Lauer et al.
CuI (0.008 g, 15 mol %), I2 (0.038 g, 50 mol %), and a stir bar
were added. A septum was fitted to the flask, and a large needle
was inserted to vent the flask to the atmosphere. The flask was
placed in an oil bath heated to 60 °C, and the contents were
vigorously stirred. To the stirred solution, partially purified 14
(0.140 g, 0.296 mmol, dissolved in 20 mL of THF) was added
dropwise over a 20 h period via a syringe pump. The solution was
stirred an additional 8 h after the addition was complete. The
reaction mixture was concentrated by rotary evaporation at reduced
pressure on a 45 °C water bath followed by high vacuum. The crude
product was purified by flash chromatography on silica gel eluted
with 10-25% EtOAc in hexanes followed by a second column
eluted with 10-20% EtOAc in hexanes. The product was obtained
were added. A septum was fitted to the flask, and a large needle
was inserted to vent the flask to the atmosphere. The flask was
placed in an oil bath heated to 60 °C, and the contents were
vigorously stirred. To the stirred solution, partially purified 20
(0.175 g, 0.370 mmol) in THF (20 mL) was added dropwise over
20 h via a syringe pump. The solution was stirred an additional 8
h after the addition was complete. The reaction mixture was
concentrated by rotary evaporation at reduced pressure on a 45 °C
water bath followed by high vacuum. The crude product was
purified by flash chromatography on silica gel eluted with 10-
25% EtOAc in hexanes followed by a second column eluted with
10-20% EtOAc in hexanes. The product was obtained as a dark,
1
waxy solid (78 mg, 45% yield). Mp 166.8-170.0 °C (dec); H
1
as a waxy solid in 40% yield (56 mg). Mp 115.5-116.1 °C; H
NMR (CDCl3): δ 8.75 (d, J ) 4.6 Hz, 1H), 8.64 (d, J ) 4.6 Hz,
1H), 8.17 (d, J ) 7.8 Hz, 1H), 7.94 (d, J ) 7.8 Hz, 1H), 7.48 (s,
1H), 7.39 (dd, J ) 8.0 Hz, 4.8 Hz, 1H), 7.35 (dd, J ) 7.8 Hz, 4.6
Hz, 1H), 7.27 (s, 1H), 4.11 (m, 4H), 1.86 (m, 4H), 1.54 (m 4H),
1.01 (m, 6H); 13C NMR (CDCl3) δ 150.1, 150.0, 149.2, 148.5,
147.8, 141.5, 139.7, 137.2, 126.9, 122.6, 121.6, 119.7, 119.5, 119.2,
116.3, 115.4, 97.0, 9402, 91.2, 89.5, 85.1, 84.0, 81.9, 80.5, 69.2,
69.1, 31.27, 31.26, 19.31, 19.29, 14.0 (2CH3); IR (KBr) ν 2958,
2877, 2181, 1594, 1514, 1426 cm-1; ESI-HRMS calcd for
C32H26N2O2: 493.1892 [M + Na]+, found: 493.1901.
NMR (CDCl3): δ 8.67 (d, J ) 4.1 Hz, 2H), 8.19 (d, J ) 7.8 Hz,
2H), 7.42 (dd, J ) 7.8 Hz, 4.6 Hz, 2H), 7.30 (s, 2H), 4.14 (t, J )
6.4 Hz, 2H), 1.88 (m, 4H), 1.56 (m 4H), 1.03 (t, J ) 7.3 Hz, 6H).
13C NMR (CDCl3) δ 149.8, 148.5, 141.4, 139.6, 126.9, 122.7, 119.2,
116.0, 96.9, 89.4, 83.3, 80.3, 69.1, 31.3, 19.3, 14.0; IR (KBr) ν
3040, 2954, 2933, 2872, 2177, 2144,1591, 1516,1412 cm-1; ESI-
HRMS calcd for C32H26N2O2: 493.1892 [M + Na]+, found:
493.1889.
Annulene 6. In a 500 mL round-bottomed flask was placed 125
mL of THF and 125 mL of diisopropylamine, both of which had
been bubbled with air. Next, Pd(dppe)Cl2 (0.015 g, 15 mol %),
CuI (0.005 g, 15 mol %), I2 (0.022 g, 50 mol %), and a stir bar
were added. A septum was fitted to the flask, and a large needle
was inserted to vent the flask to the atmosphere. The flask was
placed in an oil bath heated to 60 °C, and the contents were
vigorously stirred. Partially purified 17 (83 mg, 0.176 mmol),
dissolved in 20 mL of THF, was added dropwise to the stirred
solution via a syringe pump over 20 h. The solution was stirred an
additional 8 h after the addition was complete. The reaction mixture
was concentrated by rotary evaporation at reduced pressure on a
45 °C water bath followed by high vacuum. The crude product
was purified by flash chromatography on silica gel eluted with 10-
25% EtOAc in hexanes followed by a second column eluted with
10-20% EtOAc in hexanes. The product was obtained as a dark,
Acknowledgment. This work was supported by awards from
the Research Corporation (K.C.R.), the National Science
Foundation (CHE-0138640 and CHE-0552292 to K.C.R.), and
Northern Kentucky University’s Center for Integrated Science
and Mathematics (K.C.R. and K.A.W.). K.A.W. acknowledges
support from the Camille and Henry Dreyfus Foundation. K.C.R.
and C.P. acknowledge support from the National Science
Foundation under Grant CHE-0211577. C.P. thanks the Donors
of the American Chemical Society Petroleum Research Fund
and the Thomas F. and Kate Miller Jeffress Memorial Trust
for partial support of this work. C.P. also acknowledges support
from the Camille and Henry Dreyfus Foundation through receipt
of a Henry Dreyfus Teacher-Scholar award. E.W. acknowl-
edges support from the Arnold and Mabel Beckman Foundation
through receipt of a Beckman Scholars award. S.M. thanks
CUR. Computational resources were provided, in part, by the
.edu) under NSF Grant CHE-0116435.
1
waxy solid (69 mg, 40% yield). Mp 187.8-188.6 °C (dec); H
NMR (CDCl3): δ 8.74 (d, J ) 4.6 Hz, 2H), 7.90 (dd, J ) 7.8 Hz,
1.4 Hz, 2H), 7.48 (s, 2H), 7.33 (dd, J ) 8.0 Hz, 4.8 Hz, 2H), 4.11
(t, J ) 6.4 Hz, 2H), 1.85 (m, 4H), 1.52 (m 4H), 1.00 (t, J ) 7.3
Hz, 6H); 13C NMR (CDCl3) δ 150.1, 149.3, 148.0, 136.8, 121.5,
119.7, 119.5, 115.8, 93.9, 91.5, 93.9, 82.0, 69.2, 31.3, 19.3, 14.0;
IR (KBr) ν 2951, 2866, 2180, 1543, 1512, 1424, 1247 cm-1; ESI-
HRMS calcd for C32H26N2O2: 471.2072 [M + H]+, found:
471.2072.
Supporting Information Available: 1H and 13C NMR spectra
for 5-7, 9, 11-13, 16, and 19. Synthesis of 9-12 and 15-20.
Absorption and emission spectra for 5-7, 13, 16, and 19. Energetics
of 5′-7′ and Cartesian coordinates for all calculated structures. This
information is available free of charge via the Internet at
Annulene 7. In a 500 mL round-bottomed flask was placed 125
mL of THF and 125 mL of diisopropylamine, both of which had
been bubbled with air. Next, Pd(dppe)Cl2 (0.032 g, 15 mol %),
CuI (0.011 g, 15 mol %), I2 (0.047 g, 50 mol %), and a stir bar
JO7019724
484 J. Org. Chem., Vol. 73, No. 2, 2008