The barrier to enantiomerization of N-Boc-2-lithiopyrrolidine: the effect of chiral and achiral diamines

by Yousaf, T. I.; Williams, R. L.; Coldham, I.; Gawley, R. E.

(-)-Sparteine and TMEDA dramatically lower both enthalpy and entropy of activation for the barrier to enantiomerization of N-Boc-2-lithiopyrrolidine in diethyl ether, whereas N,N'-diisopropylbispidine has little effect; the entropy of activation for enantiomerization is zero in the presence of TMEDA and slightly negative in the presence of sparteine; these data suggest a subtle change in mechanism of enantiomerization in the presence of TMEDA and sparteine.

Journal
Chemical Communications
Issue
1
Year
2008
Start Page
97-98
URL
https://dx.doi.org/10.1039/b714302h
ISBN/ISSN
1364-548X; 1359-7345
DOI
10.1039/b714302h