Synthesis of Methyl ω-Alkylaminopentenoates
cis-1-Allyl-3-ben zyloxy-4-[(2-ch lor o-1,1-d im eth yl)eth yl]-
a zetid in -2-on e (7c): H NMR (CDCl3) δ 1.15 and 1.16 (2 ×
11.9 Hz, OCH(H)), 7.32-7.36 (5H, m, C6H5); 13C NMR (CDCl3)
δ 20.75 and 20.79 (Me2CH), 22.70 and 24.76 (Me2Cq), 37.14
(Cq(CH3)2), 44.06 (CH2Br), 47.28 (CHMe2), 63.52 (NCHCq),
73.17 (OCH2C6H5), 81.10 (OCH), 127.65, 127.83 and 128.43
(Co, Cm, Cp), 137.27 (Cq), 168.77 (CdO); IR (NaCl) 1739 cm-1
(CdO); MS m/z no M+, 224/226 (4), 208 (3), 196 (8), 194 (27),
192 (19), 177/179 (8), 175 (6), 114 (8), 105 (49), 99 (100), 98
(13), 91 (49), 88 (90), 86 (17), 84 (29), 83 (11), 81 (9), 69 (15),
67 (12), 59 (25), 56 (16), 55 (27), 53 (8). Flash chromatography
petroleum ether/EtOAc 75/25, Rf 0.35, yield 75%. Anal. Calcd
for C17H24BrNO2: C, 57.63; H, 6.83; N, 3.95. Found: C, 57.75;
H, 6.94; N, 3.79.
1
3H, 2 × s, Me2Cq), 3.44 (1H, d, J ) 10.9 Hz, CH(H)Cl), 3.63
(1H, d × d, J ) 15 Hz, J ) 7 Hz, NCH(H)), 3.76 (1H, d, J )
10.9 Hz, CH(H)Cl), 3.87 (1H, d, J ) 5.3 Hz, NCHCq), 4.19 (1H,
d × d, J ) 15 Hz, J ) 5 Hz, NCH(H)), 4.70 (1H, d, J ) 5.3 Hz,
OCH), 4.70 (1H, d, J ) 11.9 Hz, OCH(H)), 4.95 (1H, d, J )
11.9 Hz, OCH(H)), 5.19-5.25 (2H, m, CHCH2), 5.67-5.80 (1H,
m, CHCH2), 7.26-7.36 (5H, m, C6H5); 13C NMR (CDCl3) δ 21.89
and 23.65 (Me2Cq), 37.86 (Cq(CH3)2), 44.33 (NCH2), 53.12 (CH2-
Cl), 62.89 (NCHCq), 73.12 (OCH2C6H5), 81.89 (OCH), 119.06
(dCH), 127.53, 127.81 and 128.39 (Co, Cm, Cp), 131.55 (dCH2),
137.09 (Cq), 168.55 (CdO); IR (NaCl) 1756 cm-1 (CdO); MS
m/z no M+, 224 (10), 175 (23), 133 (2), 91 (100), 89 (2), 84 (2),
83 (2), 65 (7), 55 (3). Flash chromatography petroleum ether/
cis-3-Ben zyloxy-4-[(2-br om o-1,1-d im eth yl)eth yl]-1-cy-
1
cloh exyla zetid in -2-on e (8b): H NMR (CDCl3) δ 1.20-2.01
(10H, m, (CH2)5), 1.18 and 1.20 (2 × 3H, 2 × s, Me2Cq), 3.01-
3.10 (1H, m, NCH), 3.33 (1H, d, J ) 10 Hz, CH(H)Br), 3.73
(1H, d, J ) 10 Hz, CH(H)Br), 3.85 (1H, d, J ) 5.3 Hz, NCHCq),
4.57 (1H, d, J ) 5.3 Hz, OCH), 4.67 (1H, d, J ) 11.9 Hz,
OCH(H)), 4.92 (1H, d, J ) 11.9 Hz, OCH(H)), 7.26-7.34 (5H,
m, C6H5); 13C NMR (CDCl3) δ 22.68 and 24.69 (Me2Cq), 25.18,
25.23, 25.73, 30.64 and 31.00 ((CH2)5), 37.18 (Cq(CH3)2), 44.06
(CH2Br), 55.36 (NCH), 63.27 (NCHCq), 73.04 (OCH2C6H5),
80.86 (OCH), 127.53, 127.74 and 128.34 (Co, Cm, Cp), 137.19
(Cq), 168.51 (CdO); IR (NaCl) 1737 cm-1 (CdO); MS m/z no
M+, 267/269 (58), 176 (100), 134 (14), 99 (12), 92 (50), 91 (89),
86 (13), 84 (18), 83 (48), 65 (27), 55 (36). Flash chromatography
petroleum ether/EtOAc 8/2, Rf 0.38, yield 99%. Anal. Calcd for
EtOAc 75/25, Rf 0.29, yield 97%. Anal. Calcd for C17H22
-
ClNO2: C, 66.33; H, 7.20; N, 4.55. Found: C, 66.45; H, 7.33;
N, 4.44.
cis-1-Allyl-4-[(2-ch lor o-1,1-d im et h yl)et h yl]-3-p h en yl-
oxya zetid in -2-on e (7d ): 1H NMR (CDCl3) δ 1.21 and 1.23 (2
× 3H, 2 × s, Me2Cq), 3.51 (1H, d, J ) 10.9 Hz, CH(H)Cl), 3.71
(1H, d × d, J ) 16 Hz, J ) 7 Hz, NCH(H)), 3.75 (1H, d, J )
10.9 Hz, CH(H)Cl), 4.08 (1H, d, J ) 5.3 Hz, NCHCq), 4.24 (1H,
d × d, J ) 16 Hz, J ) 6 Hz, NCH(H)), 5.25 (1H, d, J ) 5.3 Hz,
OCH), 5.25-5.30 (2H, m, CHCH2), 5.72-5.87 (1H, m, CHCH2),
7.00-7.45 (5H, m, C6H5); 13C NMR (CDCl3) δ 21.98 and 23.63
(Me2Cq), 38.13 (Cq(CH3)2), 44.89 (NCH2), 53.23 (CH2Cl), 63.11
(NCHCq), 81.42 (OCH), 119.57 (dCH), 115.99, 122.51, 129.49
and 129.63 (Co, Cm, Cp), 131.32 (dCH2), 157.72 (Cq), 167.33
(CdO); IR (NaCl) 1742 cm-1 (CdO); MS m/z no M+, 209/211
(23), 158 (2), 145 (2), 160 (100), 112 (2), 108 (3), 107 (9), 105
(3), 99 (3), 94 (17), 91 (7), 79 (4), 78 (3), 77 (16), 67 (3), 66 (6),
65 (8), 55 (7). Flash chromatography petroleum ether/EtOAc
75/25, Rf 0.29, yield 97%. Anal. Calcd for C16H20ClNO2: C,
65.41; H, 6.86; N, 4.77. Found: C, 65.54; H, 6.94; N, 4.65.
cis-4-[(2-Ch lor o-1,1-dim eth yl)eth yl]-1-isopr opyl-3-m eth -
oxya zetid in -2-on e (7e): 1H NMR (CDCl3) δ 1.13 and 1.16 (2
× 3H, 2 × s, Me2Cq), 1.29 and 1.45 (2 × 3H, 2 × d, J ) 6.6 Hz,
Me2CH), 3.44 (1H, d, J ) 10.9 Hz, CH(H)Cl), 3.51 (1H, septet,
J ) 6.6 Hz, CHMe2), 3.55 (3H, s, OMe), 3.73 (1H, d, J ) 10.9
Hz, CH(H)Cl), 3.84 (1H, d, J ) 5.3 Hz, NCHCq), 4.40 (1H, d,
J ) 5.3 Hz, OCH); 13C NMR (CDCl3) δ 20.72 (Me2CH), 21.89
and 23.65 (Me2Cq), 37.93 (Cq(CH3)2), 47.13 (CHMe2), 53.40
(CH2Cl), 59.44 (OMe), 62.96 (NCHCq), 83.54 (OCH), 168.80
(CdO); IR (NaCl) 1751 cm-1 (CdO); MS m/z 233/235 (0.1, M+),
198 (0.2, M+ - Cl), 163 (2), 149 (11), 133 (3), 124 (1), 114 (2),
99 (100), 98 (2), 84 (1), 83 (4), 72 (1), 70 (2), 67 (3), 56 (1), 55
(4), 53 (1). Flash chromatography petroleum ether/EtOAc 75/
25, Rf 0.30, yield 73%. Anal. Calcd for C11H20ClNO2: C, 56.52;
H, 8.52; N, 5.99. Found: C, 56.38; H, 8.63; N, 5.77.
C
20H28BrNO2: C, 60.91; H, 7.16; N, 3.55. Found: C, 60.75; H,
6.94; N, 3.59.
cis-1-Allyl-3-ben zyloxy-4-[(2-br om o-1,1-d im eth yl)eth yl]-
a zetid in -2-on e (8c): 1H NMR (CDCl3) δ 1.17 (2 × 3H, 2 × s,
Me2Cq), 3.33 (1H, d, J ) 10.9 Hz, CH(H)Br), 3.66 (1H, d × d,
J ) 15 Hz, J ) 7 Hz, NCH(H)), 3.71 (1H, d, J ) 10.9 Hz, CH-
(H)Br), 3.87 (1H, d, J ) 5.3 Hz, NCHCq), 4.19 (1H, d × d, J )
15 Hz, J ) 3 Hz, NCH(H)), 4.69 (1H, d, J ) 5.3 Hz, OCH),
4.69 (1H, d, J ) 11.9 Hz, OCH(H)), 4.95 (1H, d, J ) 11.9 Hz,
OCH(H)), 5.18-5.25 (2H, m, CHCH2), 5.67-5.79 (1H, m,
CHCH2), 7.30-7.35 (5H, m, C6H5); 13C NMR (CDCl3) δ 22.70
and 24.78 (Me2Cq), 37.23 (Cq(CH3)2), 43.65 (CH2Br), 44.47
(NCH2), 63.67 (NCHCq), 73.30 (OCH2C6H5), 81.99 (OCH),
119.23 (dCH), 127.67, 127.90 and 128.46 (Co, Cm, Cp), 131.61
(dCH2), 137.10 (Cq), 168.73 (CdO); IR (NaCl) 1751 cm-1 (Cd
O); MS m/z 351/353 (0.1, M+), 267/269 (21), 261 (10), 175 (56),
133 (8), 115 (5), 103 (11), 92 (42), 91 (100), 83 (14), 77 (8), 68
(8), 65 (30), 56 (11), 55 (15), 51 (14), 49 (13). Flash chroma-
tography petroleum ether/EtOAc 75/25, Rf 0.31, yield 90%.
Anal. Calcd for C17H22BrNO2: C, 57.96; H, 6.29; N, 3.98.
Found: C, 57.75; H, 6.42; N, 3.87.
cis-3-Ben zyloxy-4-[(2-br om o-1,1-d im eth yl)eth yl]-1-eth -
yla zetid in -2-on e (8d ): 1H NMR (CDCl3) δ 1.18 (3H, t, J )
7.3 Hz, CH3CH2), 1.18 and 1.20 (2 × 3H, 2 × s, Me2Cq), 2.95-
3.09 (1H, m, CH3CH(H)), 3.33 (1H, d, J ) 10.2 Hz, CH(H)Br),
3.59-3.73 (1H, m, CH3CH(H)), 3.73 (1H, d, J ) 10.2 Hz, CH-
(H)Br), 3.89 (1H, d, J ) 5.3 Hz, NCHCq), 4.65 (1H, d, J ) 11.9
Hz, OCH(H)), 4.67 (1H, d, J ) 5.3 Hz, OCH), 4.94 (1H, d, J )
11.9 Hz, OCH(H)), 7.26-7.36 (5H, m, C6H5); 13C NMR (CDCl3)
δ 12.65 (CH3CH2), 22.55 and 24.76 (Me2Cq), 36.46 (CH3CH2),
37.27 (Cq(CH3)2), 43.65 (CH2Br), 62.80 (NCHCq), 73.22 (OCH2-
C6H5), 81.72 (OCH), 127.62, 127.85 and 128.43 (Co, Cm, Cp),
137.12 (Cq), 168.66 (CdO); IR (NaCl) 1753 cm-1 (CdO); MS
m/z no M+, 268/270 (31), 194/196 (5), 177 (100), 135 (13), 115
(13), 108 (30), 99 (11), 93 (56), 92 (92), 90 (12), 84 (25), 65 (40),
57 (29), 56 (22). Flash chromatography petroleum ether/EtOAc
8/2, Rf 0.15, yield 75%. Anal. Calcd for C16H22BrNO2: C, 56.48;
H, 6.52; N, 4.12. Found: C, 56.60; H, 6.66; N, 4.03.
cis-1-Allyl-4-[(2-ch lor o-1,1-d im e t h yl)e t h yl]-3-m e t h -
1
oxya zetid in -2-on e (7f): H NMR (CDCl3) δ 1.11 and 1.13 (2
× 3H, 2 × s, Me2Cq), 3.44 (1H, d, J ) 10.9 Hz, CH(H)Cl), 3.57
(3H, s, OMe), 3.60 (1H, m, NCH(H)), 3.71 (1H, d, J ) 10.9 Hz,
CH(H)Cl), 3.86 (1H, d, J ) 5.3 Hz, NCHCq), 4.20 (1H, m, NCH-
(H)), 4.51 (1H, d, J ) 5.3 Hz, OCH), 5.19-5.26 (2H, m,
CHCH2), 5.70-5.80 (1H, m, CHCH2); 13C NMR (CDCl3) δ 21.94
and 23.68 (Me2Cq), 38.04 (Cq(CH3)2), 44.42 (NCH2), 53.14 (CH2-
Cl), 59.57 (OMe), 63.16 (NCHCq), 84.53 (OCH), 119.15 (dCH),
131.61 (dCH2), 168.75 (CdO); IR (NaCl) 1738 cm-1 (CdO);
MS m/z 231/233 (0.03, M+), 148/150 (7), 133/135 (2), 99 (100),
91 (2), 85 (3), 84 (2), 83 (3), 71 (2), 69 (3), 67 (6), 65 (3), 56 (3),
55 (11), 53 (4). Flash chromatography petroleum ether/EtOAc
75/25, Rf 0.24, yield 68%. Anal. Calcd for C11H18ClNO2: C,
57.02; H, 7.83; N, 6.04. Found: C, 57.26; H, 7.94; N, 6.16.
cis-3-Ben zyloxy-4-[(2-br om o-1,1-d im eth yl)eth yl]-1-iso-
p r op yla zetid in -2-on e (8a ): 1H NMR (CDCl3) δ 1.19 and 1.21
(2 × 3H, 2 × s, Me2Cq), 1.28 and 1.46 (2 × 3H, 2 × d, J ) 6.6
Hz, Me2CH), 3.34 (1H, d, J ) 10.9 Hz, CH(H)Br), 3.51 (1H,
septet, J ) 6.6 Hz, CHMe2), 3.74 (1H, d, J ) 10.9 Hz, CH(H)-
Br), 3.85 (1H, d, J ) 5.3 Hz, NCHCq), 4.59 (1H, d, J ) 5.3 Hz,
OCH), 4.69 (1H, d, J ) 11.9 Hz, OCH(H)), 4.94 (1H, d, J )
cis-3-Ben zyloxy-4-[(2-b r om o-1,1-d im et h yl)et h yl]-1-n -
p r op yla zetid in -2-on e (8e): H NMR (CDCl3) δ 0.90 (3H, t,
J ) 7.3 Hz, CH3CH2), 1.19 and 1.20 (2 × 3H, 2 × s, Me2Cq),
1.49-1.70 (2H, m, CH2CH3), 2.90-3.00 (1H, m, NCH(H)), 3.33
(1H, d, J ) 10 Hz, CH(H)Br), 3.50-3.61 (1H, m, NCH(H)),
3.73 (1H, d, J ) 10 Hz, CH(H)Br), 3.87 (1H, d, J ) 5.3 Hz,
NCHCq), 4.69 (1H, d, J ) 11.9 Hz, OCH(H)), 4.69 (1H, d, J )
1
J . Org. Chem, Vol. 69, No. 18, 2004 5981