An experimental and computational study of the enantioselective lithiation of N-Boc-pyrrolidine using sparteine-like chiral diamines

Journal of the American Chemical Society

Volumn 126, Issue 47, 2004, Pages 15480-15489

  O'Brien, Peter ^a   Wiberg, Kenneth B ^b   Bailey, William F ^c   Hermet, Jean Paul R ^a   McGrath, Matthew J ^a  

^a UNIVERSITY OF YORK   (United Kingdom)

^b YALE UNIVERSITY   (United States)

^c UNIVERSITY OF CONNECTICUT   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ACTIVATION ENERGY; AMINES; PROTONS;

ENANTIOSELECTIVITY; LITHIATION; PROTON TRANSFER;

LITHIUM;

METHYL GROUP; PYRROLIDINE DERIVATIVE; SPARTEINE;

ARTICLE; CHIRALITY; ENANTIOSELECTIVITY; ENERGY; LITHIATION; PHASE TRANSITION; PROTON TRANSPORT; THEORETICAL MODEL;

EID: 9644271552     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja046834p     Document Type: Article

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56. From an experimental point of view, the N-H diamine 8 is a "theoretical ligand", as the NH would itself be deprotonated by the alkyllithium base (and presumably diamine 8 would be used in conjunction with 2 equiv of alkyllithium, representing a significant departure from the usual experimental conditions). Amino ether 9 is, to the best of our knowledge, an unknown compound, and we have been unable to prepare diamine 10 in enantioenriched form (ref 7b). See also: Harrison, J. R.; O'Brien, P.; Porter, D. W.; Smith, N. M. J. Chem. Soc., Perkin Trans. 1 1999, 3623.