The chemistry of the [CX3]+ Lewis acids: classical and non-classical aspects. High resolution X-ray studies on the isoelectronic [CX3]+ and BX3 particles ( X = Cl - I)
Final Report Abstract
With this project, we established that the highly Lewis acidic CX3+ cations with X = Cl‐I are directly accessible by silver salt metathesis from silver salts of the weakly coordinating anions [Al(ORF)4]– and [(FRO)3Al–F–Al(ORF)3]− anions (RF = C(CF3)3) and CX4. Their structure and bonding was intensely established and discussed, both by experimental as well as theoretical investigations. The reactivity of especially the CI3+ ions towards weak Lewis bases was investigated. Interestingly, while the weak AX3 bases (A = P, As; X = Cl‐I) were suitable to serve as donors, classical donor solvents like OEt2 proved unsuitable and instead an ether cleavage and formation of H(OEt2)2+[Al(ORF)4]–, ethene and I3C‐OEt was observed. Thus, the also desired non‐classical adducts of CX3+ could not be realized. For the entire series of isoelectronic EX3 particles (E = B, C+; X = F‐I) we could introduce reference values for their E‐X bond distances as well as for the respective vibrational frequencies. Also the underlying thermodynamics in terms of mBE’s of the EX bonds and heats of formation was firmly established based on experimental and very high level theoretical considerations. The direct results of this very successful project were detailed in hitherto five primary publications, four of which received special attention as Hot Papers or as reaching Download Records.
Publications
- “A Computational Study of the Enthalpies of Formation ΔfH° and Mean Bond Enthalpies (mBEs) of H4‐nEXn0/‐ and H3‐nEXn+/0 (E = C, B; X = F‐I)“. J. Phys. Chem. A 2007, 111, 13207‐13217
I. Raabe, D. Himmel, I. Krossing
- “Exploring the Chemistry of free CI3+: Reactions with the weak Lewis Bases PX3 (X = Cl‐I), AsI3 and Et2O”. Dalton Trans. 2007, 5376‐5386
I. Raabe, C. Röhr, I. Krossing
- “Reference values for the B‐X bond lengths of BI3 and BBr3”. Z. Allg. Anorg. Chem. 2008, 634, 704‐707
G. Santiso Quiñones, I. Krossing
- “Stable CI3+ Salts and Attempts to Prepare CHI2+ and CH2I+”. Dalton Trans. 2008, 946‐956
I. Raabe, D. Himmel, S. Müller, N. Trapp, M. Kaupp and I. Krossing
- “CCl3+ and CBr3+ salts with the [Al(ORF)4]− and [(FRO)3Al–F–Al(ORF)3]− anions (RF = C(CF3)3”. Dalton Trans. 2011, 1448‐1452
Anna J. Lehner, Nils Trapp, Harald Scherer, Ingo Krossing
