n
/cm−1 2224; 1H NMR (400 MHz, CDCl ): d 8.42 [1H
max
3
(H ), d, J
2.2], 8.31 [1H (H ), dd, J
2.0, J
9.0], 7.91
3
5−3
5
3−5
6−5
[1H (H ), d, J
9.2], 7.49 [2H (H
) d, J =J =9.0],
6
5−6
2∞,6∞
3∞2∞ 5∞6∞
7.42 [1H (H ), d, J
15.8], 7.21 [1H (H ), d, J
16], 6.69
a
b−a
b
a−b
[2H (H
) d, J
=J
=9.0], 3.10 [6H (NMe ), s];
3∞,5∞
2∞−3∞
6∞−5∞
2
13C NMR (100 MHz, CDCl ): d 151.55, 147.42, 144.62, 138.51,
3
129.42 (C
), 128.62, 127.14, 124.85, 122.88, 116.50, 116.42,
2∞,6∞
111.89 (C
), 110.30, 40.09 (NMe ).
3∞,5∞
2
This work was funded by the EPSRC through GR/H66891
(21st Century Materials initiative) and through a studentship
(to N. R. K.).
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2
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Paper 6/07980F; Received 25th November, 1996
630
J. Mater. Chem., 1997, 7(4), 625–630