Improved synthesis of halo- and oxonium derivatives of dodecahydrido‑closo-dodecaborate(2-)

Facile Attachment of Halides and Pseudohalides to Dodecaborate(2-) via Pd-catalyzed Cross-Coupling

“…Previously, [B 12 H 11 I] 2− was reacted under Kumada coupling conditions with Grignard reagents [ 17 , 18 ]. The procedure to introduce an iodine atom into the [B 12 H 12 ] 2− cluster could be improved considerably by using not molecular iodine, but N-iodosuccinimide, resulting in very clean stoichiometric iodinations [ 19 ]. The corresponding N-chloro- and N-bromosuccinimides result in the corresponding chloro- and bromododecaborates, again in clean reactions with well-controllable stoichiometry.…”

Alkoxy Substituted Brominated closo-Dodecaborates with Functionalized Aliphatic Spacers

“…A dodecaborate containing a cyclic oxonium group, [B12Br11O(CH2)4] 2-2, can be obtained on a gram scale in a single step in a moderate yield without the formation of over hydroxylated byproducts. [11] We supposed that the acid-mediated rupture of the C-O bond of 2 during the bromination step would generate highly pure 3. Thus, 2 was prepared according to a reported method (Fig.…”

“…All the [B12Br11OR] 2species with functionalized aliphatic spacers show a 1:10:1 pattern in their 11 B NMR spectra and the chemical shift is independent of the terminal substituent (ESI Figure 3-10). Likewise, in the 1 H NMR spectra, the terminal substituent does not change the chemical shift of the signal for the -CH2-O-B12 peak.…”

Carboxonium derivatives based on closo-dodecaborate anions [1,2-B12H10O2CR]−: synthesis and molecular orbital analysis

“…18 Such complexes have been obtained for closo-borate anions and nidocarborane as well as for cobalt and iron bis(dicarbollides). [19][20][21] Cyclic ethers such as tetrahydrofuran, tetrahydropyran and dioxane act as donors. The interest in oxonium boron derivatives is driven by the potential for further functionalisation of these molecular systems.…”