%0 Journal Article
%A Krow, Grant R.
%A Herzon, Seth B.
%A Lin, Guoliang
%A Qiu, Feng
%A Sonnet, Philip E.
%D 2002
%T Complex-Induced Proximity Effects.
Temperature-Dependent Regiochemical
Diversity in Lithiation−Electrophilic
Substitution Reactions of
N-BOC-2-Azabicyclo[2.1.1]hexane.
2,4- and 3,5-Methanoprolines
%U https://acs.figshare.com/articles/journal_contribution/Complex-Induced_Proximity_Effects_Temperature-Dependent_Regiochemical_Diversity_in_Lithiation_Electrophilic_Substitution_Reactions_of_i_N_i_-BOC-2-Azabicyclo_2_1_1_hexane_2_4-_and_3_5-Methanoprolines/3743784
%R 10.1021/ol026509b.s001
%2 https://acs.figshare.com/ndownloader/files/5837148
%K regioisomeric methylene
%K mixture
%K DMF
%K aldehyde 8 c
%K bridgehead acids 6
%K bridgehead acid 8
%K anion
%K quenching
%K BOC methyl ester 6 b
%X Azabicycle 4 and sec-butyllithium/TMEDA afford the C1 bridgehead α-lithio anion at 0 °C. Anion quenching with carbon dioxide, methyl
chloroformate, or DMF provide the bridgehead acid 8a (N-BOC-2,4-methanoproline), ester 8b, or aldehyde 8c, respectively. By contrast, at −78
°C these same reagents give a mixture of regioisomeric methylene and bridgehead anions whose quenching leads to mixtures of regioisomeric
methylene and bridgehead acids 6a/8a, esters 6b/8b, or aldehydes 6c/8c, respectively. The previously unknown 3,5-methanoproline was prepared
as its N-BOC methyl ester 6b.
%I ACS Publications