Synthetic and Mechanistic Studies of Carbamate-Directed Lithiation Reactions: (1) Assymetric Deprotonation of N-Boc Indolines. (2) the Relationship Between Reactivity and Directing Group Orientation

A series of tin-lithium exchange experiments indicate that rotationally restricted α-lithio carbamates have increased configurational stability relative to more flexible analogs. An increase in the rate of epimerization of α-lithio carbamates in the presence of N, N, N\sp\prime , N\sp\prime-tetramethylethy lenediamine suggests that the rate-determining step for epimerization is the separation of the carbanionic carbon and the lithium. Chelation of the carbamate carbonyl oxygen to the lithium in α-lithio carbamates appears to influence their thermodynamic stability. These studies demonstrate that the position of the carbonyl group with respect to the proton removed in a carbamate-directed lithiation affects the efficiency of the reaction as well as the configurational stability of the organolithium intermediate.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemistry

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Gross, Kathleen Bertini

Contributors dc:contributor

• Beak, Peter

• Chemistry, Organic

Language dc:language

eng

Identifier

(MiAaPQ)AAI9812602

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/84378