Configurational and conformational effects on tin-lithium exchange in alpha-aminoorganostannanes by rapid-injection NMR

by Klein, R.; Gawley, R. E.

The kinetics of tin-lithium exchange in heterocyclic alpha-aminoorganostannanes have been studied using Sn-119 rapid-injection NMR. By comparison of the observed relative rate constants, the effects of ring size, configuration, and conformation can be discerned. Stannylpyrrolidines transmetalate extremely rapidly, whereas the rate of transmetalation of stannylpiperidines varies from negligible transmetalation to rapid transmetalation. The evidence suggests that only one conformation of N-methyl-2-(tributylstannyl)piperidine transmetalates. N-Boc stannyl piperidines transmetalate at rates that vary somewhat, due in part to conformational effects.

Journal
Journal of the American Chemical Society
Volume
129
Issue
14
Year
2007
Start Page
4126-4127
URL
https://dx.doi.org/10.1021/ja0692377
ISBN/ISSN
1520-5126; 0002-7863
DOI
10.1021/ja0692377