Cyclohexenecarbaldehydes
FULL PAPER
2,4-Dimethyl-1-(prop-1-en-2-yl)cyclohex-3-enecarbaldehyde (6c): This
compound was purified by distillation under reduced pressure to yield a
colorless liquid (260 g, 62%). Odor description: floral, woody, earthy.
B.p. 62–658C/0.15 mbar; 1H NMR (300 MHz, CDCl3): d=9.40 (s, 1H),
5.35–5.32 (m, 1H), 5.15 (s, 1H), 4.89 (s, 1H), 2.75–2.63 (m, 1H), 2.07–
1.70 (m, 4H), 1.70 (s, 3H), 1.60 (s, 3H), 1.00 ppm (d, J=7.1 Hz); 13C
NMR (75 MHz, CDCl3): d=202.8 (d; CHO), 141.8 (s; CH2=CCH3), 133.5
(s; 4-C), 124.9 (d; 3-C), 116.0 (t; CH2=CCH3), 57.6 (s; 1-C), 32.0 (d; 2-C),
27.2 (t; 5-C), 23.2 (q; 4-CH3), 22.8 (t; 6-C), 20.0 (q; CH2=CCH3),
17.3 ppm (q; 2-CH3); IR (neat): n˜ =2966, 2693, 1721, 1636, 1447, 1378,
900 cmÀ1; GC/MS (EI): m/z (%): 178 [M]+ (54), 163 (28), 149 (74), 136
(35), 121 (58), 107 (60), 91 (53), 82 (100), 67 (84), 55 (15), 41 (33);
HRMS (EI): m/z: calcd for C12H18O: 178.1358; found: 178.1372.
J=7.5, 7.5, 7.5 Hz, 1H; 7a-H), 2.72–2.62 (m, 2H; 4-Ha, 7-Ha), 2.27–2.17
(dddd, J=16.6, 6.1, 4.5, 1.5 Hz, 1H; 4-Hb), 1.91 (dd, J=15.5, 8.3 Hz, 1H;
7-Hb), 1.79 (s, 3H; (CH3)a), 1.74 ppm (s, H, CH3)b); 13C NMR (75 MHz,
CDCl3): d=192.1 (d; CHO), 151.8 (d; C-5), 143.7 (s, C-6), 142.9 (s, C-1),
136.7 (d; C-3), 131.4 (d; C-2), 122.6 (s, C(CH3)2), 43.4 (d; C-3a), 39.4 (d;
N
C-7a), 29.3 (t, C-4), 23.8 (t, C-7), 21.1 (q, (CH3)a), 21.0 ppm (q, (CH3)b);
IR (neat): n˜ =2910, 2716, 1681, 1443, 1374 cmÀ1; GC/MS (EI): m/z (%):
188 [M]+ (30), 173 (4), 159 (2), 145 (5), 128 (6), 115 (7), 106 (100), 91
(40), 77 (7), 65 (6), 53 (4), 39 (5); HRMS (EI): m/z: calcd for C13H16O:
188.1201; found: 188.1199.
5-Methyl-3a,4,7,7a-tetrahydro-1H-indene-6-carbaldehyde (7i): This com-
pound was purified by distillation under reduced pressure to yield a yel-
lowish liquid (134 g, 35%). Odor description: green, fruity, melon.
1H NMR (400 MHz, C6D6): d=10.07 (s, 1H), 5.51–5.49 (m, 1H), 5.29–
5.25 (m, 1H), 2.71–2.64 (m, 1H), 2.44–2.18 (m, 4H), 1.88–1.78 (m, 2H),
1.62 (s, 3H), 1.61–1.45 ppm (m, 1H); 13C NMR (100 MHz, C6D6): d=
187.3 (d), 157.1 (s), 134.9 (s), 133.3 (d), 130.8 (d), 44.2 (d), 40.0 (t), 37.1
(t), 34.5 (d), 25.7 (t), 18.0 ppm (q); GC/MS (EI): m/z (%): 162 [M]+ (46),
147 (22), 131 (10), 115 (6), 105 (9), 91 (20), 77 (14), 66 (100), 51 (6), 39
(12); IR (neat): n˜ =3048, 2925, 2848, 1665, 1632, 1434, 1377 cmÀ1; HRMS
(EI): m/z: calcd for C11H14O: 162.1045; found: 162.1041.
1-(But-1-enyl)-2,4-dimethylcyclohex-3-enecarbaldehyde (6d): This com-
pound was purified by distillation under reduced pressure to yield a col-
orless liquid (322 g, 71%). Odor description: fruity, apple-like, floral.
Four isomers in a ratio of 5:2:7:1. B.p. 112–1158C/0.12 mbar. 1H NMR
(300 MHz, CDCl3): d=9.62, 9.53, 9.45, 9.36 (4s, 1H), 5.60–5.14 (m, 3H),
2.63–2.33 (m, 1H), 2.13–1.61 (m, 9H), 1.01–0.90 ppm (m, 6H); 13C NMR
(75 MHz, CDCl3): major isomer: d=203.3 (d), 137.3 (d), 134.6 (s), 129.0
(d), 124.1 (d), 53.3 (s), 36.6 (d), 27.3 (t), 27.1 (t), 23.3 (q), 22.7 (t), 17.2
(q), 14.1 ppm (q); IR (neat): n˜ =1964, 2874, 2711, 1721, 1451 cmÀ1; GC/
MS (EI): m/z (%): 192 [M]+ (20), 163 (20), 135 (13), 121 (16), 107 (35),
93 (24), 82 (100), 67 (46), 55 (18), 41 (20); HRMS (EI): m/z: calcd for
C13H20O: 192.1514; found: 192.1526.
4-Ethyl-3a,4,7,7a-tetrahydro-1H-indene-6-carbaldehyde (7j): This com-
pound was purified by distillation under reduced pressure to yield a yel-
lowish liquid 177 g (42%). Odor description: green, fruity, weak.
1H NMR (300 MHz, CDCl3): d=9.42, 9.40 (2s, 1H), 6.84–6.83, 6.74–6.72
(2m, 1H), 5.74–5.53 (m, 2H), 3.26–3.13 (m, 1H), 2.87–2.75 (m, 1H),
2.66–1.46 (m, 7H), 1.06, 1.02 ppm (2t, J=7.5 Hz, 3H); major isomer: 13C
NMR (75 MHz, CDCl3): d=192.7 (d), 157.3 (d), 142.4 (s), 132.5 (d),
130.3 (d), 49.1 (d), 41.2 (d), 41.0 (t), 34.4 (d), 25.1 (t), 24.9 (t), 12.44 ppm
(q); GC/MS (EI): m/z (%): 176 [M]+ (28), 147 (23), 117 (13), 105 (8), 91
(21), 77 (14), 66 (100), 41 (10); minor isomer: 13C NMR (75 MHz,
CDCl3): d=192.7 (d), 156.3 (d), 142.5 (s), 133.9 (d), 130.2 (d), 49.4 (d),
41.9 (d), 39.4 (t), 35.5 (d), 27.1 (t), 24.7 (t), 11.63 ppm (q); IR (neat): n˜ =
3054, 2961, 2929, 1683, 1447 cmÀ1; HRMS (EI): m/z: calcd for C12H16O:
176.1201; found: 176.1198.
2,4-Dimethyl-1-(2-methylprop-1-enyl)cyclohex-3-enecarbaldehyde (6e):
This compound was purified by distillation under reduced pressure to
yield a colorless liquid (235 g, 52%). Odor description: fruity, apple,
rose-petal, watery. B.p. 88–928C/0.12 mbar; 1H NMR (300 MHz, CDCl3):
d=9.42 (s, 1H), 5.29–5.27 (m, 1H), 4.95 (s, 1H), 2.34–2.24 (m, 1H), 1.90–
1.70 (m, 4H), 1.71 (s, 3H), 1.61 (s, 3H), 1.49 (s, 3H), 0.85 ppm (d, J=
7.1 Hz, 3H); 13C NMR (75 MHz, CDCl3): d=203.3 (d), 137.6 (s), 134.6
(s), 124.8 (d), 124.1 (d), 52.9 (s), 36.9 (d), 27.4 (t), 27.1 (q), 23.3 (q), 21.9
(t), 18.6 (q), 17.3 ppm (q); IR (neat): n˜ =2912, 2712, 1721, 1449, 1378,
821 cmÀ1; GC/MS (EI): m/z (%): 192 [M]+ (63), 177 (21), 163 (31), 135
(19), 121 (27), 107 (69), 95 (35), 82 (100), 67 (46), 55 (14), 41 (23);
HRMS (EI): m/z: calcd for C13H20O: 192.1514; found: 192.1508.
1-Vinylcyclohex-3-enecarbaldehyde (6k): This compound was purified by
column chromatography to yield a colorless liquid. Odor description of
the mixture: green, fruity, apple, melon, floral, violet. 1H NMR
(300 MHz, CDCl3): d=9.37 (s, 1H), 5.77–5.63 (m, 3H), 5.29 (d, J=
10.6 Hz, 1H), 5.16 (d, J=17.7 Hz, 1H), 2.53–1.67 ppm (m, 6H); 13C
NMR (75 MHz, CDCl3): d=201.8 (d), 137.9 (d), 127.1 (d), 123.9 (d),
117.0 (t), 51.7 (s), 29.4 (t), 26.9 (t), 22.0 ppm (t); IR (neat): n˜ =3027,
2921, 2840, 1725, 1439, 922, 717, 665 cmÀ1; GC/MS (EI): m/z (%): 136
[M]+ (5), 118 (17), 107 (28), 91 (46), 79 (100), 67 (9), 53 (14), 39 (23);
HRMS (EI): m/z: calcd for C9H12O: 136.0888; found: 136.0880.
1-(Buta-1,3-dienyl)-2,4-dimethylcyclohex-3-enecarbaldehyde (6 f): This
compound was purified by column chromatography to yield a yellowish
liquid (188 g, 42%). Odor description: fruity, apple, mild floral. Four iso-
mers in a ratio of 9:5:2:1. 1H NMR (300 MHz, CDCl3): d=9.62, 9.52,
9.48, 9.39 (4s, 1H), 6.44–6.01 (m, 2H), 5.63–5.05 (m, 4H), 2.62–2.40 (m,
1H), 1.95–1.60 (m, 7H), 0.99, 0.98, 0.92, 0.91 ppm (4d, J=7.1 Hz, 3H);
major isomer: 13C NMR (75 MHz, CDCl3): d=202.1 (d), 136.7 (d), 134.1
(s), 134.0 (d), 133.3 (d), 124.6 (d), 117.4 (t), 53.6 (s), 35.2 (d), 27.1 (t),
25.0 (t), 23.3 (q), 17.16 ppm (q); IR (neat): n˜ =2963, 2710, 1718, 1449,
1378, 1006, 907 cmÀ1; GC/MS (EI): m/z (%): 190 [M]+ (37), 175 (5), 161
(16), 147 (12), 133 (12), 119 (27), 105 (40), 91 (45), 82 (100), 67 (65), 55
(13), 41 (20); HRMS (EI): m/z: calcd for C13H18O: 190.1358; found:
190.1368.
4-Vinylcyclohex-1-enecarbaldehyde (7k): This compound was purified by
column chromatography to yield a colorless liquid. Odor description of
the mixture: green, fruity, apple, melon 1H NMR (300 MHz, CDCl3): d=
9.44 (s, 1H), 6.82–6.80 (m, 1H), 5.81 (ddd, J=17.0, 10.2, 6.6 Hz, 1H),
5.04 (d, J=17.0 Hz, 1H), 4.99 (d, J=10.2 Hz, 1H), 2.55–2.05 (m, 5H),
1.91–1.83 (m, 1H), 1.44–1.30 ppm (m, 1H); 13C NMR (75 MHz, CDCl3):
d=193.9 (d), 149.9 (d), 142.1 (d), 141.3 (s), 113.5 (t), 37.1 (d), 32.0 (t),
27.2 (t), 20.8 ppm (t); IR (neat): n˜ =2928, 1686, 1643, 1420, 1178,
916 cmÀ1; GC/MS (EI): m/z (%): 136 [M]+ (21), 121 (14), 107 (60), 91
(41), 79 (88), 67 (27), 54 (100), 39 (49); HRMS (EI): m/z: calcd for
C9H12O: 136.0888; found: 136.0883.
rac-3a,4,7,7a-Tetrahydro-1H-indene-6-carbaldehyde (7g): This compound
was purified by distillation under reduced pressure to yield a yellowish
liquid (150 g, 43%). Odor description: green, melon, cucumber, apple,
1
marine, floral. B.p. 65–708C/0.054 mbar; H NMR (400 MHz, CDCl3): d=
9.44 (s, 1H), 6.97 (dd, J=4.9, 4.9 Hz, 1H), 5.69–5.56 (m, 2H), 2.99–2.97
(m, 1H), 2.61–2.39 (m, 4H), 2.23–2.19 (m, 1H), 2.09–1.95 ppm (m, 2H);
13C NMR (100 MHz, CDCl3): d=192.6 (d), 152.2 (d), 142.6 (s), 134.8 (d),
130.3 (d), 42.9 (d), 39.8 (t), 34.6 (d), 29.2 (t), 24.2 ppm (t); IR (neat): n˜ =
3050, 2924, 2717, 1678, 1171 cmÀ1; GC/MS (EI): m/z (%): 148 [M]+ (26),
133 (6), 120 (10), 105 (6), 91 (18), 77 (13), 66 (100), 55 (6), 39 (12);
HRMS (EI): m/z: calcd for C10H12O: 148.0888; found: 148.0884.
1-(Prop-1-en-2-yl)cyclohex-3-enecarbaldehyde (6l): This compound was
purified by column chromatography to yield a colorless liquid. Odor de-
scription: fresh, green, camphoraceous, perilla aldehyde-like. 1H NMR
(300 MHz, CDCl3): d=9.23 (s, 1H), 5.72–5.60 (m, 2H), 5.07 (s, 1H), 4.91
(s, 1H), 2.54–2.44 (m, 1H), 2.18–2.71 (m, 5H), 1.68 ppm (s, 3H); 13C
NMR (75 MHz, CDCl3): d=201.4 (d), 143.0 (s), 126.8 (d), 124.4 (d),
114.4 (t), 54.4 (s), 29.0 (t), 25.5 (t), 22.4 (t), 19.5 ppm (q); IR (neat): n˜ =
3028, 2923, 2698, 1725, 1668, 1634, 1440, 1377, 901 cmÀ1; GC/MS (EI):
m/z (%): 150 [M]+ (9), 135 (17), 121 (36), 107 (21), 93 (73), 79 (100), 67
(21), 55 (24), 41 (27); HRMS (EI): m/z: calcd for C10H14O: 150.1045;
found: 150.1041.
rac-1-(Propan-2-ylidene)-3a,4,7,7a-tetrahydro-1H-indene-6-carbaldehyde
(7h): A total of 290 g crude product was obtained. The crude product
(5 g) was purified by column chromatography to yield a yellowish liquid
(3.2 g, 42%). The product easily decomposed at RT. Odor description:
1
fruity, green, woody. H NMR (300 MHz, CDCl3): d=9.44 (s, 1H; CHO),
6.95 (ddd, J=5.9, 4.5, 1.5 Hz, 1H; 5-H), 6.34 (dd, J=5.7, 2.3 Hz, 1H; 2-
H), 5.70 (brd, J=5.7 Hz, 1H; 3-H), 3.24–3.17 (m, 1H; 3a-H), 2.92 (ddd,
Chem. Eur. J. 2008, 14, 5335 – 5345
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