Spectroscopic and solution properties of phenoxyphosphazene random copolymers containing optically active binaphthoxy groups

Citation
Ga. Carriedo et al., Spectroscopic and solution properties of phenoxyphosphazene random copolymers containing optically active binaphthoxy groups, MACROMOLEC, 33(10), 2000, pp. 3671-3679
Citations number
30
Categorie Soggetti
Organic Chemistry/Polymer Science
Journal title
MACROMOLECULES
ISSN journal
00249297 → ACNP
Volume
33
Issue
10
Year of publication
2000
Pages
3671 - 3679
Database
ISI
SICI code
0024-9297(20000516)33:10<3671:SASPOP>2.0.ZU;2-A
Abstract
The reaction of a mixture of [NPCl2](n) and Cs2CO3 first with (R)-(+)-1,1'- binaphthyl-2,2'-diol (HO-C10H6-C10H6-OH) (binaphthol) and subsequently with phenol (HO-C6H5) in refluxing 1,4-dioxane gave the series of the optically active random copolymers {[NP(O2C20H12)](x)[NP(OC6H5)(2)](1-x)}(n) (2). Ab solute molecular weight distributions and radius of gyration have been dete rmined by size exclusion chromatography, using simultaneously multiangle li ght scattering and differential refractive index detectors. The dependence of the dimensions of the polymers on the molecular weight through the corre sponding scaling laws is studied. In addition, a stereochemical study of ho mopolymers [NP(O2C20H12)](n), I and copolymers 2 based on the CD exciton ch irality method is also included. The reaction of the partially substituted polymer [NP(R-O2C20H12)(0.4)(Cl-2)(0.6)](n) with the stoichiometric amount of racemic binaphthol, or with a large excess of the latter, in the presenc e of Cs2CO3 gave the same polymer [NP(R-O2C20H12)(0.4)- (rac-O2C20H12)(0.4) ](n) [(-)-3] irrespective of the amount of racemic binaphthol used, showing no enantiomeric induction by the R-binaphthoxy units already present in th e polymer.