Molecules 2007, 12
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the residue was purified by column chromatography (24 x 400 mm, 30 g of silica gel, eluent: 10%
diethyl ether in hexane) to give 3.69 g (96%) of 7a. MS (m/e): 126, 111, 98, 84, 69 (100%), 56, 41; 1H-
NMR (300 MHz) δ: 0.86-0.90 (m, 6H), 1.09-1.42 (m, 13H), 1.52-1.61 (m, 2H), 1.80 (s, br, 1H), 3.63
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(t, J = 6.6 Hz, 2H); C-NMR (75 MHz) δ: 14.19, 19.72, 22.82, 27.15, 29.81, 30.40, 32.08, 32.79,
33.15, 37.16, 63.20.
4-Methyl-1-undecanol (7b): In the same manner as described above for the preparation of 7a, we
obtained 2.74 g (97%) of 7b from 2.80 g of the aldehyde 6b. MS (m/e): 140, 125, 112, 97, 84, 69
1
(100%), 56, 41; H-NMR (300 MHz) δ: 0.86-0.90 (m, 6H), 1.11-1.40 (m, 15H), 1.52-1.63 (m, 2H),
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1.78 (s, br, 1H), 3.62 (t, J = 6.6 Hz, 2H); C-NMR (75 MHz) δ: 14.12, 19.65, 22.71, 27.07, 29.40,
29.99, 30.36, 31.94, 32.65, 32.97, 37.01, 63.45.
4-Methyl-1-decanyl 4-methylbenzenesulfonate (8a) and 4-methyl-1-undecanyl 4-methylbenzene-
sulfonate (8b): The tosylates 8a and 8b were prepared following the general procedure described
above for the preparation of the tosylate 4. We obtained 6.29 g (92%) of 8a from 3.61 g of 7a. Data of
8a: MS (m/e): 207 (10), 173 (74), 154 (39), 126 (49), 111 (34), 97 (36), 91 (100), 84 (46), 69 (91), 56
(65), 41 (61);1H-NMR: (300 MHz) δ: 0.80 (d, J = 6.6 Hz, 3H), 0.86-0.90 (m, 3H), 1.01-1.35 (m, 13H),
1.56-1.72 (m, 2H), 2.45 (s, 3H), 4.01 (t, J = 6.6 Hz, 2H), 7.36 (d, J = 8.4 Hz, 2H), 7.79 (d, J = 8.4 Hz,
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2H); C-NMR: (75 MHz) δ: 14.12, 19.41, 21.63, 22.68, 26.48, 26.90, 29.60, 31.91, 32.28, 32.49,
36.78, 71.12, 127.90 (2C), 129.80 (2C), 133.33, 144.62. Analogously, 4.49 g (91%) of 8b was
obtained from 2.70 g of 7b. Data of 8b: MS (m/e): 207 (3), 173 (100), 155, 140, 125, 111, 91, 83, 69,
1
56, 43, 41; H-NMR: (300 MHz) δ: 0.80 (d, J = 6.3 Hz, 3H), 0.88 (t, J = 6.6 Hz, 3H), 1.07-1.32 (m,
15H), 1.56-1.72 (m, 2H), 2.45 (s, 3H), 4.01 (t, J = 6.6 Hz, 2H), 7.34 (d, J = 8.3 Hz, 2H), 7.79 (d, J =
13
8.3 Hz, 2H); C-NMR: (75 MHz) δ: 14.06, 19.35, 21.58, 22.69, 26.48, 26.95, 29.35, 29.90, 31.91,
32.27, 32.49, 36.77, 71.11, 127.88 (2C), 129.79 (2C), 133.31, 144.60.
5,9-Dimethylpentadecane (1): 2-Hexylmagnesium bromide was prepared by reaction of 4.80 g (29
mmol) of 2-bromohexane [14] with magnesium turnings (0.77 g, 32 mmol) in dried diethyl ether (30
mL) for 2 hours. In the same manner as described for the preparation of the alkene 5a (see general
procedure above), we obtained 1, albeit together with a very small amount of 5,6-dimethyldecane.
After removal of 5,6-dimethyldecane by vacuum distillation (65-68 oC/6 mbar), 2.15 g (93%) of pure 1
could be isolated (from 3.10 g (9.5 mmol) of (8a). MS (m/e): 240 (M+, 5), 225 (4), 211 (2), 197 (1),
1
183 (21), 155 (32), 127 (10), 112 (35), 99 (22), 85 (77), 71 (93), 57 (100), 43 (58); H-NMR: (600
MHz) δ: 0.84 (t, J = 6.6 Hz, 3H), 0.84 (t, J = 6.6 Hz, 3H) [15], 0.87-0.90 (m, 6H), 1.02-1.11 (m, 4H),
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1.16-1.32 (m, 18H), 1.33-1.39 (m, 2H); C-NMR: (150 MHz) δ: 14.14, 14.19, 19.72, 19.78, 22.73,
23.09, 24.50, 27.09 (27.10) [16], 29.38 (29.40) [16], 29.74, 32.01, 32.77 (32.79) [16], 32.80 (32.82)
[16], 36.79 (36.89) [16], 37.12 (37.21) [16], 37.43, 37.48.
5,9-Dimethylhexadecane (2): In the same manner as described above for the preparation of 1, 1.43
g (91%) of 2 was obtained from 2.10 g (6.5 mmol) of 8b. MS (m/e): 254 (M+, 5), 239 (5), 211 (2), 197
(31), 169 (10), 155 (35), 126 (37), 99 (22), 85 (97), 71 (90), 57 (100), 43 (76); 1H-NMR: (300 MHz) δ:
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0.84 (d, J = 6.6 Hz, 6H), 0.87-0.91 (m, 6H), 1.02-1.11 (m, 4H), 1.16-1.39 (m, 22H); C-NMR: (75