The directed ortho-lithiation of lithium phenylsulfide and lithium phenylselenide plus sigma-aromaticity and the hexakis(phenylseleno)benzene dication

The directed ortho-lithiation of lithium phenylselenide by reaction with $n$-butyllithium in cyclohexane with $N$,$N$,$N\sp\prime$,$N\sp\prime$-tetramethylethylenediamine gives almost quantitative conversion to lithium 2-lithiobenzeneselenolate and is estimated to be seven to eight times faster than the directed ortho-lithiation of lithium phenylsulfide to form lithium 2-lithiobenzenethiolate. Treatment of the lithium 2-lithiobenzeneselenolate with a variety of electrophiles (D$\sb2$O, carbon dioxide, selenium, methylene chloride, methyl iodide, thioxanthone, and dimethylcarbonate) form ortho-substituted products. The treatment of dilithium benzene-1,2-diselenolate with methylene chloride and 1,2-dibromoethane forms 1,3-benzodiselenole (70.4% yield) and dihydro-1,4-benzodiselenin (54.6% yield), respectively. The ortho-lithiation and $o,o\sp\prime$-dilithiation of dilithium benzene-1,2-diselenolate is presented. The adduct to thioxanthone is ring-closed to form the (1) benzoselenopyrano (2,3,4-kl) thioxanthylium cation and 13b$H$- (1) benzoselenopyrano (2,3,4-kl) thioxanthen-13b-ol (13.3% yield).

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

2011

Author dc:creator

• Loop, Cynthia Kay

Contributors dc:contributor

• Martin, J.C.

• Chemistry, Organic

Statement dc:rights

• Copyright 1990 Loop, Cynthia Kay

Language dc:language

eng

Identifier

AAI9026257
(UMI)AAI9026257

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/21941