J. B. Sweeney et al. / Tetrahedron 58 (2002) 10113–10126
10123
The combined extracts were dried (MgSO ) and the solvent
4
layer was separated and the aqueous layer was further
extracted with ether (4£20 mL). The combined extracts
removed in vacuo yielding a yellow oil which was purified
by column chromatography, eluting with 1:2 ether/petrol to
give an inseparable 4:1 mixture of cis- and trans-N-methyl-
were dried (MgSO ) and the solvent removed in vacuo
4
yielding a yellow oil which was purified by column
chromatography, eluting with 1:2 ether/petrol to give cis-
N-methyl-2-methoxycarbonyl-2-(p-methoxyphenyl)-3-ethenyl-
pyrrolidine (111 mg, 28%), and methyl-3-aza-2-(p-methoxy-
phenyl)-3-methyl-octa-5,7-dienoate (98 mg, 25%) both as
colourless oils.
2
-methoxycarbonyl-2-(1-naphthyl)-3-ethenylpyrrolidine
35 mg, 89%) as a colourless oil R 0.44 (ether/petrol 1:2);
(
Data for the trans-isomer is indicated by the symbol p . n
f
max
2
1
(
cm ) 2947, 2841, 1718, 1677, 1656, 1639, 734; d
H
p
(
(
CDCl ) 1.71 (1H, dddd, J¼13.4, 3.6, 7.9, 8.8 Hz) , 2.13
3
p
8H, m), 2.25 (12H, s), 2.36 (3H, s) , 2.43 (1H, m) , 2.69
p
p
(
1H, m) , 2.81 (4H, m), 2.88 (4H, ddd, J¼8.8, 9.2, 9.2 Hz),
cis-N-Methyl-2-methoxycarbonyl-2-(p-methoxyphenyl)-3-
21
p
p
3
3
9
.30 (1H, m) , 3.35 (4H, m), 3.46 (3H, s) , 3.53 (12H, s),
ethenylpyrrolidine. R 0.44 (ether/petrol 1:2); n
f
(cm
max
)
p
.83 (1H, ddd, J¼5.5, 9.5, 9.5 Hz) , 4.15 (1H, dd, J¼1.8,
2957, 2851, 1736, 1641 br.; d (CDCl ) 2.08 (2H, m), 2.22
H 3
p
p
.9 Hz) , 4.46 (1H, dd, J¼1.8, 16.8 Hz) , 4.59 (4H, br. d,
(3H, s), 2.64 (1H, ddd, J¼9.5, 9.2, 9.2 Hz), 2.77 (1H, ddd,
J¼9.5, 4.0, 9.2 Hz), 3.25 (1H, ddd, J¼5.9, 8.4, 9.2 Hz), 3.69
(3H, s), 3.79 (3H, s), 4.73 (1H, dd, J¼1.8, 17.2 Hz), 4.98
(1H, dd, J¼1.8, 10.3 Hz), 5.95 (1H, ddd, J¼9.2, 10.3,
17.2 Hz), 6.86 (2H, d, J¼9.2 Hz), 7.26 (2H, d, J¼9.2 Hz);
d (CDCl ) 28.6, 36.4, 50.6, 51.9, 55.2, 57.0, 78.2, 113.0,
J¼16.9 Hz), 4.80 (4H, dd, J¼1.5, 10.3 Hz), 5.03 (1H, ddd,
p
J¼9.5, 9.9, 16.8 Hz) , 6.31 (4H, ddd, J¼8.8, 10.3, 16.9 Hz),
p
.31 (4H, m), 7.25 (1H, m) , 7.32 (4H, m), 7.35 (1H, m) ,
.37 (4H, m), 7.39 (1H, m) , 7.42 (1H, m) , 7.46 (4H, m),
p
6
7
7
7
3
1
1
1
1
2
p
p
p
.56 (1H, m) , 7.72 (1H, m) , 7.76 (4H, m), 7.79 (4H, m),
p
C
3
p
.83 (4H, m), 7.9, (1H, m),) ; d (CDCl ) 29.0, 30.7 , 36.9,
p
117.4, 128.4, 131.6, 137.3, 158.6, 170.7; m/z (CI) 276.1599
(M þH. C H NO requires 276.1600), 216 (100%), 179
C
3
p
p
p
p
p
þ
(45), 148 (8), 96 (4), 67 (21).
7.5 , 50.4, 50.7 , 50.8 , 52.6, 53.4 , 57.0, 76.8 , 77.2,
1
6
22
3
p
13.0 , 117.3, 124.4, 124.5 , 124.7 , 124.8, 124.8, 124.9,
p
p
p
24.9, 125.2, 126.4 , 128.0 , 128.4, 128.7, 128.8 , 131.7,
p
p
p
p
p
p
31.8 , 133.8 , 134.2, 135.1, 136.2 , 138.2, 139.4 , 169.9,
p
Methyl-3-aza-2-(p-methoxyphenyl)-3-methyl-octa-5,7-
21
þ
72.2 ; 296.1657 (MH . C H NO requires 296.1651),
2
dienoate. R 0.36 (ether/petrol 1:2); n
f
(cm ) 2951 and
max
1
9
22
36 (100%), 220 (6).
2837, 1735, 1654 br., 1610; d (CDCl ) 2.25 (3H, s), 3.13
H 3
(
1H, dd, J¼14.1, 6.9 Hz), 3.28 (1H, dd, J¼14.1, 7.3 Hz),
3
.17.12. N-Methyl-N-((methoxycarbonyl)methyl(p-
3.69 (3H, s), 3.80 (3H, s), 4.16 (1H, s), 5.12 (1H, br. d,
J¼9.9 Hz), 5.21 (1H, dd, J¼1.7, 16.8 Hz), 5.54 (1H, ddd,
J¼6.9, 7.3, 10.9 Hz), 6.15 (1H, dd, J¼11.3, 10.9 Hz), 6.52
(1H, ddd, J¼9.9, 11.3, 16.8 Hz), 6.87 (1H, d, J¼8.7 Hz),
7.33 (1H, d, J¼8.7 Hz); d (CDCl ): 39.5, 51.3, 51.9, 55.3,
methoxyphenyl))-3,4-didehydro-piperidinium bromide
6h). Methyl-a-bromo-p-methoxyphenylacetate (2.68 g,
0.3 mmol) was added dropwise over 5 min to a stirred
solution of N-methyl-3,4-didehydropiperidine (1.0 g,
0.3 mmol) in THF (20 mL) under argon. The reaction
(
1
C
3
1
71.7, 113.0, 118.5, 128.2, 128.6, 130.1, 131.8, 132.3, 159.6,
þ
276.1600), 216 (100%), 85 (7), 49 (8).
mixture was heated at reflux for 6 h resulting in the
precipitation of the title compound, which was filtered and
washed with ether (2£25 mL) under argon to give N-methyl-
N-((methoxycarbonyl)methyl(p-methoxyphenyl))-3,4-
didehydropiperidinium bromide (2.91 g, 79%) as a colour-
less deliquescent solid; mp 142.1–142.98C (dichlorometha-
172.5; m/z (CI) 276.1590 (MH . C H NO requires
22
1
6
3
3.17.14. N-Methyl-N-((methoxycarbonyl)methyl-
(p-nitrophenyl))-3,4-didehydro-piperidinium bromide
(6i).
Methyl-a-bromo-p-nitrophenylacetate
(2.82 g,
2
1
ne/petrol); nmax (cm ) (dichloromethane) 2954 and 2838,
10.3 mmol) was added dropwise over 5 min to a stirred
solution of N-methyl-3,4-didehydropiperidine (1.0 g,
10.3 mmol) in THF (20 mL) under argon. The reaction
mixture was heated at reflux for 12 h resulting in the
precipitation of the title compound, which was filtered and
washed with ether (2£25 mL) under argon to give N-methyl-
N-((methoxycarbonyl)methyl(p-nitrophenyl))-3,4-didehydro-
piperidinium bromide (3.11 g, 81%) as a colourless
deliquescent solid; mp 121.9–122.38C (dichloromethane/
1
3
748, 1608, 1583; d (CDCl ) 2.50 (4H, br. m), 3.38 (3H, s),
H 3
.41 (3H, s), 3.77 (6H, s), 3.85 (6H, s), 3.98 (2H, br. m), 4.06
(
2H, br. m), 4.25 (2H, br. m), 4.73 (2H, br. m), 5.71 (2H, br.
m), 6.01 (2H, m), 6.91 (1H, s), 7.00 (4H, d, J¼9.2 Hz), 7.09
(
1H, s), 7.73 (4H, br. m); d (CDCl ) 21.7, 22.0, 43.6, 43.8,
C 3
5
1
4.0, 54.7, 55.6, 56.1, 57.2, 57.3, 74.2, 74.9, 115.5, 115.6,
18.0, 118.1, 119.5, 119.7, 124.8, 125.1, 134.2, 162.5, 168.2;
þ
02 (8%), 179 (82), 151 (16), 137 (7), 121 (20), 98 (100), 82
17).
m/z (CI) 276.1608 (M 2Br. C H NO requires 276.1600),
3
2
(
1
6
22
2
1
petrol); nmax (cm ) (dichloromethane) 3054, 2986, 2957,
2934, 1745, 1699, 1651, 1634, 1605, 1535, 1520 and 1353;
d (CDCl ) 2.55 (4H, br. m), 3.45 (3H, s), 3.54 (3H, s), 3.81
H
3
3
.17.13. cis-N-Methyl-2-methoxycarbonyl-2-(p-methoxy-
phenyl)-3-ethenylpyrrolidine (7h) and methyl-3-aza-2-
p-methoxyphenyl)-3-methyl-octa-5,7-dienoate (8h).
(6 h, s), 4.02 (2H, br. m), 4.19 (2H, br. m), 4.29 (2H, br. m),
4.86 (2H, br. m), 5.76 (2H, br. m), 6.04 (2H, br. m), 7.29
(
(2H, s), 8.17 (4H, br. m), 8.35 (4H, d, J¼8.8 Hz); d
C
Sodium hydride (34 mg, 1.40 mmol) was added to a
suspension of N-methyl-N-((methoxycarbonyl)methyl-
(CDCl ) 21.1, 21.4, 43.3, 54.0, 54.1, 55.1, 55.6, 57.4, 59.0,
3
71.7, 72.7, 118.6, 118.8, 124.4, 124.5, 125.7, 133.0, 133.7,
150.0, 166.7, 166.8; m/z (CI) 291.1352 (M 2Br.
þ
C H N O requires 291.1345), 231 (66%), 185 (9), 153
(27), 136 (35), 98 (100), 96 (36).
(
(
p-methoxyphenyl))-3,4-didehydropiperidinium bromide
500 mg, 1.40 mmol) in DME (20 mL), vigorously stirred
1
5 19 2 4
under argon. The reaction mixture was heated at reflux for
6 h, after which it was cooled and excess base quenched by
1
careful addition of methanol. The mixture was concentrated
in vacuo yielding a solid product, which was partitioned
between water (20 mL) and ether (20 mL). The organic
3.17.15. cis-N-Methyl-2-methoxycarbonyl-2-(p-nitro-
phenyl)-3-ethenylpyrrolidine (7i). Sodium hydride
(32.3 mg, 1.35 mmol) was added to a suspension of