8908
J. R. Fotsing et al. / Tetrahedron 61 (2005) 8904–8909
(neat substance can be very explosive) and the residue was
chromatographed on silica gel with Et2O/n-hexane 1:9 to
afford E-13 (181 mg, 0.69 mmol, 26%, yellow oil), Z-13
(200 mg, 0.76 mmol, 28%, yellow oil) and a mixture of
E-13 and Z-13 (11 mg, 0.04 mmol, 1.5%) after very careful
removal of the solvent under vacuum.
for 20 min at room temperature, the solvent was partially
removed. The residue was filtrated through silica gel with
Et2O, and the solvent was partially evaporated. By standing
at K18 8C, the product crystallized slowly. The solid was
filtrated and washed with Et2O/n-hexane (3:2). The filtrate
was concentrated, dissolved in a small amount of Et2O, and
crystallization was repeated for several times to give the
desired products E/Z-16 (100 mg, 0.36 mmol, 7.6%, E/ZZ
2:3) as yellow-orange solid. IR (CDCl3, mixture): n~Z2110
E-(2,3-Diazidoprop-2-enylsulfonyl)-benzene (E-13): IR
1
(CDCl3): 2096 (N3), 1322 (SO2), 1153 (SO2) cmK1. H
NMR (CDCl3): d 3.97 (s, 2H, H-10), 6.23 (s, 1H, H-30), 7.60
(m, 2H, m-Ph), 7.70 (m, 1H, p0-Ph), 7.96 (m, 2H, o-Ph). 13C
NMR (CDCl3): d 54.22 (t, C-1 ), 118.30 (s, C-20), 120.29 (d,
C-30), 128.78 (d, 2C), 128.98 (d, 2C), 134.28 (d, p-Ph),
138.15 (s, i-Ph).
(N3), 1325 (SO2), 1139 (SO2) cmK1 1H NMR (CDCl3,
.
mixture): d 1.77 (s, 3H, H3C, E-isomer), 1.83 (s, 3H, H3C,
Z-isomer), 3.92 (s, 2H, H-10, Z-isomer), 4.12 (s, 2H, H-10,
E-isomer), 7.61 (m, 2!2H, m-Ph), 7.71 (m, 2!1H, p-Ph),
7.91 (m, 2!2H, o-Ph). 13C NMR (CDCl3, mixture): d 12.68
(q, H3C), 14.47 (q, H3C), 53.30 (t, C-10), 56.30 (t, C-10),
109.61 (s), 111.36 (s), 126.79 (s), 127.33 (s), 128.27 (d, 2C),
128.62 (d, 2C), 128.66 (d, 2C), 129.48 (d, 2C), 134.41 (d),
134.59 (d), 136.92 (s, 2C).
Z-(2,3-Diazidoprop-2-enylsulfonyl)-benzene (Z-13): IR
1
(CDCl3): 2117 (N3), 1324 (SO2), 1157 (SO2) cmK1. H
NMR (CDCl3): d 3.71 (s, 2H, H-10), 5.89 (s, 1H, H-30), 7.61
(m, 2H, m-Ph), 7.70 (m, 1H, p0-Ph), 7.92 (m, 2H, o-Ph). 13C
NMR (CDCl3): d 58.52 (t, C-1 ), 115.27 (s, C-20), 120.73 (d,
C-30), 128.51 (d, 2C), 129.39 (d, 2C), 134.39 (d, p-Ph),
137.82 (s, i-Ph).
4.1.8. E/Z-(2,3-Diazidobut-2-enylsulfonyl)-benzene (E/Z-
16) and E/Z-(2,3-Diazidobut-1-enylsulfonyl)-benzene
(E/Z-17). Compound 1518 (400 mg, 1.70 mmol) in
CH2Cl2 (25 mL) was treated with TMGA (0.30 g,
1.90 mmol) at K10 8C over a period of 2 min. Stirring
was continued at K5 8C for 2 h. The solvent was partially
removed, and the residue was chromatographed on silica gel
with Et2O/n-hexane (3:2). E-17 was obtained as major
product in a mixture with E-16 (150 mg, 0.54 mmol, 32%,
E-17/E-16Z18:1) and then Z-17 as major product in a
mixture with Z-16 (90.0 mg, 0.324 mmol, 19%, Z-17/Z-
16Z6:1). When the reaction was executed at 0 8C instead of
room temperature, E-17/E-16 (4:1) and Z-17/Z-16 (6:1)
were obtained after chromatography. For the data of E/Z-16,
see Section 4.1.7.
4.1.5. (E-3-Phenylsulfonylprop-1-en-1,2-diyl)-bis-4,5,6,7,
8,9-hexahydro-1H-cyclooctatriazole (E-14). Compound
E-14 (76%) was obtained from E-13 by analogy to the
procedure described for E-10. White solid: mp (CH2Cl2/
Et2O) 158–159 8C. 1H NMR (CDCl3): d 1.52 (m, 8H), 1.82
(m, 8H), 2.65 (m, 2H), 2.92 (m, 6H), 5.36 (s, 2H, H-30), 7.02
(s, 1H, H-10), 7.45 (m, 2H, m-Ph), 7.54 (m, 1H, p-Ph), 7.81
(m, 2H, o-Ph). 13C NMR (CDCl3): d 21.73 (t), 22.55 (t),
24.19 (t), 24.20 (t), 24.30 (t), 25.01 (t), 25.41 (t), 25.54 (t),
26.03 (t), 27.48 (t), 27.70 (t), 28.10 (t), 57.51 (t, C-30),
121.86 (s), 124.36 (d), 128.09 (d, 2C), 128.95 (d, 2C),
133.81 (d), 134.40 (s), 134.79 (s), 138.78 (s, i-Ph), 144.57
(s), 145.30 (s). Anal. Calcd for C25H32N6O2S (480.63): C,
62.47; H, 6.71; N, 17.49. Found: C, 62.67; H, 6.61; N, 17.47.
E-(2,3-Diazidobut-1-enylsulfonyl)-benzene (E-17): IR
(CDCl3, mixture of E-17/E-16): 2113 (N3), 1246 (N3),
1307 (SO2), 1153 (SO2) cmK1. 1H NMR (CDCl3): d 1.40 (d,
3JZ6.6 Hz, 3H, H3C), 5.49 (q, 3JZ6.6 Hz, 1H, H-30), 6.02
(s, 1H, H-10), 7.58 (m, 2H, m-Ph), 7.66 (m, 1H, p-Ph), 7.91
(m, 2H, o-Ph). 13C NMR (CDCl3): d 17.36 (q, H3C), 52.16
(d, C-30), 115.70 (d, C-10), 127.14 (d, 2C), 129.507 (d, 2C),
133.84 (d, p-Ph), 141.32 (s, i-Ph), 154.35 (s, C-2 ).
4.1.6. (Z-3-Phenylsulfonylprop-1-en-1,2-diyl)-bis-4,5,6,7,
8,9-hexahydro-1H-cyclooctatriazole (Z-14). Compound
Z-14 (72%) was obtained from Z-13 by analogy to the
procedure described for E-10. White solid: mp (CH2Cl2/
Et2O) 184–185 8C. 1H NMR (CDCl3): d 1.43 (m, 10H), 1.70
(m, 4H), 1.78 (m, 2H), 2.27 (br s, 2H), 2.63 (m, 2H), 2.84
(m, 4H), 4.56 (s, 2H, H-30), 7.16 (s, 1H, H-10), 7.54 (m, 2H,
m-Ph), 7.65 (m, 1H, p-Ph), 7.82 (m, 2H, o-Ph). 13C NMR
(CDCl3): d 21.44 (t), 21.93 (t), 23.96 (t), 24.10 (t), 24.19 (t),
24.36 (t), 24.69 (t), 25.070 (t), 25.91 (t), 26.04 (t), 27.04 (t),
27.99 (t), 60.94 (t, C-3 ), 119.52 (s), 122.91 (d), 127.85 (d,
2C), 129.42 (d, 2C), 134.32 (d), 134.35 (s), 135.53 (s),
138.35 (s, i-Ph), 144.13 (s), 144.43 (s). Anal. Calcd for
C25H32N6O2S (480.63): C, 62.47; H, 6.71; N, 17.49. Found:
C, 61.81; H, 6.72; N, 17.30.
Z-(2,3-Diazidobut-1-enylsulfonyl)-benzene (Z-17): IR
(CDCl3, mixture of Z-17/Z-16Z6:1): 2121 (N3), 1309
(SO2), 1151 (SO2) cmK1. 1H NMR (CDCl3): d 1.51 (d, 3JZ
3
6.6 Hz, 3H, H3C), 4.19 (q, JZ6.6 Hz, 1H, H-30), 5.98 (s,
H-10), 7.55 (m, 2H, m-Ph), 7.63 (m, 1H, p-Ph), 7.98 (m, 2H,
o-Ph). 13C NMR (CDCl3): d 17.82 (q, H3C), 58.50 (d, C-30),
115.82 (d, C-10), 127.72 (d, 2C), 129.03 (d, 2C), 133.58 (d,
p-Ph), 141.29 (s, i-Ph), 148.77 (s, C-20).
4.1.9. (E-1-Phenylsulfonylbut-1-en-2,3-diyl)-bis-4,5,6,7,
8,9-hexahydro-1H-cyclooctatriazole (E-18). A mixture
(85.0 mg, 0.306 mmol) of E-16 and E-17 (1:18) in CH2Cl2
(10 mL) was stored at room temperature over a period of
4.1.7. E/Z-(2,3-Diazidobut-2-enylsulfonyl)-benzene (E/Z-
16). Compound 1518 (1.12 g, 4.77 mmol) in CHCl3 (10 mL)
was treated with DABCO (1.07 g, 9.5 mmol) at 18 8C.
Stirring was continued at the same temperature for
additional 90 min. The solvent was partially removed, and
the residue was filtrated through silica gel with Et2O. The
etheric phase, which contained the allenyl azide 19,18 was
concentrated and dissolved rapidly in CH2Cl2 (10 mL).
Then TMGA (0.75 g, 4.77 mmol) was added. After stirring
1
48 h. The H NMR spectra proved the total decomposition
of E-16. The mixture was then treated with cyclooctyne
according to the procedure described for E-10 and
chromatographed to give E-18 (136 mg, 0.275 mmol,
1
90%) as yellow oil. H NMR (CDCl3): d 1.27–1.90 (m,
18H), 2.03 (d, 3JZ7.2 Hz, 3H, H3C), 2.76 (m, 6H), 6.33 (s,