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4.1.2. 4-(Diethyltriazenyl)-1-iodobenzene (2). To an oven-
dried vessel containing boron trifluoride etherate (3.81 mL,
30 mmol) at K15 8C was added 4-iodoaniline (3.29 g,
15 mmol) in dichloromethane (40 mL) followed by tert-
butyl nitrite (3.60 mL, 30 mmol) in dichloromethane
(5 mL). The mixture was stirred at K15 8C for 30 min,
and then warmed to 0 8C for 30 min. Diethylamine
(12.35 mL, 120 mmol) and potassium carbonate (13.82 g,
100 mmol) were sequentially added. The reaction was
stirred at 0 8C for 2 h. The reaction mixture was then poured
into water and the aqueous layer was extracted three times
with ethyl acetate. After drying the combined organic layers
over magnesium sulfate, the solvent was removed in
vacuum to afford a crude product, which was then purified
by flash chromatography on neutral alumina (9:1; hexane/
dichloromethane) to afford 4.72 g (99%) of 1 as a light
4.1.5. Terminal alkynyl dimer (5). See procedure B.
Compound 4 (0.54 g, 1.24 mmol), methanol (10 mL),
dichloromethane (5 mL) and potassium carbonate (0.82 g,
5.0 mmol) afforded 0.45 g (100%) of 5 as a yellow liquid.
1H NMR (400 MHz, CDCl3) d 7.45 (d, JZ8.4 Hz, 2H), 7.39
(t, JZ8.4 Hz, 2H), 6.99 (s, 1H), 3.79 (q, JZ7.2 Hz, 4H),
3.46 (s, 1H), 2.67 (t, JZ7.6 Hz, 2H), 1.59 (quint, JZ7.6 Hz,
2H), 1.35 (d, JZ8.4 Hz, 2H), 1.28 (br s, 6H), 0.94 (t, JZ
7.2 Hz, 3H).
4.1.6. Iodide dimer (6). See procedure C. Compound 4
(0.48 g, 1.10 mmol) and iodomethane (5 mL) for 24 h
1
afforded 0.51 g (99%) of 6 as a yellow liquid. H NMR
(600 MHz, CDCl3) d 7.68 (d, JZ8.4 Hz, 2H), 7.21 (d, JZ
8.4 Hz, 2H), 7.01 (s, 1H), 2.65 (t, JZ7.6 Hz, 2H), 1.59
(quint, JZ7.6 Hz, 2H), 1.36 (sext, JZ7.4 Hz, 2H), 0.95 (t,
JZ7.2 Hz, 3H), 0.26 (s, 9H). 13C NMR (CDCl3, 150 MHz)
d 148.65, 137.57, 137.43, 132.99, 132.84, 130.23, 122.47,
122.21, 120.28, 102.33, 96.79, 94.52, 92.58, 84.12, 32.05,
29.11, 22.19, 13.93. LDI-MS (m/z): 462 (MC), 336 (MKI).
Anal. Calcd for C21H23ISSi: H, 5.02; C, 54.54. Found: H,
5.06; C, 54.49.
1
yellow liquid. H NMR (400 MHz, CDCl3) d 7.62 (d, JZ
8.8 Hz, 2H), 7.17 (d, JZ8.8 Hz, 2H), 3.75 (q, JZ7.2 Hz,
4H), 1.26 (t, JZ7.2 Hz, 6H).
4.1.3. 4-Ethynyl-1-diethyltriazenylbenzene (3). First, 4-
[(trimethylsilyl)ethynyl]-1-diethyltriazenylbenzene was
synthesized according to procedure A. Used were 2
(1.65 g, 5.4 mmol), triethylamine (8.0 mL), (trimethylsilyl)-
acetylene (0.92 mL, 6.50 mmol), bis(dibenzylideneaceto-
ne)palladium(0) (0.155 g, 0.27 mmol), triphenylphosphine
(0.354 g, 1.35 mmol) and copper iodide (0.103 g,
0.54 mmol) for 1 day. The crude product was purified by
flash chromatography on neutral alumina by first using 20:1
hexane/dichloromethane and then slowly increasing to 8:1
hexane/dichloromethane to afford 1.40 g (95%) of 4-
[(trimethylsilyl)ethynyl]-1-diethyltriazenylbenzene as a
4.1.7. Tetramer (7). See procedure A. Compound 5 (0.35 g,
0.97 mmol), 6 (0.43 g, 0.97 mmol), bis(dibenzylideneace-
tone)palladium(0) (0.0288 g, 0.05 mmol), triphenyl-
phosphine (0.0629 g, 0.24 mmol), copper(I) iodide
(0.0184 g, 0.09 mmol), THF (6 mL) and triethylamine
(1 mL) for 2 days afforded 0.62 g (90%) of 7 as a yellow
waxy solid after flash chromatography on neutral alumina
by first using hexane and then slowly increasing to 9:1
hexane/dichloromethane. 1H NMR (600 MHz, CDCl3) d
7.48 (d, JZ8.4 Hz, 2H), 7.46 (s, 4H), 7.40 (d, JZ8.4 Hz,
2H), 7.03 (s, 1H), 7.01 (s, 1H), 3.77 (q, JZ7.2 Hz, 4H), 2.72
(t, JZ7.2 Hz, 2H), 2.65 (t, JZ7.2 Hz, 2H), 1.65–1.59 (m,
4H), 1.41–1.34 (m, 4H), 1.26 (br s, 6H), 0.97–0.93 (m, 6H),
0.26 (s, 9H). 13C NMR (CDCl3, 150 MHz) d 151.24, 148.63,
148.00, 132.91, 132.48, 132.12, 131.97, 131.28, 131.11,
124.02, 123.07, 122.56, 122.41, 120.41, 120.24, 120.18,
119.10, 118.59, 102.25, 96.80, 95.71, 94.89, 93.30, 84.70,
84.44, 82.38, 32.19, 31.99, 29.16, 28.98, 22.20, 22.13,
13.87, 13.78. LDI-MS (m/z): 698 (MC), 669 (MKC2H5),
598 (MKEt2N3). Anal. Calcd for C43H47N3S2Si: H, 6.79; C,
74.00; N, 6.02. Found: H, 6.88; C, 73.87; N, 5.76.
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yellow–orange waxy solid. H NMR (400 MHz, CDCl3) d
7.42 (d, JZ8.8 Hz, 2H), 7.34 (d, JZ8.8 Hz, 2H), 3.76 (q,
JZ7.2 Hz, 4H), 1.26 (t, JZ7.2 Hz, 6H), 0.25 (s, 9H).
Then, 3 was synthesized according to procedure B. 4-
[(Trimethylsilyl)ethynyl]-1-diethyltriazenylbenzene (0.42 g,
1.50 mmol), methanol (25 mL), and potassium carbonate
(0.69 g, 5 mmol) afforded 0.30 g (100%) of 3 as a yellow
oil. 1H NMR (400 MHz, CDCl3) d 7.45 (d, JZ8.8 Hz, 2H),
7.36 (d, JZ8.8 Hz, 2H), 3.77 (q, JZ7.2 Hz, 4H), 2.95 (s,
1H), 1.27 (t, JZ7.2 Hz, 6H).
4.1.8. Terminal alkynyl tetramer (8). See procedure B.
Compound 7 (0.30 g, 0.43 mmol), methanol (10 mL),
dichloromethane (5 mL) and potassium carbonate (0.24 g,
1.73 mmol) afforded 0.266 g (98%) of 8 as a yellow solid.
1H NMR (400 MHz, CDCl3) d 7.47 (br s, 6H), 7.40 (d, JZ
8.4 Hz, 2H), 7.04 (s, 2H), 3.27 (q, JZ7.2 Hz, 4H), 3.47 (s,
1H), 2.73–2.68 (m, 4H), 1.65–1.61 (m, 4H), 1.41–1.37 (m,
4H), 1.28 (m, 12H), 0.97–0.92 (m, 6H).
4.1.4. Dimer (4). See procedure A. Compound 1 (2.54 g,
7.0 mmol), 3 (1.31 g, 6.5 mmol), bis(dibenzylideneacetone)-
palladium(0) (0.20 g, 0.35 mmol), triphenylphosphine
(0.46 g, 1.75 mmol), copper(I) iodide (0.13 g, 0.70 mmol)
and triethylamine (30 mL) for 36 h afforded 2.69 g (95%) of
4 as a yellow sticky liquid after flash chromatography on
1
neutral alumina (hexane). H NMR (600 MHz, CDCl3) d
7.45 (d, JZ8.4 Hz, 2H), 7.39 (d, JZ8.4 Hz, 2H), 6.98 (s,
1H), 3.77 (q, JZ7.2 Hz, 4H), 2.65 (t, JZ7.8 Hz, 2H), 1.60
(quint, JZ7.2 Hz, 2H), 1.35 (sext, JZ7.2 Hz, 2H), 1.27 (br
s, 6H), 0.94 (t, JZ7.2 Hz, 3H), 0.26 (s, 9H). 13C NMR
(CDCl3, 150 MHz) d 151.27, 148.64, 132.34, 132.18,
123.44, 120.44, 119.42, 118.69, 101.82, 97.05, 94.33,
82.39, 32.16, 32.05, 29.05, 22.18, 13.91, 13.81. LDI-MS
(m/z): 436 (MC), 407 (MKC2H5), 363 (MKTMS), 336
(MKEt2N3). Anal. Calcd for C25H33N3SSi: H, 7.64; C,
68.93; N, 9.65. Found: H, 7.58; C, 69.02; N, 9.43.
4.1.9. Iodide tetramer (9). See procedure C. Compound 7
(0.30 g, 0.43 mmol) and iodomethane (10 mL) for 24 h
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afforded 0.31 g (100%) of 9 as a yellow solid. H NMR
(600 MHz, CDCl3) d 7.69 (d, JZ8.4 Hz, 2H), 7.47 (s, 4H),
7.22 (d, JZ8.4 Hz, 2H), 7.07 (s, 1H), 7.02 (s, 1H), 2.73 (t,
JZ7.2 Hz, 2H), 2.65 (t, JZ7.2 Hz, 2H), 1.65–1.59 (m, 4H),
1.40–1.35 (m, 4H), 0.97–0.93 (m, 6H), 0.26 (s, 9H). 13C
NMR (CDCl3, 150 MHz) d 148.69, 148.07, 137.59, 133.21,
133.00, 132.83, 131.37, 131.22, 123.05, 122.95, 122.66,