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4.3.4. N-Allyl-N-(2,2-dichlorovinyl)-4-methyl-benzene-
sulfonamide (7c). As described for compound 7b starting
from compound 3c, yield 97% (3.93 mmol scale, 1.17 g),
colorless crystalline solid. Rf 0.41 (PE/EtOAc 5:1); mp
21.5, 52.0, 61.0 (C^CH), 72.9 (C^CH), 127.3 (2C), 129.7
(2C), 135.9, 144.5. Anal. Calcd for C12H15NO2S: C 60.73, H
6.37, N 5.90; Found: C 60.88, H 6.48, N 5.99.
1
90 8C; H NMR (300 MHz, CDCl3): dZ2.43 (s, 3H), 4.00
4.4.2. N-Butyl-N-ethynyl-4-methyl-benzenesulfonamide
(1a). As described for compound 1b starting from
compound 7a, yield 86% (1.18 mmol scale, 255 mg),
(d, JZ6.3 Hz, 2H), 5.15 (dq, JZ10.0, 1.0 Hz, 1H), 5.18 (dq,
JZ17.1, 1.2 Hz, 1H), 5.68 (ddt, JZ17.0, 10.2, 6.3 Hz, 1H),
6.31 (s, 1H), 7.32 (d, JZ8.1 Hz, 2H), 7.69 (d, JZ8.3 Hz,
2H); 13C NMR (75 MHz, CDCl3) dZ21.6, 51.7, 119.4,
124.3, 124.8, 127.4 (2C), 129.9 (2C), 131.9, 135.7, 144.2.
Anal. Calcd for C12H13Cl2NO2S: C 47.07, H 4.28, N 4.57;
Found: C 47.01, H 4.27, N 4.42.
1
yellow oil. Rf 0.41 (PE/EtOAc 5:1); H NMR (200 MHz,
CDCl3): dZ0.83 (t, JZ7.3 Hz, 3H), 1.21–1.51 (m, 4H),
2.37 (s, 3H), 2.65 (s, 1H), 3.22 (t, JZ7.2 Hz, 2H), 7.28 (d,
JZ8.0 Hz, 2H), 7.72 (d, JZ8.0 Hz, 2H); 13C NMR
(50 MHz, CDCl3) dZ13.5, 19.4, 21.6, 29.6, 50.9, 58.9,
76.4, 127.6, 129.7, 134.6, 144.6.
4.3.5.
N-(2,2-Dichlorovinyl)-N-(2-methyl-allyl)-4-
methyl-benzenesulfonamide (7d). As described for com-
pound 7b starting from compound 3d, yield 97%
(1.13 mmol scale, 350 mg), colorless crystalline solid. Rf
0.43 (PE/EtOAc 5:1); mp 84 8C; 1H NMR (300 MHz,
CDCl3): dZ1.76 (s, 3H), 2.44 (s, 3H), 3.88 (s, 2H), 4.84–
4.87 (m, 1H), 4.90–4.93 (m, 1H), 6.20 (s, 1H), 7.31–7.36
(m, 2H), 7.67–7.72 (m, 2H); 13C NMR (75 MHz, CDCl3)
dZ19.8, 21.5, 55.2, 115.1, 124.7, 125.2, 127.2 (2C), 129.8
(2C), 135.4, 139.4, 144.2. Anal. Calcd for C13H15Cl2NO2S:
C 48.76, H 4.72, N 4.37; Found: C 48.95, H 4.89, N 4.23.
4.4.3. N-Allyl-N-ethynyl-4-methyl-benzenesulfonamide
(1c). As described for compound 1b starting from
compound 7c, yield 81% (3.78 mmol scale, 721 mg),
colorless crystalline solid. Rf 0.25 (PE/EtOAc 5:1); mp
1
68–70 8C; H NMR (200 MHz, CDCl3): dZ2.37 (s, 3H),
2.65 (s, 1H), 3.88 (dt, JZ6.2, 1.2 Hz, 2H), 5.11–5.24 (m,
2H), 5.66 (ddt, JZ17.1, 10.1, 6.3 Hz, 1H), 7.29 (m, 2H),
7.74 (m, 2H); 13C NMR (50 MHz, CDCl3) dZ21.5, 53.9,
59.2, 75.8, 120.0, 127.7 (2C), 129.7 (2C), 130.5, 134.6,
144.8. Anal. Calcd for C12H13NO2S: C 61.25, H 5.57, N
5.95; Found: C 61.35, H 5.41, N 5.89.
4.3.6. N-(2,2-Dichlorovinyl)-N-benzyl-4-methyl-benzene-
sulfonamide (7e). As described for compound 7b starting
from compound 3e, yield 96% (1.76 mmol scale, 600 mg),
colorless crystalline solid. Rf 0.40 (PE/EtOAc 5:1); mp
126 8C; 1H NMR (200 MHz, CDCl3): dZ2.43 (s, 3H), 4.53
(s, 2H), 6.21 (s, 1H), 7.28 (m, 5H), 7.34 (d, JZ8.3 Hz, 2H),
7.72 (d, JZ8.3 Hz, 2H); 13C NMR (50 MHz, CDCl3) dZ
21.5, 52.6, 124.7, 125.6, 127.2, 127.9, 128.3, 128.5, 129.8,
135.0, 135.6, 144.2. Anal. Calcd for C16H15Cl2NO2S: C
53.94, H 4.24, N 3.93; Found: C 53.83, H 4.12, N 3.87.
4.4.4. N-Ethynyl-N-(2-methyl-allyl)-4-methyl-benzene-
sulfonamide (1d). As described for compound 1b starting
from compound 7d, yield 95% (1.09 mmol scale, 257 mg),
colorless crystalline solid. Rf 0.34 (PE/EtOAc 5:1); mp
1
69 8C; H NMR (300 MHz, CDCl3): dZ1.72 (s, 3H), 2.46
(s, 3H), 2.71 (s, 1H), 3.86 (s, 2H), 4.91–4.94 (m, 1H), 4.95–
4.98 (m, 1H), 7.33–7.38 (m, 2H), 7.79–7.84 (m, 2H); 13C
NMR (75 MHz, CDCl3) dZ19.5, 21.6, 57.5, 59.0, 75.8,
115.8, 127.7 (2C), 129.7 (2C), 134.5, 138.4, 144.7. Anal.
Calcd for C13H15NO2S: C 62.62, H 6.06, N 5.62; Found: C
62.32, H 5.90, N 5.77.
4.3.7. N-(2,2-Dichlorovinyl)-N-phenyl-4-methyl-benzene-
sulfonamide (7f). As described for compound 7b starting
from compound 3f, yield 81% (1 mmol scale, 276 mg),
colorless crystalline solid. Mp 115–116 8C; 1H NMR
(200 MHz, CDCl3): dZ2.43 (s, 3H), 6.97 (s, 1H), 7.06
(m, 2H), 7.28 (m, 5H), 7.47 (m, 2H); 13C NMR (50 MHz,
CDCl3) dZ21.6, 118.2, 126.2, 127.7, 128.0, 128.3, 128.9,
129.6, 134.1, 138.2, 144.6. Anal. Calcd for C15H13Cl2NO2-
S: C 52.64, H 3.83, N 4.09; Found: C 52.83, H 3.93, N 3.95.
4.4.5. N-Benzyl-N-ethynyl-4-methyl-benzenesulfon-
amide (1e). As described for compound 1b starting from
compound 7e, yield 80% (1.61 mmol scale, 367 mg),
colorless crystalline solid. Rf 0.34 (PE/EtOAc 5:1); mp
102–103 8C; 1H NMR (300 MHz, CDCl3): dZ2.44 (s, 3H),
2.67 (s, 1H), 4.49 (s, 2H), 7.27–7.35 (m, 7H), 7.73–7.79 (m,
2H); 13C NMR (75 MHz, CDCl3) dZ21.6, 55.2, 59.6, 76.2,
127.6, 128.3, 128.5, 128.6, 129.7, 134.2, 134.6, 144.7. Anal.
Calcd for C16H15NO2S: C 67.34, H 5.30, N 4.91; Found: C
67.02, H 5.32, N 5.06.
4.4. Syntheses of ynamides 1
4.4.1. N-Ethynyl-N-isopropyl-4-methyl-benzenesulfon-
amide (1b) (representative procedure for the synthesis
of ynamides 1). A solution of dichlorovinylamide 7b
(205 mg, 0.66 mmol) in THF (3.3 mL) was cooled to
K78 8C and treated with n-BuLi (0.96 mL, 1.53 M in hexane,
1.46 mmol). The mixture was warmed to K30 8C within 2 h
and then MeOH (135 mL) was added. Dilution with TBME
(10 mL) and workup using satd NaHCO3 (5 mL) gave a
yellow crude product, which was purified by flash chroma-
tography on basic alox (pentane/TBME 6:1) to yield the
desiredynamide1b(146 mg, 93%)asapale yellowcrystalline
solid. Rf 0.58 (PE/EtOAc 5:1); mp 95–97 8C; 1H NMR
(300 MHz, CDCl3): dZ1.11 (d, JZ6.6 Hz, 6H), 2.45 (s, 3H),
2.80 (s, 1H), 4.13 (sept, JZ6.6 Hz, 1H), 7.32–7.37 (m, 2H),
7.79–7.84 (m, 2H); 13C NMR (75 MHz, CDCl3) dZ20.4,
4.4.6. N-Ethynyl-N-phenyl-4-methyl-benzenesulfon-
amide (1f). As described for compound 1b starting from
compound 7f, yield 97% (1.52 mmol scale, 401 mg), pale
yellow crystalline solid. Rf 0.30 (PE/EtOAc 5:1); mp 86–
1
87 8C; H NMR (200 MHz, CDCl3): dZ2.44 (s, 3H), 2.84
(s, 1H), 7.21–7.37 (m, 7H), 7.54–7.62 (m, 2H); 13C NMR
(50 MHz, CDCl3) dZ21.6, 58.9, 76.4, 126.1, 128.1, 128.3,
129.0, 129.5, 132.7, 138.1, 145.1. Anal. Calcd for
C15H13NO2S: C 66.40, H 4.83, N 5.16; Found: C 66.25, H
4.61, N 5.07.