heterocycles and thus further extend the range of aggregative
activation in organic synthesis.
2-(2-Pyridyl)butan-2-ol 2k.18 δH 0.70 (t, 3 H, J 7.5, CH3), 1.45
(s, 3 H, CH3C), 1.85 (q, 2 H, J 7.5, CH2), 4.50 (s, 1 H, OH), 6.90
(m, 1 H, H-5), 7.35–7.40 (m, 2 H, H-3 ϩ H-4) and 8.40 (d, 1 H,
J 4.8, H-6); m/z (CI) 152 (M ϩ Hϩ), 134, 120, 108, 79, 73 and
57.
Experimental
1-(2-Pyridyl)cyclohexanol 2l.1b δH 1.50–2.00 (m, 10 H, CH2),
4.50 (s, 1 H, OH), 7.15–7.50 (m, 3 H, H-3 ϩ H-5 ϩ H-4) and
8.55 (d, 1 H, J 5, H-6); m/z (CI) 178 (M ϩ Hϩ), 160, 149, 134,
106, 99 and 57.
General methods
1H NMR spectra were recorded on a JEOL PMX60 spec-
trometer at 60 MHz with SiMe4 as internal standard and
CDCl3 as solvent. J Values are given in Hz. GC/MS analysis
(EI and CI) were performed on HP5890 spectrometers using
Macherey-Nagel OPTIMA-5 15 m columns and temperature
programming.
General procedure for metallation of quinoline with
BuLiؒLiDMAE
The above prepared BuLiؒLiDMAE cooled to Ϫ78 ЊC was
treated dropwise with a solution of quinoline (0.26 g, 2 mmol)
in hexane (5 ml). After 30 min, the deep red solution was treated
with an appropriate electrophile (20–40 mmol) added as a solu-
tion in anhydrous diethyl ether (25 ml). After 1 h at Ϫ78 ЊC, the
reaction mixture was treated with 10% aqueous HCl (20 ml)
to hydrolyse it. After work-up, the crude product was purified
on a Chromatotron using AcOEt–hexane as eluents.
2-Trimethylsilylquinoline 7a.13 δH 0.32 (s, 9 H, CH3Si) and
7.44–8.05 (m, 6 H, H-Ar); m/z (CI) 202 (M ϩ Hϩ), 186, 130, 73
and 57.
Materials
BuLi (1.6 solution in hexane) was purchased from Aldrich.
N,N-Dimethylaminoethanol (DMAE) was distilled before use.
Pyridine and quinoline were dried over KOH powder before
use. Hexane, THF and Et2O were distilled and stored over
sodium wire before use. LiBr and CuI were dried at 100 ЊC
under reduced pressure for 24 h and used immediately. Chloro-
trimethylsilane, dimethyl disulfide, ketones, aldehydes, amides
and alkyl halides were commercially available and distilled or
recrystallized before use.
[2-2H]Quinoline 7b.19 As a mixture with quinoline: δH 7.20–
8.10 (m, 6 H, H-Ar); m/z (CI) 131 [(M ϩ 1) ϩ Hϩ] and 57.
2-Ethylquinoline 7c.20 δH 1.25 (t, 3 H, J 7.5, CH3), 2.80 (q,
2 H, J 7.5, CH2) and 7.40–7.85 (m, 6 H, H-Ar); m/z (CI) 158
(M ϩ Hϩ), 143, 130 and 57.
General procedure for metallation of pyridine with
BuLiؒLiDMAE
BuLi (16 mmol, 10 ml) was cooled to 0 ЊC under a nitrogen
atmosphere and a solution of N,N-dimethylaminoethanol (8
mmol, 0.72 g) in anhydrous hexane (10 ml) was added dropwise
to it over 15 min. The mixture was then cooled to Ϫ78 ЊC after
which a solution of pyridine (0.32 g, 4 mmol) in hexane (5 ml)
was also added dropwise to it. After 1 h an orange solution was
obtained and an appropriate electrophile (10–40 mmol) as a
solution in anhydrous THF (25 ml) was added rapidly to it.
After 1 h at Ϫ78 ЊC, the reaction mixture was treated with 10%
aqueous HCl (20 ml) to hydrolyse it. The aqueous layer was
then separated and extracted twice with diethyl ether (20 ml).
The combined extracts were dried (MgSO4) and evaporated,
and the crude product was purified on a Chromatotron using
AcOEt–hexane as eluents.
2-Methylthioquinoline 7d.21 δH 2.70 (s, 3 H, CH3S) and 7.25–
8.10 (m, 6 H, H-Ar); m/z (CI) 176 (M ϩ Hϩ), 143, 130 and 57.
Phenyl(2-quinolyl)methanol 7f.22 Mp 68–72 ЊC (lit.,22
69–71 ЊC); δH 5.80 (s, 1 H, CH), 6.20 (s, 1 H, OH) and 7.25–7.80
(m, 6 H, H-Ar); m/z (CI) 236 (M ϩ Hϩ), 218, 158, 130, 107,
79, 69 and 57.
2-(2-Quinolyl)butan-2-ol 7g.23 δH 0.70 (t, 3 H, J 7.5, CH3),
1.45 (s, 3 H, CH3), 1.85 (q, 2 H, J 7.5, CH2), 4.25 (s, 1 H, OH)
and 7.40–7.80 (m, 6 H, H-Ar); m/z (CI) 202 (M ϩ Hϩ), 184, 172,
130, 73 and 57.
Diphenyl(2-quinolyl)methanol 7h.24 Mp 190–192 ЊC (lit.,24
193–195 ЊC); δH 5.90 (s, 1 H, OH) and 7.20–8.15 (m, 16 H,
H-Ar); m/z (CI) 312 (M ϩ Hϩ), 294, 234, 206, 183 and 128.
2-Methylpyridine 2d, 2-benzylpyridine 2f, pyridine-2-
carbaldehyde 2m, 2-benzoylpyridine 2n, 2-bromopyridine 2g
and 2,2Ј-bipyridine 4 were identical in every respect with com-
mercial samples.
Acknowledgements
We thank the editor for useful corrections.
[2-2H]Pyridine 2a.11 Obtained as a mixture with pyridine;
δH 7.25–7.65 (m, 3 H, H-3 ϩ H-5 ϩ H-4) and 8.60 (d, 1 H, J 5,
H-6); m/z (CI) 81 [(M ϩ 1) ϩ Hϩ] and 57.
References
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2-Trimethylsilylpyridine 2c.13 δH 0.25 (s, 9 H, CH3Si), 7.25–
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2-Hexylpyridine 2e.14 δH 0.95 (t, 3 H, J 8, CH3), 1.35–1.70
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1-(2-Pyridyl)hexan-1-ol 2h.15 δH 0.89 (t, 3 H, J 7, CH3), 1.50–
1.55 (m, 6 H, CH2), 1.95 (t, 2 H, J 7.5, CH2), 3.95 (br s, 1 H,
OH), 4.65 (t, 1 H, J 5.5, CHOH), 7.15–7.60 (m, 3 H, H-3 ϩ H-
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(m, 8 H, H-Ar ϩ Pyr-H-3 ϩ Pyr-H-5 ϩ Pyr-H-4) and 8.65
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1 H, J 5, H-6); m/z (EI) 134 (Mϩ), 120, 106, 93, 78 and 65.
J. Chem. Soc., Perkin Trans. 1, 1997
3599