Ring-opening metathesis polymerization has been utilized to produce polymers
60 and 61 (Scheme 11). For this, triphenylene monomers having terminal
norbornenes 57 and butadienes 59 groups were synthesized (Weck et al. 1997).
Thermal behavior of these polymers is given in Table 13. The polymers 60.2 and
61.2 with decyl chain exhibited columnar mesophases, whereas polymers 60.1 and
OR
OR
RO
OR
RO
O(CH 2 ) 12 OH
OR
OR
RO
OR
RO
O(CH 2 ) 12 O
O
OR
OR
RO
OR
RO
O(CH 2 ) 12 O
O
4
OR
OR
RO
OR
RO
O(CH 2 ) 12 O
O
x
OR
OR
RO
OR
RO
O(CH 2 ) 12 O
O
4
x
OR
OR
RO
OR
RO
O(CH 2 ) 12 O
O
4
x
O
Cl
O
4
Cl
(i)
(ii)
(iii)
(iv)
(v)
57
58
59
60
62
61
Scheme 11 Synthesis of triphenylene-based side-chain polynorbornene and polybutadiene:
(i) THF, triethylamine, reflux, 16 h; (ii) Cl 2 (PCy 3 ) 2 Ru = CPhH, CH 2 Cl 2 ; (iii) SOCl 2 , THF,
triethylamine, R.T., 16 h; (iv) Cl 2 (PCy 3 ) 2 Ru = CPhH, CH 2 Cl 2 ; (v) [Ir(COD)(Cy p )(py)]PF 6 ,
CH 2 Cl 2 , 55
C, 16 h (redrawn from Weck et al. 1997)
3 Liquid Crystalline Polymers Derived from Disc-Shaped Molecules
81