Synthesis, structural, spectroscopic and electrochemical studies of carborane substituted naphthyl selenides

[EN] New unsymmetrical selenides bearing an o-carborane and a naphthalene ring as the substituents were prepared by the cleavage of the corresponding diselenides. The compounds were characterized by means of spectroscopic and analytical methods. Se-77 NMR signals of the selenium atoms attached to the carbon atoms of the carborane cages are shifted downfield in comparison to those bonded only to the aromatic rings, indicating an electron withdrawing effect of the o-carboranyl substituent. Compounds 1-(2-R-1,2-dicarba-closo-carboranyl)naphthyl selenides (R = Me, 1; Ph, 2) were characterized by means of single crystal X-ray diffraction. The influence of the electronic nature of the substituents attached to the selenium atoms on the structural parameters and packing properties of naphthyl selenides are discussed. Theoretical calculations and cyclic voltammetry (CV) studies were carried out to compare the bonding nature of carboranyl and analogous aryl selenium compounds. Cyclic voltammetry studies of naphthyl carboranyl mono and diselenides have shown that the carboranyl fragment polarizes the Se lone pair making it less prone to generate a Se-Se bond.This work was supported by the Japan-Spain Research Cooperative Program, Joint Project, 2004JP0102 from Japan Society for the Promotion of Science (JSPS) and CSIC, CICYT (CTQ2010-16237) and the Generalitat de Catalunya, 2009/SGR/00279. Dr O. Guzyr is grateful to Ministerio Education, Cultura y Deporte for grant SAB2003-0122.Guzyr, O.; Viñas, C.; Wada, H.; Hayashi, S.; Nakanishi, W.; Teixidor, F.; Vaca Puga, A.... (2011). Synthesis, structural, spectroscopic and electrochemical studies of carborane substituted naphthyl selenides. Dalton Transactions. 40(13):3402-3411. https://doi.org/10.1039/c0dt01658fS34023411401

Conversion of alkyltantalum chlorides to fluorides using trimethyltin fluoride as a fluorinating agent. Crystal structures of (p-MeC<SUB>6</SUB>H<SUB>4</SUB>CH<SUB>2</SUB>)<SUB>3</SUB>TaF<SUB>2</SUB>, (Me<SUB>3</SUB>SnCl&#183;Me<SUB>3</SUB>SnF&#183;TaF<SUB>5</SUB>)<SUB>n</SUB>, (Me<SUB>3</SUB>Si)<SUB>2</SUB>CHTaCl<SUB>4</SUB>, {(Me<SUB>3</SUB>Si)<SUB>2</SUB>CHTaCl<SUB>4</SUB>&#183;[(Me<SUB>3</SUB>Si)<SUB>2</SUB>CH]<SUB>2</SUB>Ta<SUB>2</SUB>Cl<SUB>6</SUB>(&#956;<SUB>2</SUB>-O)}, and (Me<SUB>3</SUB>Si)<SUB>2</SUB>CHTaF<SUB>4</SUB>

The reactions of alkyltantalum chlorides with trimethyltin fluoride were found to be highly dependent on the number of organic ligands on tantalum as well as on the electronic and the steric nature of the substituents. The synthesis of trialkyltantalum difluorides of general formula (RCH2)3TaF2 (R = Ph, 1; R = p-Tol, 2; R = Me3Si, 3) and the first example of the alkyltantalum tetrafluoride (Me3Si)2CHTaF4 (8) are reported. The compounds (p-MeC6H4CH2)3TaF2, (Me3SnCl&#183;Me3SnF&#183;TaF5)n, (Me3Si)2CHTaCl4, {(Me3Si)2CHTaCl4&#183;[(Me3Si)2CH]2Ta2Cl6(&#956;2-O)}, and (Me3Si)2CHTaF4 respectively have been characterized by single-crystal X-ray structural analysis