ORGANIC
LETTERS
2008
Vol. 10, No. 5
773-776
Facile Synthesis of
9,10-Diarylphenanthrenes and
Poly(9,10-diarylphenanthrene)s
Bo He,† Hongkun Tian,† Yanhou Geng,*,† Fosong Wang,† and Klaus Mullen‡
1
State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of
Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese
Academy of Sciences, Changchun 130022, People’s Republic of China, and
Max-Planck-Institut fu¨r Polymerforschung, Ackermannweg 10,
D-55128 Mainz, Germany
Received November 28, 2007
ABSTRACT
+
One-pot reduction of 9,10-diaryl-9,10-dihydrophenanthrene-9,10-diols to 9,10-diarylphenanthrenes was achieved with Zn/H in acetic acid.
Accordingly, various novel phenanthrenes and polyphenanthrenes with efficient blue emission were easily synthesized.
Conjugated oligomers and polymers have been intensively
explored for their applications in electronics, photonics, and
optoelectronics in the last two decades.1 Further improvement
of the device performance such as efficiency and lifetime
relies on not only the development of new fabrication
techniques and device configurations, but also on the
incessant exploration of new materials. Research has there-
fore focused on the design and synthesis of phenylene-based
stepladder conjugated polymers, which have shown unique
and promising optoelectronic properties.2
containing PhA have been reported to date.4-6Particularly,
the synthesis of soluble polyphenanthrenes (PPhAs)6 is still
rather difficult for lack of facile methods to prepare poly-
merizable PhA derivatives carrying the necessary solublizing
groups.
PhAs with halogen atoms at the 2,7-positions and solu-
blizing groups at the 9,10-positions have so far been
synthesized in two different ways: (1) McMurry coupling
of carbonyl groups in 4,4′-dibromo-2,2′-di(4-decylbenzoyl)-
1,1′-biphenyl6a and (2) Friedel-Crafts reaction of phenan-
threnequinone (PhAQ) with phenol followed by alkoxylation.6b
However, these protocols are limited by multistep reactions
or their narrow scope. MacLachlan et al. also reported the
Phenanthrene (PhA) is one of the most stable fused
aromatics.3 Its high resonance energy qualifies it as an ideal
building block for conjugated systems with a high energy
gap. However, only a few conjugated oligomers or polymers
(3) Hepworth, J. D.; Waring, D. R.; Waring, M. J. Basic Concepts in
Chemistry: Aromatic Chemistry; John-Wiley & Sons, New York, 2003.
(4) (a) Tian, H.; Shi, J.; Dong, S.; Yan, D.; Wang, L.; Geng, Y. H.;
Wang, F. Chem. Commun. 2006, 3498-3500. (b) Tian, H.; Wang, J.; Shi,
J.; Yan, D.; Wang, L.; Geng, Y. H.; Wang, F. J. Mater. Chem. 2005, 15,
3026-3033.
(5) Boden, B. N.; Jardine, K. J.; Leung, A. C. W.; MacLachlan, M. J.
Org. Lett. 2006, 8, 1855-1858.
(6) (a) Yang, C.; Scheiber, H.; List, E. J. W.; Jacob, J.; Mu¨llen, K.
Macromolecules 2006, 39, 5213-5221. (b) Grisorio, R.; Suranna, G. P.;
Mastrorilli, P.; Nobile, C. F. Org. Lett. 2007, 9, 3149-3152.
† Changchun Institute of Applied Chemistry.
‡ Max-Planck-Institut fu¨r Polymerforschung.
(1) Semiconducting Polymers: Chemistry, Physics, and Engineering;
Hadziioannou, G., van Hutten, P. F., Eds.; Wiley-VCH: Weinheim,
Germany, 2000.
(2) (a) Scherf, U.; List, E. J. W. AdV. Mater. 2002, 14, 477-487. (b)
Setayesh, S.; Marsitzky, D.; Mu¨llen, K. Macromolecules 2000, 33, 2016-
2020. (c) Jacob, J.; Sax, S.; Piok, T.; List, E. J. W.; Grimsdale, A. C.;
Mu¨llen, K. J. Am. Chem. Soc. 2004, 126, 6987-6995.
10.1021/ol702873z CCC: $40.75
© 2008 American Chemical Society
Published on Web 01/31/2008