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M. D’hooghe et al. / Tetrahedron 60 (2004) 3637–3641
(NaCl, cm21): n¼1672, 1591, 1460, 1319, 1228, 1157,
1086, 1026. MS (70 eV) m/z (%): 225 (Mþ, 0.5); 197 (1);
155 (4); 91 (24); 70 (100); 65 (14); 51 (3). Anal. Calcd for
C11H15NO2S: C 58.64%; H 6.71%; N 6.22%. Found: C
58.77%; H 6.85%; N 6.13%.
(CH3Ar); 22.46, 24.89, 31.55 and 35.02 (2£(CH3(CH2)4));
54.14 (CHN); 127.06 and 129.50 (2£HCortho and 2£
HCmeta); 138.54 (CH3Carom,quat); 143.03 (Carom,quat). IR
(NaCl, cm21): n¼3277, 2936, 2853, 1598, 1457, 1423,
1324, 1153. MS (70 eV) m/z (%): 326 (Mþ, 1); 255 (74);
184 (5); 171 (8); 155 (62); 147 (5); 139 (4); 107 (5); 91
(100); 77 (3); 65 (24); 56 (28). Anal. Calcd for
C18H31NO2S: C 66.42%; H 9.60%; N 4.30%. Found: C
66.58%; H 9.76%; N 4.21%.
4.2.2. 1-(4-Methylbenzenesulfonyl)-2-pentylaziridine 5b.
1
Yield 67%, colorless liquid. H NMR (270 MHz, CDCl3):
d 0.81 (3H, t, J¼5.9 Hz, CH3CH2); 1.11–1.56 (8H, m,
CH3(CH2)4); 2.05 (1H, d, J¼4.3 Hz, (HtransCH)N); 2.42
(3H, s, CH3Ar); 2.62 (1H, d, J¼6.9 Hz, (HCHcis)N); 2.65–
2.72 (1H, m, CHN); 7.32 and 7.82 (4H, 2£d, J¼8.0 Hz,
2£HCortho and 2£HCmeta). 13C NMR (68 MHz, CDCl3): d
13.84 (CH3CH2); 21.58 (CH3Ar); 22.43, 26.43, 31.16 and
31.27 (CH3(CH2)4); 33.75 (CH2N); 40.48 (CHN); 127.99 and
129.61 (2£HCortho and 2£HCmeta); 135.20 (CH3Carom,quat);
144.44 (Carom,quat). IR (NaCl, cm21): n¼2931, 2863, 1598,
1465, 1324, 1240, 1154. Anal. Calcd for C14H21NO2S: C
62.89%; H 7.92%; N 5.24%. Found: C 63.04%; H 8.11%; N
5.12%.
4.3.3. N-(1-Ethylpropyl)benzenesulfonamide 6c. Yield
78%, colorless liquid. Flash chromatography on silica
gel: Acetonitrile/Chloroform (1/1), Rf¼0.75. 1H NMR
(270 MHz, CDCl3): d 0.75 (6H, t, J¼7.4 Hz, (CH3CH2)2);
1.26–1.56 (4H, m, (CH3CH2)2); 3.08–3.16 (1H, m, CHN);
4.82 (1H, br d, J¼7.9 Hz, NH); 7.47–7.62 (3H, m,
2£HCmeta and HCpara); 7.89–7.98 (2H, m, 2£HCortho).
13C NMR (68 MHz, CDCl3): d 9.61 ((CH3CH2)2); 27.19
((CH3CH2)2); 56.78 (CHN); 126.90 and 128.95 (2£HCortho
and 2£HCmeta); 132.36 (HCpara); 141.42 (Carom,quat). IR
(NaCl, cm21):n¼3275, 1450, 1312, 1164. MS (70 eV) m/z
(%): 227 (Mþ, 0.2); 198 (100); 141 (48); 77 (41); 51 (9).
Anal. Calcd for C11H17NO2S: C 58.12%; H 7.54%; N
6.16%. Found: C 58.20%; H 7.68%; N 6.05%.
4.3. Synthesis of tosylamides 6
As a representative example, the synthesis of N-(1-ethyl-
propyl)-4-methylbenzenesulfonamide 6a is described. To a
solution of copper iodide (0.99 g, 5.2 mmol, 3 equiv.) in dry
diethyl ether (35 mL), methyllithium (6.5 mL, 10.4 mmol,
6 equiv., 1.6 M in ether) was added dropwise via a syringe at
278 8C and under nitrogen atmosphere, and the solution
was further stirred for 30 min at 278 8C. Subsequently, a
solution of 1-(4-methylbenzenesulfonyl)-2-(bromomethyl)-
aziridine 1a (0.50 g, 1.7 mmol) in diethyl ether (5 mL) was
added at 278 8C, after which the mixture was stirred for 5
more hours at room temperature. The reaction mixture was
then filtered over Celitew, and the filtrate was extracted with
water and ether (3£50 mL). Drying (MgSO4), filtration and
evaporation in vacuo afforded N-(1-ethylpropyl)-4-methyl-
benzenesulfonamide 6a (0.32 g, 79%).
4.3.4. N-(1-Pentylhexyl)benzenesulfonamide 6d. Yield
68%, colorless liquid. Flash chromatography on silica gel:
EtOAc/Hexane (1/1), Rf¼0.42. 1H NMR (270 MHz,
CDCl3): d 0.81 (6H, t, J¼6.9 Hz, 2£CH3); 1.11–1.42
(16H, m, 2£(CH3(CH2)4)); 3.17–3.25 (1H, m, CHN); 5.02
(1H, br d, J¼8.2 Hz, NH); 7.29–7.92 (5H, m, C6H5). 13C
NMR (68 MHz, ref¼CDCl3): d 13.86 (2£CH3); 22.36,
24.80, 31.45 and 34.88 (2£(CH3(CH2)4)); 54.16 (CHN);
126.88 and 128.81 (2£HCortho and 2£HCmeta); 132.18
(HCpara); 141.46 (Carom,quat). IR (NaCl, cm21): n¼3282,
1587, 1448, 1325, 1162. MS (70 eV) m/z (%): 311 (Mþ,
0.1); 240 (100); 170 (9); 141 (33); 77 (36); 51 (4). Anal.
Calcd for C17H29NO2S: C 65.55%; H 9.38%; N 4.50%.
Found: C 65.75%; H 9.49%; N 4.40%.
4.3.1. N-(1-Ethylpropyl)-4-methylbenzenesulfonamide
6a. Yield 79%, colorless liquid. Flash chromatography on
silica gel: Acetone/chloroform (1:1), Rf¼0.70. 1H NMR
(270 MHz, CDCl3): d 0.71 (6H, t, J¼7.3 Hz, (CH3CH2)2);
1.21–1.45 (4H, m, (CH3CH2)2); 2.37 (3H, s, CH3Ar);
3.01–3.09 (1H, m, CHN); 4.94 (1H, br s, NH); 7.24 and
7.74 (4H, 2£d, J¼8.2 Hz, 2£HCortho and 2£HCmeta). 13C
NMR (68 MHz, CDCl3): d 9.61 ((CH3CH2)2); 21.49
(CH3Ar); 27.15 ((CH3CH2)2); 56.69 (CHN); 126.99 and
129.52 (2£HCortho and 2£HCmeta); 138.59 (CH3Carom,quat);
142.98 (Carom,quat). IR (NaCl, cm21): n¼3350, 3287, 1596,
1456, 1413, 1327, 1157. MS (70 eV) m/z (%): no Mþ; 155
(1); 123 (4); 121 (13); 119 (15); 88 (52); 86 (94); 84 (100);
51 (21); 49 (83); 47 (77). Anal. Calcd for C12H19NO2S: C
59.72%; H 7.93%; N 5.80%. Found: C 59.88%; H 8.10%; N
5.74%.
4.3.5. Synthesis of N-(1-ethylhexyl)-4-methylbenzene-
sulfonamide 7. This compound was prepared in a two-
step procedure starting from 1-(4-methylbenzenesulfonyl)-
2-(bromomethyl)aziridine 1a via 1-(4-methylbenzenesulfo-
nyl)-2-pentylaziridine 5b, analogous to the procedures
described above.
Yield 63%, colorless liquid. 1H NMR (270 MHz, CDCl3): d
0.75–0.84 (6H, m, 2£CH3); 1.12–1.49 (10H, m, (CH3CH2-
CH(CH2)4CH3); 2.42 (3H, s, CH3Ar); 3.27–3.33 (1H, m,
CHN); 4.81 (1H, br s, NH); 7.29 and 7.79 (4H, 2£d, J¼7.2,
8.2 Hz, 2£HCortho and 2£HCmeta). 13C NMR (68 MHz,
CDCl3): d 13.94 (2£CH3); 21.47 (CH3Ar); 22.46
(2£CH3CH2); 24.89 (CH3CH2CH2); 31.55 (CH3(CH2)2-
CH2); 34.92 (CH3(CH2)3CH2); 55.35 (CHN); 127.04 and
129.50 (2£HCortho and 2£HCmeta); 138.56 (CH3Carom,quat);
143.00 (Carom,quat). IR (NaCl, cm21): n¼3282, 1599,
1494, 1455, 1429, 1326, 1157, 1094, 1031. MS (70 eV)
m/z (%): no Mþ; 212 (5); 166 (4); 140 (4); 126 (35); 112
(8); 97 (12); 86 (16); 85 (61); 84 (13); 71 (100); 69 (13); 57
(98); 55 (19). Anal. Calcd for C15H25NO2S: C 63.56%;
H 8.89%; N 4.94%. Found: C 63.68%; H 9.02%; N
4.91%.
4.3.2. N-(1-Pentylhexyl)-4-methylbenzenesulfonamide
6b. Yield 77%, colorless liquid. 1H NMR (270 MHz,
CDCl3): d 0.81 (6H, t, J¼6.6 Hz, 2£CH3CH2); 1.05–1.39
(16H, m, 2£(CH3(CH2)4)); 2.41 (3H, s, CH3Ar); 3.17–3.19
(1H, m, CHN); 4.57 (1H, br d, J¼8.3 Hz, NH); 7.28 and
7.41 (4H, 2£d, J¼8.0 Hz, 2£HCortho and 2£HCmeta). 13C
NMR (68 MHz, CDCl3): d 13.93 (2£CH3CH2); 21.46