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 Title: Studies of alpha-lithioamine synthetic equivalents: I. Elaboration of primary amines. II. Detection of an intermediate in the lithiation of a benzylic urea Author(s): Resek, James Edward Doctoral Committee Chair(s): Beak, Peter Department / Program: Chemistry Discipline: Chemistry Degree Granting Institution: University of Illinois at Urbana-Champaign Degree: Ph.D. Genre: Dissertation Subject(s): Chemistry, Organic Abstract: Reagents for the $\alpha$-substitution of N-Boc-benzylamine and N-Boc-allylamine have been developed via dilithiation and electrophilic substitution. Discussion of the specific conditions employed to accomplish these transformations is presented, as well as mechanistic speculation. Dilithiation and substitution of O-benzyl-N-methyl carbamate has been achieved, and use of sec-BuLi/(-)sparteine as the base provided the corresponding products with up to 57% enantiomeric excess. Lithiation of N-tert-butyl-N-benzyl carbamates resulted in rearrangement to phenylglycine derivatives. These related investigations are also discussed.The intramolecular and intermolecular primary hydrogen-deuterium kinetic isotope effects for the benzylic deprotonation of N-benzyl-N,N$\sp\prime$-dimethyl urea with sec-BuLi/TMEDA have been measured to be 13 $\pm$ 3 and 2.0 $\pm$ 0.7, respectively, at $-$78$\sp\circ$C. These substantially different values exclude a one-step deprotonation mechanism and are taken as evidence for the formation of a pre-lithiation complex between the substrate and sec-BuLi which has a rate of decomplexation that is competitive with proton transfer. Detailed kinetic analysis and discussion of the implications of these results are presented. Issue Date: 1994 Type: Text Language: English URI: http://hdl.handle.net/2142/21980 Rights Information: Copyright 1994 Resek, James Edward Date Available in IDEALS: 2011-05-07 Identifier in Online Catalog: AAI9416430 OCLC Identifier: (UMI)AAI9416430
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