Metathesis Polymerization of Phenylacetylene by Tungsten Aryloxo Complexes

[img]PDF - Authorized users only
Language: English
78Kb
Title:Metathesis Polymerization of Phenylacetylene by Tungsten Aryloxo Complexes
Creators:
Balcar, Hynek
Sedláček, Jan
Pacovská, Marta
Blechta, Vratislav
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 60, 3, pp. 489-497

Abstract

<p>Catalytic activity of the tungsten aryloxo complexes WCl<sub>5</sub>(OAr) and WOCl<sub>3</sub>(OAr), where Ar = 4-<i>t</i>-C<sub>4</sub>H<sub>9</sub>C<sub>6</sub>H<sub>4</sub>, 2,6-(<i>t</i>-C<sub>4</sub>H<sub>9</sub>)<sub>2</sub>C<sub>6</sub>H<sub>3</sub>, 2,6-Cl<sub>2</sub>C<sub>6</sub>H<sub>3</sub>, 2,4,6-Cl<sub>3</sub>C<sub>6</sub>H<sub>2</sub>, and 2,4,6-Br<sub>3</sub>C<sub>6</sub>H<sub>2</sub> in polymerization of phenylacetylene (20 °C, monomer to catalyst molar ratio = 1 000) was studied. The activity of WCl<sub>5</sub>(OAr) as unicomponent catalysts increases with increasing electron withdrawing character of the -OAr ligand. Addition of two equivalents of organotin cocatalysts (Me<sub>4</sub>Sn, Bu<sub>4</sub>Sn, Ph<sub>4</sub>Sn, Bu<sub>3</sub>SnH) to WCl<sub>5</sub>(O-C<sub>6</sub>H<sub>2</sub>Cl<sub>3</sub>-2,4 ,6) has only slight positive effect (slightly higher polymer yield and/or molecular weight of poly(phenylacetylene)s was achieved). However, in the case of WOCl<sub>3</sub>(O-C<sub>6</sub>H<sub>3</sub>Cl<sub>2</sub>-2, 6) catalyst, it enhances the activity considerably by eliminating the induction period. Poly(phenylacetylene)s prepared with the catalysts studied have weight-average molecular weight ranging from 100 000 to 200 000. They are <i>trans</i>-prevailing and have relatively low molar fraction of monomer units comprised in cyclohexadiene sequences (about 6%).

Title:Metathesis Polymerization of Phenylacetylene by Tungsten Aryloxo Complexes
Creators:
Balcar, Hynek
Sedláček, Jan
Pacovská, Marta
Blechta, Vratislav
Divisions:Life and Chemical Sciences > Institute of Organic Chemistry and Biochemistry > Collection of Czechoslovak Chemical Communications
Journal or Publication Title:Collection of Czechoslovak Chemical Communications
Volume:60
Number:3
Page Range:pp. 489-497
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc19950489UNSPECIFIED
ID Code:735
Item Type:Article
Deposited On:06 Feb 2009 17:03
Last Modified:06 Feb 2009 16:03

Citation

Balcar, Hynek; Sedláček, Jan; Pacovská, Marta; Blechta, Vratislav (1995) Metathesis Polymerization of Phenylacetylene by Tungsten Aryloxo Complexes. Collection of Czechoslovak Chemical Communications, 60 (3). pp. 489-497. ISSN 0010-0765

Repository Staff Only: item control page