Pd-Catalyzed Cocyclotrimerization of Arynes
J . Org. Chem., Vol. 65, No. 21, 2000 6949
122.5, 119.3, 118.8 (q, J ) 321 Hz), 0.1; MS, m/z (%): 398 (23);
calcd: 366.0515, found: 366.0512. Data for 25b:27 mp: 196
°C; H NMR (CDCl3) δ 7.87 (t, J ) 9.6 Hz, 2H), 3.94 (s, 6H),
3.85 (s, 6H); MS m/z (%): 396 (19).
1
HRMS for C18H17F3O3SSi, calcd: 398.0620, found: 398.0624.
3-Tr im eth ylsilylp h en a n th r yl 4-Tr iflu or om eth a n esu l-
fon a te (21). A solution of 3-bromo-4-phenanthrol (19, 650 mg,
2.38 mmol) and HMDS (490 µL, 2.83 mmol) in THF (10 mL)
was refluxed for 90 min. The solvent was evaporated under
reduced pressure, and the residue was subjected to vacuum
to remove excess NH3 and unreacted HMDS. Following the
procedure described above for the preparation of 9, the crude
product was treated with n-BuLi (1.09 mL, 2.41 M, 2.62 mmol)
and Tf2O (500 µL, 3.0 mmol). The residue obtained after
workup was purified by column chromatography (SiO2; hex-
ane) to afford 21 as a white solid (747 mg, 79%): mp 49 °C;
1H NMR (CDCl3) δ 9.10 (m, 1H), 7.96-7.66 (m, 7H), 0.66 (s,
9H); 13C NMR (CDCl3) δ 149.5, 135.5, 134.1, 133.1, 132.4,
129.0, 128.5, 128.1, 127.9, 127.6, 127.3, 126.5, 125.5, 123.9,
118.5 (q, J ) 321 Hz), 0.5; MS, m/z (%): 398 (17); HRMS for
Cocycliza tion of 3-Meth oxy-1,2-d id eh yd r oben zen e (3-
m eth oxyben zyn e, 2). Syn th esis of Dim eth yl 1,8-Dim eth ox-
yp h en a n th r en e-9,10-d ica r boxyla te (27) a n d Dim eth yl
1,5-Dim eth oxyph en an th r en e-9,10-dicar boxylate (28). Pro-
cedure a was followed, using 26 (164 mg, 0.5 mmol), Pd(PPh3)4
(16 mg, 0.025 mmol), 23 (0.074 mL, 0.6 mmol), and CsF (152
mg, 1 mmol). Column chromatography (Al2O3; 1:3 CH2Cl2/
hexane then 1:1:2 CH2Cl2/Et2O/hexane) afforded 1,5,12- and
1,5,9-trimethoxytriphenylenes (3 mg, 6%), 27 (20 mg, 22%),
28 (53 mg, 60%), and 29 (12 mg, 6%). Syn th esis of Tetr a -
m eth yl 5-Meth oxyn a p h th a len e-1,2,3,4-tetr a ca r boxyla te
(29). Procedure a was followed, using 26 (115 mg, 0.35 mmol),
Pd2(dba)3‚CHCl3 (18 mg, 0.018 mmol), 23 (0.215 mL, 1.75
mmol), and CsF (106 mg, 0.7 mmol) in CH3CN (7 mL). Column
chromatography (SiO2; 1:1:2 CH2Cl2/Et2O/hexane) afforded 27
(2 mg, 3%), 28 (7 mg, 11%), and 29 (112 mg, 82%). Data for
C
18H17F3O3SSi, calcd: 398.0620, found: 398.0620.
Gen er a l P r oced u r es for th e Cocycliza tion of Ar yn es
1
27: mp 252 °C; H NMR (CDCl3) δ 8.27 (d, J ) 8.5 Hz, 2H),
w ith DMAD. P r oced u r e a . A solution of the aryne precursor
(0.5 mmol approximately) in CH3CN (5 mL) was added to a
suspension of finely powdered anhydrous CsF (2 equiv), DMAD
(23, 1.4 equiv), and Pd(PPh3)4 (0.1 equiv) in CH3CN (5 mL).
The mixture was stirred under argon at room temperature for
12 h. The solvent was evaporated, and the residue was
subjected to column chromatography to isolate the products.
P r oced u r e b. As for Procedure a, but using a larger excess
of 23 (5 equiv) and Pd2(dba)3‚CHCl3 (0.05 equiv) as catalyst.
7.59 (t, J ) 8.2 Hz, 2H), 7.07 (d, J ) 7.9 Hz, 2H), 3.96 (s, 12H);
13C NMR (DMSO-d6) δ 155.2, 131.2, 129.2, 125.5, 117.8, 116.2,
109.1, 56.8, 52.2; MS, m/z (%): 354 (92); HRMS for C20H18O6,
calcd.: 354.1103, found: 354.1103. Data for 28: mp 159 °C;
1H NMR (CDCl3, 0.05 M) δ 9.33 (dd, J ) 8.8, 0.7 Hz, 1H), 7.65-
7.51 (m, 3H), 7.18 (dd, J ) 7.2, 1.8 Hz, 1H), 7.08 (dd, J ) 7.5,
0.4 Hz, 1H), 4.06 (s, 3H), 4.01 (s, 3H), 3.95 (s, 3H), 3.94 (s,
3H); 13C NMR (CDCl3) δ 170.0, 168.7, 158.4, 155.2, 132.3,
129.6, 129.1, 128.2, 127.7, 127.5, 121.3, 121.0, 118.8, 118.6,
109.8, 108.3, 56.7, 55.7, 52.7, 52.3; MS, m/z (%): 354 (100);
HRMS for C20H18O6, calcd: 354.1103, found: 354.1102; Anal.
for C20H18O6, calcd: C, 67.79; H, 5.12; found: C, 67.78; H, 5.39.
Data for 29: mp 134 °C; 1H NMR (CDCl3) δ 7.61-7.59 (m,
2H), 7.02 (dd, J ) 6.1, 2.7 Hz, 1H), 4.00 (s, 3H), 3.97 (s, 3H),
3.95 (s, 3H), 3.90 (s, 3H), 3.89 (s, 3H); 13C NMR (CDCl3) δ
168.7, 167.4, 166.6, 166.5, 155.4, 133.2, 132.2, 131.4, 130.2,
127.9, 126.5, 122.0, 118.5, 108.8, 56.7, 53.1 (overlap), 52.6; MS,
m/z (%): 390 (59); HRMS for C19H18O9 calcd: 390.0951,
found: 390.0993.
Cocycliza tion of 1,2-Did eh yd r oben zen e (ben zyn e, 1a ).
Syn th esis of Dim eth yl P h en a n th r en e-9,10-d ica r boxyla te
(24a ). Procedure a was followed, using 22a (209 mg, 0.7 mmol),
Pd(PPh3)4 (81 mg, 0.07 mmol), 23 (0.120 mL, 0.98 mmol), and
CsF (213 mg, 1.4 mmol) in CH3CN (16 mL). Column chroma-
tography (Al2O3; 1:4 CH2Cl2/hexane, then 1:1:2 CH2Cl2/Et2O/
hexane) afforded triphenylene (1 mg, 2%), 24a (86 mg, 84%)
and 25a (18 mg, 7%). Syn th esis of Tetr a m eth yl Na p h th a -
len e-1,2,3,4-tetr a ca r boxyla te (25a ). Procedure b was fol-
lowed, using 22a (179 mg, 0.6 mmol), Pd2(dba)3‚CHCl3 (31 mg,
0.03 mmol), 23 (0.380 mL, 3 mmol), and CsF (182 mg, 1.2
mmol) in CH3CN (12 mL). Column chromatography (Al2O3; 1:4
CH2Cl2/hexane, then 1:1:2 CH2Cl2/Et2O/hexane) afforded 24a
(9 mg, 10%) and 25a (180 mg, 83%). Data for 24a : mp 130
°C; 1H NMR (CDCl3) δ 8.67 (d, J ) 7.9 Hz, 2 H), 8.15 (dd, J )
8.1, 1.1 Hz, 2 H), 7.71-7.64 (m, 4 H), 4.03 (s, 6 H); 13C NMR
(CDCl3) δ 168.3, 130.9, 129.8, 128.4, 127.6, 126.9, 126.8, 122.8,
52.8; MS, m/z (%): 294 (16); HRMS for C18H14O4, calcd:
294.0892, found: 294.0905; Anal. for C18H14O4, calcd: C, 73.46;
H, 4.80; found: C, 73.90; H, 5.24. Data for 25a :26 mp 147 °C;
1H NMR (CDCl3) δ 8.07 (dd, J ) 6.5, 3.3 Hz, 2H), 7.69 (dd, J
) 6.5, 3.3 Hz, 2H), 4.02 (s, 6H), 3.92 (s, 6H); 13C NMR (CDCl3)
δ 167.1, 166.6, 133.8, 129.9, 129.7, 127.4, 126.1, 53.1; MS, m/z
(%): 360 (25); HRMS for C18H16O8, calcd: 360.0845, found:
360.0804.
Cocycliza tion of 4,5-Diflu or o-1,2-d id eh yd r oben zen e
(4,5-d iflu or oben zyn e, 1b). Syn th esis of Dim eth yl 2,3,6,7-
Tetr a flu or op h en a n th r en e-9,10-d ica r boxyla te (24b). Pro-
cedure a was followed, using 22b (117 mg, 0.35 mmol),
Pd(PPh3)4 (41 mg, 0.035 mmol), 23 (0.172 mL, 1.4 mmol) and
CsF (106 mg, 0.7 mmol). Column chromatography (SiO2; 1:3
to 1:1 CH2Cl2/hexane then 1:1:2 CH2Cl2/Et2O/hexane) afforded
2,3,6,7,10,11-hexafluorotriphenylene (3 mg, 8%), phenanthrene
24b (46 mg, 64%), and naphthalene 25b (12 mg, 8%). Syn -
th esis of Tetr a m eth yl 6,7-Diflu or on a p h th a len e-1,2,3,4-
tetr a ca r boxyla te (25b). Procedure b was followed, using 22b
(100 mg, 0.3 mmol), Pd2(dba)3‚CHCl3 (16 mg, 0.015 mmol), 23
(0.184 mL, 1.5 mmol), and CsF (91 mg, 0.6 mmol) in CH3CN
(6 mL). Column chromatography (SiO2; 1:1 CH2Cl2/hexane
then 1:1:2 CH2Cl2/Et2O/hexane) afforded 24b (5 mg, 9%) and
25b (64 mg,54%). Data for 24b: mp 223 °C; 1H NMR (CDCl3)
δ 8.12 (dd, J ) 11.6, 7.5 Hz, 2H), 7.93 (dd, J ) 11.7, 8.0 Hz,
2H), 3.97 (s, 6H); MS, m/z (%): 366 (35); HRMS for C18H10O4F4,
Cocycliza tion of 1,2-Did eh yd r on a p h th a len e (1,2-n a p h -
th yn e, 3). Syn th esis of Tetr am eth yl P h en an th r en e-1,2,3,4-
tetr a ca r boxyla te (32). Procedure b was followed, using 9 (52
mg, 0.15 mmol), Pd2(dba)3‚CHCl3 (8 mg, 0.0075 mmol), 23 (92
µL, 0.75 mmol), and CsF (46 mg, 0.3 mmol) in CH3CN (3 mL).
Column chromatography (SiO2; 3:7 CH2Cl2/hexane then 1:1:3
CH2Cl2/Et2O/hexane) afforded 32 as white solid (58 mg, 94%):
mp 162 °C; 1H NMR (CDCl3) δ 8.25 (d, J ) 8.2 Hz, 1H), 7.90-
7.85 (m, 2H), 7.77 (d, J ) 9.1 Hz, 1H), 7.69-7.55 (m, 2H), 4.03
(s, 3H), 4.01 (s, 3H), 3.99 (s, 3H), 3.95 (s, 3H); 13C NMR (CDCl3)
δ 169.9, 167.6, 167.3, 166.2, 133.9, 133.3, 131.9, 131.2, 130.3,
129.5, 128.9, 128.6, 128.2, 127.2, 126.9, 125.7, 122.8, 53.24,
53.21, 53.18, 53.13; IR (film): 1729 cm-1; UV (hexane), λmax
:
268, 222, 202 nm; MS, m/z (%): 410 (71); HRMS for C22H18O8,
calcd: 410.1002, found: 410.1016. Syn th esis of Dim eth yl
Ben zo[c]ch r ysen e-13,14-d ica r b oxyla t e (33), Dim et h yl
Diben zo[c,g]p h en a n th r en e-3,4-d ica r boxyla te (34), a n d
Dim eth yl P icen e-13,14-d ica r boxyla te (35). Procedure a
was followed, using 9 (67 mg, 0.19 mmol), Pd(PPh3)4 (22 mg,
0.019 mmol), 23 (38 µL, 0.31 mmol), and CsF (59 mg, 0.38
mmol) in CH3CN (4 mL). Column chromatography (SiO2; 1:1:8
CH2Cl2/Et2O/hexane) afforded a mixture of the naphthyne
trimers (5 mg, 21%) and a mixture of cotrimers 33, 34, and
35 (26 mg, 68%, 7.2:2.6:1 ratio, as determined by 1H NMR).
Analytical samples were obtained by preparative TLC. Data
for 33: 1H NMR (CDCl3) δ 8.88 (d, J ) 9.2 Hz, 2H), 8.30 (d, J
) 8.2 Hz, 1H), 8.05-7.96 (m, 5H), 7.7-7.61 (m, 4H), 4.10 (s,
3H), 3.99 (s, 3H); MS, m/z (%): 394 (100); HRMS for C26H18O4,
calcd: 394.1205, found: 394.1202. Data for 34: 1H NMR
(CDCl3) δ 8.31 (d, J ) 8.6 Hz, 2H, H-10 and H-11), 8.12 (d, J
) 9.0 Hz, 2H, H-2 and H-5), 7.99 (d, J ) 9.1 Hz, 2H, H-1 and
H-6), 7.95 (d, J ) 8.6 Hz, 2H, H-7 and H-14), 7.55 (t, J ) 7.3
Hz, 2H, H-8 and H-13), 7.25 (d, J ) 7.6 Hz, 2H, H-9 and H-11),
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