@article{KleinpeterKoch2021,
  author    = {Kleinpeter, Erich and Koch, Andreas},
  title     = {Intramolecular carbene stabilization via 3c,2e bonding on basis of the magnetic criterion},
  series = {Tetrahedron : the international journal for the rapid publication of full original research papers and critical reviews in organic chemistry},
  volume    = {95},
  journal   = {Tetrahedron : the international journal for the rapid publication of full original research papers and critical reviews in organic chemistry},
  publisher = {Elsevier Science},
  address   = {Amsterdam},
  issn      = {0040-4020},
  doi       = {10.1016/j.tet.2021.132357},
  pages     = {9},
  year      = {2021},
  abstract  = {The spatial magnetic properties, through-space NMR shieldings (TSNMRS), of bent cyclobutylcarbene 8, 1,2-diboretane-3-ylidene 9, and some carbene analogues of boron 14-18 as most intriguing examples of carbenes, which can be stabilized as homoaromatic systems with 3c,2e bonding, have been calculated using the GIAO perturbation method employing the nucleus independent chemical shift (NICS) concept and the results visualized as iso-chemical-shielding surfaces (ICSS) of various size and direction. The TSNMRS values (actually, ring current effect/anisotropy effects as measurable in H-1 NMR spectroscopy) are employed to qualify and quantify the degree of present 3c,2e-homoaromaticity. Results are confirmed by geometry (bond angles and bond lengths) and spectroscopic data, the delta(B-11)/ppm data and the C-13 chemical shifts of the carbene electron-deficient centre.},
  language  = {en}
}
@article{KleinpeterKoch2021,
  author    = {Kleinpeter, Erich and Koch, Andreas},
  title     = {Quantification of sigma-acceptor and pi-donor stabilization in O, S and Hal analogues of N-heterocyclic carbenes (NHCs) on the magnetic criterion},
  series = {The journal of physical chemistry : A, Molecules, spectroscopy, kinetics, environment \& general theory},
  volume    = {125},
  journal   = {The journal of physical chemistry : A, Molecules, spectroscopy, kinetics, environment \& general theory},
  number    = {33},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {1089-5639},
  doi       = {10.1021/acs.jpca.1c05257},
  pages     = {7235 -- 7245},
  year      = {2021},
  abstract  = {The spatial magnetic properties, through-space NMR shieldings (TSNMRSs), of stable O, S and Hal analogues of N-heterocyclic carbenes (NHCs) have been calculated using the GIAO perturbation method employing the nucleus-independent chemical shift (NICS) concept and the results visualized as iso-chemical-shielding surfaces (ICSSs) of various sizes and directions. The TSNMRS values (actually the anisotropy effects measurable in H-1 NMR spectroscopy) are employed to qualify and quantify the position of the present mesomeric equilibria (carbenes <-> ylides). The results are confirmed by geometry (bond angles and bond lengths), IR spectra, UV spectra, and C-13 chemical shifts of the electron-deficient carbon centers.},
  language  = {en}
}
@article{KleinpeterKoch2021,
  author    = {Kleinpeter, Erich and Koch, Andreas},
  title     = {Dative or coordinative carbon-boron bond in boron trapped N-heterocyclic carbenes (NHCs)?},
  series = {Tetrahedron : the international journal for the rapid publication of full original research papers and critical reviews in organic chemistry},
  volume    = {80},
  journal   = {Tetrahedron : the international journal for the rapid publication of full original research papers and critical reviews in organic chemistry},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0040-4020},
  doi       = {10.1016/j.tet.2020.131787},
  pages     = {8},
  year      = {2021},
  abstract  = {The spatial magnetic properties, through-space NMR shieldings (TSNMRS), of isolated as well as B-C bond length varied model compounds (BR3 trapped NHCs) have been calculated using the GIAO perturbation method employing the nucleus independent chemical shift (NICS) concept and the results visualized as iso-chemical-shielding surfaces (ICSS) of various size and direction. The TSNMRS values (actually the anisotropy effects measurable in H-1 NMR spectroscopy) are employed to qualify and quantify the present dative vs. coordinative bond character of the boron-carbon bond in the trapped NHCs. Results are confirmed by bond lengths and B-11/C-13 chemical shift variations in the BR3 trapped NHCs.},
  language  = {en}
}
@article{KleinpeterHeydenreichShainyan2021,
  author    = {Kleinpeter, Erich and Heydenreich, Matthias and Shainyan, Bagrat A.},
  title     = {At the experimental limit of the NMR conformational analysis},
  series = {Organic letters},
  volume    = {23},
  journal   = {Organic letters},
  number    = {2},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {1523-7060},
  doi       = {10.1021/acs.orglett.0c03878},
  pages     = {405 -- 409},
  year      = {2021},
  abstract  = {The low temperature (95 K) NMR study of 1-Ph-1-t-Bu-silacyclohexane (1) showed the conformational equilibrium to be extremely one-sided toward thePh(ax),t-Bueq conformer. The barrier to interconversion has been measured (4.2-4.6 kcal/mol) and the conformational equilibrium [Delta nu = 1990.64 ppm (Si-29), 618.9 ppm (C-13), 1-Ph-ax:1-Pheq = (95.6-96.6\%):(3.4-4.4\%), K = 25 +/- 3, Delta G degrees = -RT ln K = 0.58-0.63 kcal/mol] analyzed. The assignment and quantification of the NMR signals is supported by MP2 and DFT calculations.},
  language  = {en}
}