Chemical modification of amide-based catenanes and rotaxanes II. Synthesisof tertiary amine [2]catenanes and [2] rotaxanes via N-methylation followed by borane reduction of secondary amide [2]catenanes and [2]rotaxanes and mobility of their components

Citation
N. Watanabe et al., Chemical modification of amide-based catenanes and rotaxanes II. Synthesisof tertiary amine [2]catenanes and [2] rotaxanes via N-methylation followed by borane reduction of secondary amide [2]catenanes and [2]rotaxanes and mobility of their components, B CHEM S J, 74(1), 2001, pp. 149-155
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry
Journal title
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
ISSN journal
0009-2673 → ACNP
Volume
74
Issue
1
Year of publication
2001
Pages
149 - 155
Database
ISI
SICI code
0009-2673(200101)74:1<149:CMOACA>2.0.ZU;2-V
Abstract
Secondary amide [2]catenane 1a was converted to the corresponding tertiary amide [2]catenane 1b by repetitive treatment with a methylating system of C H3I and KOH in DMSO. The amide functions of 1b were reduced with borane in refluxing THF to give the corresponding tertiary amine [2]catenane 1c. Thei r structures were characterized by NMR, IR, and FAB-MS spectroscopies. An X -ray crystallographic analysis of 1c showed that its solid-state structure was stabilized by a CH-pi interaction between the p-xylylene and m-xylylene units, together with a pi-pi stacking interaction between the two m-xylyle ne units. A variable temperature H-1 NMR study suggested that Ic had compon ents of highly enhanced mobility in CDCl3, even at lower temperature, altho ugh a much weaker interaction, such as the CH-pi. interaction, existed betw een their components in solution. Tertiary amine [2]rotaxane 3c was obtaine d from the corresponding secondary amide [2]rotaxane 3a by a procedure simi lar to that used for la. The H-1 NMR spectra indicated that the mobility of the components of 3c is sufficiently high even at lower temperature.