The barrier to enantiomerization of N-Boc-2-lithiopyrrolidine: the effect of chiral and achiral diamines
نویسندگان
چکیده
منابع مشابه
The barrier to enantiomerization of N-Boc-2-lithiopyrrolidine: the effect of chiral and achiral diamines.
(-)-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 mechan...
متن کاملThe barrier to enantiomerization and dynamic resolution of N-Boc-2-lithiopiperidine and the effect of TMEDA.
The kinetics of enantiomerization and dynamic thermodynamic resolution (DTR) of N-Boc-2-lithiopiperidine have been measured, revealing significant differences in enthalpy and entropy for these processes and a role for the achiral ligand TMEDA; the racemization and the DTR are catalytic and first order in [TMEDA], and this has implications for asymmetric synthesis with chiral organolithiums.
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ژورنال
عنوان ژورنال: Chem. Commun.
سال: 2008
ISSN: 1359-7345,1364-548X
DOI: 10.1039/b714302h