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Beak, Peter Resek, James Edward 2011-05-07T13:25:08Z 2011-05-07T13:25:08Z 10000-01-01 1994 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. Made available in DSpace on 2011-05-07T13:25:08Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9416430.pdf: 4886789 bytes, checksum: ab961675ae5b759359ccc9e794c45fce (MD5) Previous issue date: 1994 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:54:31Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:25:20-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9416430 (UMI)AAI9416430 http://hdl.handle.net/2142/21980 eng Copyright 1994 Resek, James Edward Chemistry, Organic Studies of alpha-lithioamine synthetic equivalents: I. Elaboration of primary amines. II. Detection of an intermediate in the lithiation of a benzylic urea text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.