920
J. M. Kauffman
SHORT PAPER
Anal. C26H20Br2 (492.3): Calcd C, 63.44; H, 4.10; Br, 32.46. Found
C, 64.14; H, 4.15; Br, 32.43
Acknowledgement
The UV data were obtained by Farzad Kobarfard. Discussions with
Charles J. Kelley, S. Wayne Moser and Chuck Hurlbut were valua-
ble. The NMR spectrum was determined and interpreted by Walter
J. Boyko, Villanova University.
2’,3’’’’-Dimethyl-p-sexiphenyl (6)
To Mg (9.27 g, 0.381 mol) was added a portion (60 mL) of a solu-
tion of bromobenzene (59.8 g, 0.381 mol) in THF (600 mL). When
the exotherm subsided, the remainder was added rapidly at reflux,
followed by 1 h at reflux. The Grignard solution was allowed to cool
to 68 °C when the catalyst PdCl2∑dppb (0.78 g, 0.00127 mol) was
added in one portion. The mixture was boiled to extract 4,4'-dibro-
mo-3,3'''-dimethyl-p-quaterphenyl (10; 58.3 g, 0.127 mol) from a
plain extractor with a glass frit into the reaction mixture overnight.
The reactor was removed from the heating mantle, and at 60 °C ini-
tially, MeOH was added in 1 mL portions to destroy excess Grig-
nard; the 7th mL caused no exotherm. Then 6 M HCl (25 mL) was
added in portions below the reflux temperature of the reaction mix-
ture, followed by MeOH (200 mL). At 30 °C the solid was filtered,
washed with MeOH (300 mL) and dried to give 46.7 g of crude 6;
mp 255–260 °C (phase-change), 355–360 °C. This solid was ex-
tracted from a 4 cm high column of Brockmann grade I basic alumi-
na in a large Ace-Kau with 3-chlorotoluene (500 mL) for a few h.
The extract was allowed to cool to 20 °C, filtered, washed with tol-
uene (100 mL) and dried to give 44.2 g, which was recrystallized
from sulfolane (185 mL) at 230 °C, cooled only to 80 °C, filtered,
washed with propan-2-ol (500 mL), and dried to give 43.5 g (70%)
of shiny white plates, mp 259–260 °C (phase-change, Lit.17
260.3 °C), 362–365 °C (Lit.10 >320 °C). The solubility was
ª80 mg/L of toluene at 20 °C. A TLC of this solution on Analtech
Alumina GF (eluent: benzene, short- and long-wave UV) gave a
single round spot with violet fluorescence; Rf 0.90.
References
(1) Berlman, I. B.; Wirth, H. O.; Steingraber, O. J. J. Phys. Chem.
1971, 75, 318.
(2) Berlman, I. B. J. Phys. Chem. 1973, 77, 562.
(3) Fluornoy, J. M. Radiat. Phys. Chem. 1988, 32, 265; Int. J.
Radiat. Appl. Instrum. Part C, and unpublished data of 1989.
(4) Moser, S. W., Bicron, Newbury, OH, USA, private commun.,
7 Aug 98.
(5) Galda, P.; Rehahn, M. Synthesis 1996, 614.
(6) Zapka, W.; Brackmann, U., Appl. Phys. 1979, 20, 283.
(7) Wunderly, S. W.; Kauffman, J. M. Appl. Radiat. Isotopes
1990, 41, 809.
(8) Kauffman, J. M., Pilot Chemicals Div., New England Nuclear
Corp., Watertown, MA, USA, previously unpublished data.
(9) McKillop, A.; Elsom, L. F.,; Taylor, E. C. J. Am. Chem. Soc.
1968, 90, 2423.
(10) Subramaniam, G.; Gilpin, R. K. Synthesis 1992,1232.
(11) Kelley, C. J.; Ghiorghis, A.; Kauffman, J. M. J. Chem. Res. (S)
1997, 446; J. Chem. Res. (M) 1997, 2701.
(12) Kern, W.; Ebersbach, H. W.; Ziegler, I. Makromol. Chem.
1959, 29, 154.
(13) Seliskar, C. J.; Landis, D. A.; Kauffman, J. M.; Aziz, M. A.;
Steppel, R. N.; Kelley, C. J.; Qin, Y.; Ghiorghis, A. Laser
Chem. 1993, 13, 19.
(14) Kauffman, J. M.; Litak, P. T.; Novinski, J. A.; Kelley, C. J.;
Ghiorghis, A.; Qin, Y. J. Fluorescence 1995, 5, 295.
(15) Minato, A.; Tamao, K.; Hayashi, T.; Suzuki, K.; Kumada, M.
Tetrahedron Lett. 1981, 22, 5319.
(16) Kauffman, J. M.; Bjorkman, C. O. J. Chem. Ed. 1976, 53, 33.
(17) Subramaniam, G.; Gilpin, R. K. Mol. Cryst. Liq. Cryst. 1989,
166, 173.
1H NMR (CDCl3, TMS): d = 2.38 (s, 6 H, CH3), 7.35 (d, 2 H, H-
6',6'''', Jortho = 7.7 Hz), 7.34–7.48 (m, 10 H, H 2-6,2'''''-6'''''), 7.55 (dd,
2 H, H 5',6'''', Jortho = 7.7, Jmeta = 2.0 Hz), 7.58 (d, 2 H, H 3',2'''', Jmeta
= 2.0 Hz), 7.75 (br s, 8 H, H 2'',3'',5'',6'',2''',3''',5''',6''').
UV (1.33x10–5 M in toluene): lmax = 311 nm (e = 61 000).
Fluorescence Emission (corrected, 1.33x10–1 M in toluene): lmax
375 and 390 nm (equal intensity).
=
Anal. C38H30 (486.7): Calcd C, 93.79; H, 6.21. Found C, 93.43; H,
6.22.
The product of a later run had mp 264–266 °C (phase-change), 364–
368 °C. (Anal. Found. C, 94.19; H, 5.91).
Article Identifier:
1437-210X,E;1999,0,06,0918,0920,ftx,en;C05698SS.pdf
Synthesis 1999, No. 6, 918–920 ISSN 0039-7881 © Thieme Stuttgart · New York