B. Das et al. / Tetrahedron Letters 48 (2007) 7930–7933
7933
bonylamino sulfones and allyltrimethylsilane in the
presence of a catalytic amount of indium chloride.
Compound 3k: White solid; mp 65–67 ꢁC; IR (KBr):
mmax 3363, 1687, 1525, 1463, 1251 cmÀ1 1H NMR
;
(CDCl3, 200 MHz): d 7.82–7.61 (5H, m), 7.48–7.20
(7H, m), 5.62 (1H, m), 5.12–4.99 (5H, m), 4.80 (1H, br
s), 2.62–2.51 (2H, m); 13C NMR (CDCl3, 50 MHz): d
155.8, 139.9, 135.8, 133.0, 132.7, 132.6, 128.4, 128.0,
127.9, 127.8, 126.0, 125.5, 125.2, 124.6, 118.4, 66.8,
54.3, 40.7; FABMS: m/z 354 [M+Na]+Å; Anal. Calcd
for C22H21NO2: C, 79.76; H, 6.34; N, 4.23. Found: C,
79.87; H, 6.28; N, 4.29.
General experimental procedure: Allyltrimethylsilane
(1.5 mmol) was added drop-wise to a solution of N-
alkoxycarbonylamino p-tolylsulfone (1 mmol) and InCl3
(5 mol %) in CH2Cl2 (5 mL) under nitrogen. The mix-
ture was stirred and the reaction was monitored by
TLC. After completion, the reaction was quenched with
distilled water (5 mL) and the mixture was extracted
with EtOAc (3 · 10 mL). The combined organic por-
tions were washed with water (2 · 10 mL) and saturated
aqueous NH4Cl (2 · 10 mL), dried over anhydrous
Na2SO4 and concentrated under vacuum. The crude
product was subjected to column chromatography
(silica gel, hexane–EtOAc, 92:8 to 95:5) to obtain pure
protected homoallylic amine.
Compound 3o: White solid; mp 40–42 ꢁC; IR (KBr):
mmax 3331, 1700, 1530, 1452, 1276 cmÀ1 1H NMR
;
(CDCl3, 200 MHz): d 7.36–7.28 (5H, m), 5.73 (1H, m),
5.10–5.01 (4H, m), 4.43 (1H, d, J = 8.0 Hz), 3.68 (1H,
m), 2.28–2.10 (2H, m), 1.39–1.20 (8H, m), 0.88 (3H, t,
J = 7.0 Hz); 13C NMR (CDCl3, 50 MHz): d 156.2,
136.9, 134.2, 128.6, 128.0, 117.9, 67.0, 50.8, 39.5, 34.6,
31.4, 25.2, 22.6, 14.0; FABMS: m/z 298 [M+Na]+Å;
Anal. Calcd for C17H25NO2: C, 74.18; H, 9.09; N,
5.09. Found: C, 74.26; H, 9.17; N, 5.01.
The spectral and analytical data of the previously
unknown homoallylic amines are given below.
Compound 3b: White solid; mp 62–64 ꢁC; IR (KBr): mmax
3352, 1690, 1526, 1457, 1259 cmÀ1; H NMR (CDCl3,
1
Acknowledgments
200 MHz): d 7.36–7.23 (5H, m), 7.15–7.07 (4H, m),
5.63 (1H, m), 5.12–4.92 (5H, m), 5.71 (1H, br s), 2.59–
2.48 (2H, m), 2.32 (3H, s); 13C NMR (CDCl3,
50 MHz): d 156.2, 137.1, 136.8, 134.4, 129.2, 128.6,
128.0, 126.1, 118.8, 100.0, 67.5, 54.5, 40.8, 21.2; FABMS:
m/z 318 [M+Na]+Å; Anal. Calcd for C19H21NO2:
C, 77.29; H, 7.12; N, 4.75. Found: C, 77.38; H, 7.04; N,
4.86.
The authors thank CSIR and UGC, New Delhi, for
financial assistance.
References and notes
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Compound 3e: White solid; mp 68–70 ꢁC; IR (KBr):
mmax 3348, 1703, 1593, 1507, 1238 cmÀ1 1H NMR
;
(CDCl3, 200 MHz): d 7.40–7.22 (5H, m), 6.47–6.39
(2H, m), 5.65 (1H, m), 5.18–4.97 (5H, m), 4.66 (1H, br
s), 3.82 (6H, s), 3.81 (3H, s), 2.58–2.47 (2H, m); 13C
NMR (CDCl3, 50 MHz): d 156.9, 155.9, 153.4, 138.0,
137.2, 136.5, 133.9, 128.6, 128.3, 118.6, 105.6, 103.3,
67.0, 60.9, 56.2, 54.9, 41.3; FABMS: m/z 394
[M+Na]+Å; Anal. Calcd for C21H25NO5: C, 67.93; H,
6.74; N, 3.77. Found: C, 67.81; H, 6.80; N, 3.69.
Compound 3i: Oil; IR (KBr): mmax 3324, 1701, 1604,
1
1521, 1348 cmÀ1; H NMR (CDCl3, 200 MHz): d 8.15
(2H, d, J = 8.0 Hz), 7.41 (2H, d, J = 8.0 Hz), 7.38–7.23
(5H, m), 5.61 (1H, m), 5.19–5.01 (5H, m), 4.82 (1H,
br s), 2.57–2.43 (2H, m); 13C NMR (CDCl3, 50 MHz):
d 156.1, 150.0, 147.2, 136.2, 132.5, 128.7, 128.5, 128.0,
127.2, 123.9, 119.8, 67.0, 54.1, 40.8; FABMS: m/z
349 [M+Na]+Å; Anal. Calcd for C18H18N2O4: C,
66.26; H, 5.52; N, 8.59. Found: C, 66.37; H, 5.48; N,
8.65.
6. Ollevier, T.; Li, Z. Org. Biomol. Chem. 2006, 4, 4440–
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