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3
4
7.94 (d, 2H, J¼7.0 Hz, H1), 7.70 (d, 4H, J¼1.8 Hz, Hp),
123.3, 122.4, 122.3, 121.4, 98.4, 35.1, 34.7, 32.2, 31.6. Ele-
mental analysis: calcd for C81H80I2O: C 73.52, H 6.09,
found C 73.22, H 5.98; MS (DCI/NH3, CH2Cl2) m/z 1340
(M++NH+4, 7%, calcd for C81H84I2NO: 1340.5), 1323
(M+H+, 100%, calcd for C81H81I2O: 1323.4).
4
3
7.45 (t, 2H, J¼1.8 Hz, Ho), 7.35 (d, 2H, J¼7.0 Hz, H2),
3.52 (s, 4H, ethane bridge), 1.40 (s, 36H, CH3); 13C NMR
(CDCl3) d (ppm) 202.6, 155.4, 150.7, 146.7, 143.9, 131.0,
128.1, 123.3, 122.4, 122.3, 121.4, 35.1, 32.2, 31.6. Elemen-
tal analysis: calcd for C45H49O: C 89.06, H 8.30, found C
89.00, H 8.50; MS (DCI/NH3, CH2Cl2) m/z 607.2 (MH+,
100%, calcd 607.4).
4.1.12. Diiodo compound 12a. A mixture of 11a (0.073 g,
0.055 mmol) and 1,2-di(4-tolyl)ethyne
6
(0.011 g,
0.055 mmol) was dissolved in diphenylether (3 mL) and
heated at reflux (260 ꢀC) overnight under argon. After cool-
ing, the solvent was evaporated using the Kugelrohr distilla-
tion apparatus. The dark brown solid was adsorbed on silica
and purified by column chromatography (SiO2, hexane/di-
chloromethane 0–10%) to afford 12a as a dark brown solid
4.1.9. Compound 9a. A mixture of 1,2-bis(4-tert-butylphe-
nyl)ethyne (5) (0.048 g, 0.165 mmol) and 8 (0.100 g,
0.165 mmol) was dissolved in diphenylether (3 mL) and
heated at reflux (260 ꢀC) overnight under argon. After cool-
ing, the solvent was evaporated using the Kugelrohr distilla-
tion apparatus and the red solid was purified by column
chromatography (SiO2, hexane/dichloromethane 0–10%).
Compound 9a was obtained as a yellow oil with a 97% yield.
1H NMR (CDCl3) d (ppm) 7.22 (t, 2H, 4J¼1.7 Hz), 7.19 (d,
4H, 4J¼1.7 Hz), 7.14 (d, 2H, 3J¼7.1 Hz), 7.01 (d, 2H,
3J¼7.1 Hz), 6.80 (d, 4H, 3J¼8.1 Hz), 6.69 (d, 4H,
3J¼8.1 Hz), 3.43 (s, 4H, ethane bridge), 1.21 (s, 36H, tert-
butyl), 1.11 (s, 18H, tert-butyl). Elemental analysis: calcd:
C 91.19, H 8.81, found C 91.02, H 8.72; MS (DCI/NH3,
CH2Cl2) m/z 886 (M++NH4+, 100%, calcd for C66H80N:
886.6), 868 (M+, 5%, calcd for C66H76: 868.6).
1
(23 mg, 30%). H NMR (250 MHz, CDCl3) d (ppm) 7.53
3
4
(d, 4H, J¼8.4 Hz), 7.15 (t, 2H, J¼1.8 Hz), 7.04 (d, 4H,
4J¼1.8 Hz), 6.94 (d, 4H, 3J¼8.4 Hz), 6.76 (d, 4H,
3J¼8.4 Hz), 6.65 (d, 4H, 3J¼3.1 Hz), 6.57 (d, 4H, 3J¼
3
3
8.4 Hz), 6.43 (d, 2H, J¼7.2 Hz), 6.00 (d, 2H, J¼7.2 Hz),
2.10 (s, 6H, Me), 1.14 (s, 36H, tert-butyl), 1.05 (s, 18H,
tert-butyl); 13C NMR (CDCl3) d (ppm) 150.4, 150.1,
137.8, 136.9, 135.4, 135.5, 134.8, 134.6, 131.5, 131.3,
131.1, 130.9, 129.4, 129.1, 128.7, 128.5, 127.4, 127.1,
125.5, 124.6, 123.3, 122.4, 122.3, 121.5, 98.2, 35.1, 34.7,
32.2, 31.6, 23.1; MS (DCI/NH3) m/z 1519 (M++NH4+,
100%, calcd for C96H98I2N: 1518.6), 1501 (M+H+, 7%,
calcd for C96H95I2: 1501.5).
4.1.10. Diketone 10a. Compound 9a (80 mg, 0.092 mmol)
and benzeneseleninic anhydride (33 mg, 0.092 mmol)
were placed under argon in a 50 mL flask and chlorobenzene
was added. The solution was heated at reflux for 62 h. The
solvent was evaporated and the residue was adsorbed on sil-
ica and purified by column chromatography (SiO2, hexane/
dichloromethane 0–40%). Compound 10a was obtained as
4.1.13. Wheelbarrow 13a. Compound 12a (15 mg,
0.01 mmol) and 9-ethynyltriptycene (3) (12.23 mg,
0.043 mmol) were placed under argon in a 10 mL round bot-
tomed flask. A mixture of a degassed solution of piperidine/
THF (1:1, 2 mL) was added. In a different flask a 1:2 mixture
of Pd(PPh3)4 (5.77 mg, 0.005 mmol) and copper iodide
(1.9 mg, 0.01 mmol) in degassed THF (2 mL) was prepared
under argon. The second solution was added into the first one
via cannula and the reaction was allowed to stir at room tem-
perature for 24 h. The yellow solution was then treated with
10 mL of a saturated solution of NH4Cl and the organic
phase extracted three times with 15 mL portions of
CH2Cl2. The combined organic layers were thereafter
washed with 15 mL of 1 M HCl. After the separation of
the blue aqueous phase, the organic phase was dried over
anhydrous MgSO4. The filtrate was evaporated and the oil
was chromatographed (SiO2, cyclohexane/dichloromethane
0–20%). Compound 13a was obtained as an orange solid
(10 mg, 55%). lmax (3) (CD2Cl2)/nm 450 (9450), 425
(8040), 319 (22,150), 276 (sh, 17,600), 246 (sh, 39,250),
1
an orange solid (50 mg, 60%). H NMR (CDCl3) d (ppm)
7.96 (d, 2H, J¼7.3 Hz), 7.33 (t, 2H, J¼1.8 Hz), 7.29 (s,
4
4
3
3
2H), 7.14 (d, 4H, J¼1.8 Hz), 6.88 (d, 4H, J¼8.5 Hz),
3
6.71 (d, 4H, J¼8.5 Hz), 1.23 (s, 36H, tert-butyl), 1.13 (s,
18H, tert-butyl). 13C NMR (CDCl3) d (ppm) 192.4, 155.8,
152.4, 150.3, 148.7, 146.2, 143.8, 131.0, 128.1, 127.4,
126.9, 123.3, 122.4, 122.3, 121.4, 34.7 (4 Cq-tert), 34.0 (2
Cq-tert), 31.1 (12 CMe3), 30.8 (6 CMe3). Elemental analy-
sis: calcd for C66H72O2: C 88.35, H 8.09, found C 87.98,
H 7.90; MS (DCI/NH3, CH2Cl2) m/z 897 (MH+, 8%, calcd
896.6), 914 (M+NH+4, 82%, calcd 913.6), 931 (M+2NH+4,
82%, calcd 930.6).
4.1.11. Cyclopentadienone 11a. To a solution of compound
10a (50 mg, 0.0557 mmol) and 1,3-di(4-iodophenyl)propan-
2-one 7 (25 mg, 0.05573 mmol) in dry ethanol under argon
was added 0.055 mL of a 2 M solution of KOH in dry etha-
nol. The reaction mixture was heated to reflux for 24 h under
argon. The solvent was then evaporated and the crude reac-
tion residue was adsorbed on silica and purified by column
chromatography (SiO2, hexane/dichloromethane 0–10%).
Compound 11a was obtained as a dark brown solid
1
230 (55,400); H NMR (400 MHz, CD2Cl2) d (ppm) 7.84
(m, 6H, Tript), 7.70 (d, 4H, J¼8 Hz), 7.49 (m, 6H, Tript),
3
3
7.42 (d, 4H, J¼8 Hz), 7.19 (m, 4H), 7.14 (m, 12H, Tript),
3
7.08 (m, 4H), 6.89 (d, 4H, J¼8 Hz), 6.80 (m, 6H, H9),
6.71 (d, 4H, 3J¼9 Hz), 6.40 (d, 2H, 3J¼8 Hz), 6.18 (d, 2H,
3J¼7 Hz), 5.50 (s, 2H, Tript), 2.2 (s, 6H, Me), 1.8 (s, 36H,
tert-butyl), 1.1 (s, 18H, tert-butyl); 13C NMR (100 MHz,
CD2Cl2) d (ppm) 150.1, 148.3, 148.0, 145.5, 144.7, 144.5,
140.8, 139.3, 138.2, 137.9, 137.3, 136.8, 136.7, 132.0,
131.2, 131.0, 130.4, 127.8, 126.2, 126.0, 125.6, 125.4,
125.2, 125.1, 124.9, 124.5, 123.8, 123.7, 123.5, 122.6,
122.5, 121.5, 120.0, 93.0 (alkynes), 34.8 (4 Cq-tert), 34.1
(2 Cq-tert), 31.2 (12 CMe3), 31.0 (6 CMe3), 21.0 (2 CH3);
MS (MNBA FAB) m/z 1802 (M+H+, 100%), HRMS
(FAB) m/z 1801.9500 (M+, calcd for C140H120: 1801.9468).
1
(73 mg, 100%). H NMR (250 MHz, CDCl3) d (ppm) 7.66
(d, 4H, J¼7.2 Hz), 7.50 (d, 4H, J¼8 Hz), 7.32 (t, 2H,
3
3
4J¼1.7 Hz), 7.22 (d, 4H, 4J¼1.7 Hz), 7.12 (d, 4H, 3J¼
3
3
8 Hz), 7.04 (d, 2H, J¼7.2 Hz), 6.84 (d, 4H, J¼8 Hz),
3
6.75 (d, 4H, J¼8 Hz), 1.26 (s, 36H, tert-butyl), 1.11 (s,
18H, tert-butyl); 13C NMR (CDCl3) d (ppm) 200.1, 165.1,
150.4, 150.1, 137.7, 136.9, 135.6, 135.4, 134.9, 134.6,
131.5, 131.3, 131.1, 130.7, 127.4, 127.1, 125.5, 124.4,