TY - JOUR
T1 - Detection of stereochemical nonrigidity in a metal tetrahydroborate and estimation of the barrier
T2 - 1H nuclear magnetic resonance study
AU - Marks, Tobin J.
AU - Kolb, John R.
N1 - Funding Information:
The hydride resonance we obtain T m 22 f 8ps and AGc* w 5-0 f 0.6 kcal mol-l of this molecule broadens only slightly over the temperature (21 f: 2-5 kJ mol-l). This result, of admittedly limited range +25 to -121". These results indicate the fluxional accuracy, represents the first rate data on such fluxional process in (1) is becoming slow at -120". The low solu-systems. In addition, the use of paramagnetic probes in bility and great reactivity of (1) have prevented studies at dynamic n.m.r. may be of general utility. Further studies lower temperatures and in other solvent systems. are in progress. The frequency separation between bridge and terminal We thank the National Science Foundation and the hydrogens in (1)can be estimated by combining the chemical Petroleum Research Fund for support of this research.
PY - 1972
Y1 - 1972
N2 - Slowing of the dynamic interchange of bridge and terminal hydrogens in a metal tetrahydroborate has been observed for the first time in the low temperature 1H n.m.r. spectra of (C5H5) 3UBH4; at coalescence, ΔG* is ca. 5·0 ± 0·6 kcal mol-1 (21 ± 2·5 kJ mol -1).
AB - Slowing of the dynamic interchange of bridge and terminal hydrogens in a metal tetrahydroborate has been observed for the first time in the low temperature 1H n.m.r. spectra of (C5H5) 3UBH4; at coalescence, ΔG* is ca. 5·0 ± 0·6 kcal mol-1 (21 ± 2·5 kJ mol -1).
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U2 - 10.1039/C39720001019
DO - 10.1039/C39720001019
M3 - Article
AN - SCOPUS:37049121678
VL - 0
SP - 1019
EP - 1020
JO - Chemical Communications
JF - Chemical Communications
SN - 1359-7345
IS - 18
ER -