silicon, tin or germanium atom at the center of the phthalocyanine molecule.
Bridging can happen through three kinds of bonds like covalent bond, covalentcoordinate bond, or coordinate-coordinate bond. Synthetic routes for these polysiloxane spinal-based phthalocyanine polymers are shown in Scheme 6.
Scheme 5 Synthesis of phthalocyanine-based main-chain polymer: (i) ClOCCOCl; (ii) 24, 48 h,
90
C for 26.1 or pyridine and 4-dimethylaminopyridine to yield 26.2 (redrawn from Bryant et al.
1995 and Cook 1995)
N
N
R
R
R
R
Cl
N N
N
N
Si
R
R
R
R R
R
R
R
HO
OH
N N
N
N
Si
R
R
R
R R
R
R
R
F 3 CCOO
OOCCF 3
N N
N
N
Si
R
R
R
R R
R
R
R
N N
N
N
Si
R
R
R
R R
R
R
R
O
N N
N
N
Si
R
R
R
R R
R
R
R
O
N N
N
N
Si
R
R
R
R R
R
R
R
O
N N
N
N
Si
R
R
R
R R
R
R
R
O
O
Cl
(i)
(ii)
27
28
29
30
N
N
Si
R
R
R
R
(iii)
(iv)
(v)
Scheme 6 Synthesis of phthalocyanine-based polymer having metal-oxygen-metal bond as a
linker: (i) ion exchange; (ii) CF 3 COOCOCF 3 , pyridine; (iii) AgSO 3 CF 3 , TlSO 3 CF 3 ,
[Cu(CH 3 CN) 4 ]SO 3 CF 3 ; (iv) 180
C, 7 h or catalyst (FeCl 3 , ZnCl 2 , AlCl 3 , CdCl 2 , CaCl 2 , CsCl);
(v) 200
C (redrawn from Sauer and Wegner 1991; Sirlin et al. 1987, 1988a, b and Caseri et al.
1988)
3 Liquid Crystalline Polymers Derived from Disc-Shaped Molecules
71