Postsynthetic modifications of [2,2,2-(H)(PPh3)2-closo-2,1-RhSB8H8] with lewis bases: cluster modular tuning
Resumen: It has been demonstrated that the reaction of [2,2,2-(H)(PPh3)2-closo-2,1-RhSB8H8] (1) with PPh3 affords the boron substituted rhodathiaborane–PPh3 adduct, [6,6-(PPh3)2-9-(PPh3)-arachno-6,5-RhSB8H9] (2). Building upon this reaction, we report herein that the 10-vertex hydridorhodathiaborane 1 reacts with the Lewis bases, PCy3, py, 2-Mepy, 2-Etpy, 3-Mepy and 4-Mepy to form the rhodathiaborane–ligand adducts, [6,6-(PPh3)2-9-(L)-arachno-6,5-RhSB8H9], where L = PCy3 (3), 2-Mepy (4), 2-Etpy (5), py (6a), 3-Mepy (7a) or 4-Mepy (8a), and [8,9-µ-(H)-9-(PPh3)2-8-(L)-arachno-9,6-RhSB8H8], where L = py (6b), 3-Mepy (7b) or 4-Mepy (8b). The selectivity of the reactions depended on the nature of the entering Lewis bases, affording the 6,5-isomers, 2, 3, 4 and 5 as single products for PPh3, PCy3, 2-Mepy and 2-Etpy; and mixtures of the 6,5-/9,6-regioisomers, 6a/6b, 7a/7b and 8a/8b for py, 3-Mepy and 4-Mepy, respectively. The molecular structures of both regioisomers were characterized by X-ray diffraction analysis for the 6,5-isomers, 3 and 4, and for the 9,6-isomers, 7b and 8b. Variable temperature NMR studies of the reaction between 1 and PPh3 or 2-Mepy demonstrated that at low temperatures there is formation of the 9,6-species that subsequently isomerizes to the 6,5-regioisomer, indicating that for the more sterically hindered Lewis bases, PPh3, 2-Mepy and PCy3, the latter isomer is more stable and accessible through an intramolecular {Rh(PPh3)2} vertex flip. The formation of both isomers with py, 3-Mepy and 4-Mepy indicates that the kinetic and thermodynamic energies of the 6,5 and 9,6 rhodathiaborane–ligand adducts are similar for these Lewis bases. Lewis base bonding to exo-polyhedral boron vertices results in a change of the metal coordination from pseudo-octahedral Rh(III) in 1 to pseudo-square planar Rh(I) in the adducts. The chemistry described here highlights the remarkable structural flexibility of these polyhedral boron-containing compounds, their modular architecture and their easy postsynthetic modification.
Idioma: Inglés
Año: 2016
Publicado en: Dalton Transactions 45, 20 (2016), 8622-8636
ISSN: 1477-9226

Factor impacto JCR: 4.029 (2016)
Categ. JCR: CHEMISTRY, INORGANIC & NUCLEAR rank: 7 / 46 = 0.152 (2016) - Q1 - T1
Factor impacto SCIMAGO: 1.229 - Inorganic Chemistry (Q1)

Financiación: info:eu-repo/grantAgreement/ES/MICINN-FEDER/CSD2009-00050
Financiación: info:eu-repo/grantAgreement/ES/MINECO/Consolider-Ingenio/CSD2006-0015
Financiación: info:eu-repo/grantAgreement/ES/MINECO/CTQ2009-10132
Financiación: info:eu-repo/grantAgreement/ES/MINECO/CTQ2012-32095
Tipo y forma: Article (PostPrint)

Creative Commons You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.


Exportado de SIDERAL (2020-02-21-13:49:08)

Este artículo se encuentra en las siguientes colecciones:
Articles



 Record created 2017-12-13, last modified 2020-02-21


Postprint:
 PDF
Rate this document:

Rate this document:
1
2
3
 
(Not yet reviewed)