Synthesis of 4,5-Diarylphenanthrenes
J . Org. Chem., Vol. 66, No. 23, 2001 7809
δ 7.61 (4 H, s), 7.56-7.52 (2 H, m), 7.49-7.45 (2 H, m), 7.33-
7.22 (4 H, m), 7.18 (4 H, s), 6.95 (2 H, s), 2.38 (2 H, s), 2.28 (12
H, s), 1.06 (18 H, s); 13C δ 141.0, 137.8, 132.17, 132.12, 130.4,
129.4, 128.0, 127.8, 126.5, 125.9, 125.1, 122.6, 96.1, 93.6, 87.6,
84.6, 79.4, 39.7, 25.6, 21.1.
33.4; MS m/z 618 (M+), 561; HRMS calcd for C48H42 (M+)
618.3287, found 618.3296. Recrystallization of 8a from CH2-
Cl2/hexanes produced a crystal suitable for the X-ray structure
analysis.
4,5-Dia r ylp h en a n th r en e 8b a n d 1H-Cyclobu t[a ]in d en e
17b. The same procedure was repeated as described for 8a
except that 0.153 g of 7b (0.198 mmol) was treated with a
mixture of 0.48 mL of a 1.0 M solution of potassium tert-
butoxide (0.48 mmol) in THF and 0.5 mL of 2-methyl-2-
propanol in 10 mL of anhydrous toluene under reflux for 10 h
to afford 0.070 g of 8b (0.091 mmol, 46% yield) as a yellow
solid and 0.014 g of 17b (0.018 mmol, 9% yield) as an orange
solid. 8b: mp 249-251 °C; IR 1486, 696 cm-1; 1H δ 7.92 (2 H,
s), 7.70 (4 H, d, J ) 7.3 Hz), 7.51-7.35 (12 H, m), 7.09 (2 H,
t, J ) 7.0 Hz), 6.78 (2 H, t, J ) 7.8 Hz), 6.72 (4 H, d, J ) 8.5
Hz), 6.42 (2 H, t, J ) 7.9 Hz), 4.44 (2 H, d, J ) 21.0 Hz), 4.20
(2 H, d, J ) 21.0 Hz), 1.87 (18 H, s); 13C δ 144.2, 141.1, 140.9,
139.7, 139.5, 139.0, 138.2, 137.2, 134.7, 132.2 (br), 131.9, 131.5,
128.7, 127.1, 126.9, 126.8, 126.1, 125.3, 123.7, 123.1, 122.0,
39.9, 37.8, 33.4; MS m/z 770 (M+), 714, 659; HRMS calcd for
Tetr a a cetylen ic Hyd r oca r bon 7a . The following proce-
dure is representative for the preparation of the tetraacetylenic
hydrocarbons 7. To a mixture of 0.310 g of 6a (0.476 mmol)
and 0.168 g of triethylsilane (1.42 mmol) in 10 mL of meth-
ylene chloride was added 0.29 mL of trifluoroacetic acid (0.433
g, 3.80 mmol). After 5 min of stirring at room temperature,
0.202 g of sodium carbonate (1.90 mmol) was added followed
by 10 mL of water and 50 mL of diethyl ether. The organic
layer was separated, washed with brine and water, dried over
sodium sulfate, and concentrated. Flash column chromatog-
raphy (silica gel/5% diethyl ether in hexanes, Rf ) 0.49)
provided 0.274 g of 7a (0.443 mmol, 93% yield, 1:1 mixture of
1
diastereomers) as a yellow solid: IR 2216, 755 cm-1; H (1:1
mixture) δ 7.57-7.40 (8 H, m), 7.32-7.22 (14 H, m), 3.64 and
3.62 (2 H, two singlets, 1:1 ratio), 1.00 (18 H, s); 13C (1:1
mixture) δ 137.4, 137.3, 132.12, 132.05, 131.6, 128.9, 128.2,
127.8, 127.3, 126.33, 126.30, 125.58, 125.51, 123.25, 123.18,
95.76, 95.70, 92.82, 92.76, 88.66, 88.60, 82.44, 82.41, 50.2,
35.45, 35.41, 27.8; MS m/z 618 (M+), 561, 505.
C
60H50 (M+) 770.3913, found 770.3925. 17b: mp 269-272 °C;
1
IR 1487, 696 cm-1; H δ 8.51 (1 H, d, J ) 9.3 Hz), 7.97 (1 H,
dd, J ) 7.9, 2.0 Hz), 7.91 (1 H, d, J ) 2.2 Hz), 7.83-7.76 (4 H,
m), 7.72 (1 H, dd, J ) 7.9, 1.8 Hz), 7.67 (1 H, dd, J ) 9.3, 2.2
Hz), 7.66 (1 H, d, J ) 7.1 Hz), 7.53-7.44 (7 H, m), 7.41-7.22
(8 H, m), 7.17 (1 H, td, J ) 7.5, 1 Hz), 7.07 (1 H, td, J ) 7.3,
1.4 Hz), 6.94 (1 H, t, J ) 7.3 Hz), 6.19 (1 H, s), 4.47 (2 H, s),
1.87 (9 H, s), 1.12 (9 H, s); spin decoupling indicates that the
signal at δ 8.51 is coupled to the signal at δ 7.67, which is
also coupled to the signal at δ 7.91; 13C δ 154.0, 152.3, 150.7,
148.0, 144.2, 141.2, 140.7, 140.5, 140.3, 139.9, 139.8, 139.1,
138.3, 138.2, 137.2, 134.0, 133.7, 132.7, 130.8, 130.6, 129.8,
129.6, 129.1, 128.9, 128.8, 127.8, 127.5, 127.4, 127.2, 127.0,
126.9, 126.8, 126.2, 125.8, 123.9, 123.6, 123.5, 121.5, 111.4,
75.7, 40.1, 38.8, 37.2, 34.3, 28.5; MS m/z 771 (MH+), 770, 713;
HRMS calcd for C60H51 (MH+) 771.3991, found 771.3987.
Tetr a a cetylen ic Hyd r oca r bon 7b. The same procedure
was repeated as described for 7a except that 0.160 g of 6b
(0.20 mmol) was treated with 0.070 g of triethylsilane (0.60
mmol) and 0.12 mL of trifluoroacetic acid (1.6 mmol) in 40 mL
of methylene chloride to afford 0.153 g of 7b (0.198 mmol, 99%
yield, 1:1 mixture of diastereomers) as a yellow solid: IR 2217,
1
761 cm-1; H (1:1 mixture) δ 7.59-7.52 (12 H, m), 7.48-7.40
(6 H, m), 7.38-7.31 (8 H, m), 7.29-7.22 (4 H, m), 3.67 and
3.63 (2 H, two singlets, 1:1 ratio), 1.03 and 1.02 (18 H, two
singlets, 1:1 ratio); 13C (1:1 mixture) δ 140.8, 140.3, 140.2,
137.5, 137.4, 132.2, 132.13, 132.10, 129.0, 128.8, 128.7, 127.8,
127.53, 127.48, 127.3, 127.0, 126.9, 126.8, 126.3, 125.65,
125.59, 122.2, 122.1, 95.8, 92.7, 89.3, 82.6, 82.4, 50.3, 35.5, 27.8;
MS m/z 770 (M+), 713, 657; HRMS calcd for C60H50 (M+)
770.3913, found 770.3899.
4,5-Dia r ylp h en a n th r en e 8c a n d 1H-Cyclobu t[a ]in d en e
17c. The same procedure was repeated as described for 8a
except that 0.270 g of 7c (0.40 mmol) was treated with a
mixture of 0.96 mL of a 1.0 M solution of potassium tert-
butoxide (0.96 mmol) in THF and 0.5 mL of 2-methyl-2-
propanol in 15 mL of anhydrous toluene under reflux for 10 h
to afford 0.108 g of 8c (0.16 mmol, 40% yield) as a yellow solid
and 0.033 g of 17c (0.049 mmol, 12% yield) as an orange solid.
Tetr a a cetylen ic Hyd r oca r bon 7c. The same procedure
was repeated as described for 7a except that 0.442 g of 6c
(0.626 mmol) was treated with 0.160 g of triethylsilane (1.38
mmol) and 0.39 mL of trifluoroacetic acid (5.0 mmol) in 10 mL
of methylene chloride to afford 0.404 g of 7c (0.599 mmol, 96%
yield, 1:1 mixture of diastereomers) as a yellow solid: IR 2214,
848 cm-1; 1H (1:1 mixture) δ 7.56-7.49 (2 H, m), 7.47-7.39 (2
H, m), 7.30-7.21 (8 H, m), 7.18-7.14 (4 H, m), 6.94 and 6.90
(2 H, two singlets, 1:1 ratio), 3.65 and 3.63 (2 H, two singlets,
1:1 ratio), 2.28 and 2.25 (12 H, two singlets, 1:1 ratio), 1.02
(18 H, s); 13C (1:1 mixture) δ 137.7, 137.4, 137.3, 132.2, 132.1,
130.2, 129.4, 128.9, 127.7, 127.3, 126.31, 126.24, 125.75,
125.71, 122.9, 95.6, 93.2, 88.0, 82.5, 50.3, 35.5, 29.2, 27.8, 21.1;
MS m/z 674 (M+), 617, 561.
8c: mp 265-270 °C; IR 1462, 707 cm-1 1H δ 7.81 (2 H, s),
;
7.44 (2 H, d, J ) 7.3 Hz), 7.10 (2 H, t, J ) 7.2 Hz), 6.84 (2 H,
d, J ) 7.9 Hz), 6.81 (2 H, s), 6.49 (2 H, d, J ) 7.9 Hz), 6.27 (4
H, s), 4.41 (2 H, d, J ) 21.0 Hz), 4.20 (2 H, d, J ) 21.0 Hz),
2.10 (12 H, s), 1.84 (18 H, s); 13C δ 144.2, 141.4, 139.1, 139.0,
138.2, 136.6, 136.2, 135.5, 132.4, 131.7, 130.2 (br), 128.0, 125.9,
125.4, 123.6, 122.9, 121.8, 39.7, 37.7, 33.3, 21.3; MS m/z 674
(M+), 617, 561; HRMS calcd for C52H50 (M+) 674.3913, found
674.3935. 17c: mp 212-215 °C; IR 1595, 1435 cm-1; 1H δ 8.40
(1 H, d, J ) 9.3 Hz), 7.67 (1 H, d, J ) 2.2 Hz), 7.64-7.57 (2 H,
m), 7.54 (2 H, s), 7.46 (1 H, d, J ) 7.5 Hz), 7.36-7.15 (4 H, m),
7.10-7.03 (2 H, m), 6.99 (1 H, t, J ) 7.5 Hz), 6.92 (2 H, d, J )
6.5 Hz), 6.48 (1 H, d, J ) 7.7 Hz), 5.88 (1 H, s), 4.46 (2 H, s),
2.43 (3 H, s), 2.41 (6 H, s), 2.31 (3 H, s), 1.85 (9 H, s), 1.14 (9
H, s); 13C δ 154.8, 152.4, 151.3, 147.7, 144.1, 140.5, 140.2, 139.5,
138.6, 138.3, 138.1, 137.6, 137.0, 135.3, 134.1, 133.5, 131.0,
129.7, 129.2, 128.8, 128.6, 127.8, 127.7, 127.1, 126.7, 126.6,
126.1, 124.7, 123.8, 123.3, 121.4, 111.0, 75.3, 40.1, 38.7, 36.9,
34.3, 28.6, 21.6, 21.44, 21.36; MS m/z 675 (MH+), 674, 617,
560; HRMS calcd for C52H50 (M+) 674.3913, found 674.3922.
4,5-Dia r ylp h en a n th r en e 8a . The following procedure is
representative for the synthesis of the 4,5-diarylphenanthrenes
8. To 0.191 g of 7a (0.309 mmol) in 10 mL of anhydrous toluene
under a nitrogen atmosphere were added 0.65 mL of a 1.0 M
solution of potassium tert-butoxide (0.65 mmol) in THF and
0.5 mL of 2-methyl-2-propanol. The reaction mixture was then
heated under reflux for 3 h. After the reaction mixture was
allowed to cool to room temperature, 10 mL of water and 50
mL of methylene chloride were introduced, and the organic
layer was separated, dried over sodium sulfate, and concen-
trated. Flash column chromatography (silica gel/10% methyl-
ene chloride in hexanes, Rf ) 0.73) provided 0.084 g of 8a
(0.136 mmol, 44% yield) as a yellow solid: mp >340 °C; IR
Ack n ow led gm en t. The financial support of the
National Science Foundation (CHE-9618676) to K.K.W.
is gratefully acknowledged. J .L.P. acknowledges the
support (CHE-9120098) provided by the Chemical In-
strumentation Program of the National Science Foun-
dation for the acquisition of a Siemens P4 X-ray
diffractometer in the Department of Chemistry at West
Virginia University.
1
1464, 705 cm-1; H δ 7.83 (2 H, s), 7.39 (2 H, d, J ) 7.3 Hz),
7.15 (2 H, t, J ) 7.4 Hz), 7.05 (2 H, t, J ) 7.3 Hz), 7.00 (4 H,
t, J ) 7.3 Hz), 6.74 (2 H, t, J ) 7.5 Hz), 6.52 (4 H, d, J ) 7.1
Hz), 6.20 (2 H, d, J ) 8.1 Hz), 4.39 (2 H, d, J ) 21.0 Hz),
4.15 (2 H, d, J ) 21.0 Hz), 1.82 (18 H, s); 13C δ 144.2,
141.2, 139.43, 139.36, 139.0, 137.1, 135.3, 132.5 (br), 131.9,
131.7, 128.1, 126.5, 126.0, 125.3, 123.6, 123.0, 122.0, 39.8, 37.8,