcluster configuration in a [(PPh3)2RuB16H20] species

“…It will also be of interest to ascertain whether products resulting from the addition of the ruthenium centre to the {B 10 } subcluster of B 16 H 20 also occur. In this last regard, the ruthenaborane 1 reported here contrasts to the only other B 16 H 20 -derived metallaborane reported, [(PMe 2 Ph) 2 PtB 16 H 17 Me] (compound 3) of schematic skeletal configuration VIB, obtained using [PtMe 2 (PMe 2 Ph) 2 ] as the cluster-metallating reagent [12]. In this latter platinum compound 3, the metal atom has added to an alternative open face site on the other, nido-decaboranyl, subcluster of the starting B 16 H 20 substrate (hatched lines in schematic VIB).…”

“…The compound is isolated from the reaction between B 16 H 20 and [RuCl 2 (PPh 3 ) 3 ] in the presence of the non-nucleophilic base 1,8-bis(dimethylamino)naphthalene. Although B 16 H 20 has been known for some time, [10,11], its reaction chemistry is essentially unexamined [12]. Fig.…”

Macropolyhedral boron-containing cluster chemistry. The reversible disassembly and reassembly of the hexagonal pyramidal {B7} feature in the [S2B18H19]− anion

“…35,36 With twenty nonhydrogen atoms, the thirty-nine-atom anion 1 is the largest boroncontaining cluster to be successfully calculated in this manner. At the time of these calculations, previously published limits were in the region of ten non-hydrogen cluster atoms, 18,37,38 This result therefore engendered a general confidence in this DFT B3LYP/6-31G*/GIAO approach for tackling the crystallographically unsubstantiated The first unknown {S 2 B 18 } molecule to be tackled was the neutral species 4, which NMR had previously suggested was of arachno-ten-vertex:nido-eleven-vertex character for which a two-borons-in-common skeletal structure IVA had been initially proposed. 15 Energetic minimisation at B3LYP/6-31G*, however, gave a somewhat different structure (Fig.…”

Borane reaction chemistry. Alkyne insertion reactions into boron-containing clusters. Products from the thermolysis of [6,9-(2-HCC–C5H4N)2-arachno-B10H12]

“…However, little is known about the reaction coordinate of this process, beyond that the first step is a dissociation of one ligand residue, to give a 'reactive' {LB 10 H 12 } isomer. 28, 30 The actual alkyne insertion step is not elucidated, although work on other alkynyl group insertions on boron-containing clusters other than ten-vertex {B 10 } species [18][19][20][21][22]31 suggests that models for a continuum of intermediates may be isolatable by choice among appropriate systems. In our present case, we surmised that a competition between the Lewis base [ortho-(HC≡C)-C 5 H 4 N] and its properties as an alkyne ready for insertion into the B 10 H 14 had to exist, and this warranted investigation: part of this further work is described in this present paper.…”