-
70 °C. An ethereal solution of dialkylzinc reagent (20
dt, J 15.4, 6.7, CH
CH CHdCH), 3.96 (1H, app q, J 6.7, CHOH), 2.00 (2H,
app q, J 7, CH
CHdCH), 1.64-1.30 (5H, m, 2 × CH
OH), and 0.89 (6H, t, J 7, 2 × CH ); CGC (standard
conditions) t [(R+S)-alcohol] 45 min; F NMR analysis
of R and S Mosher esters, δ (CDCl , 282 MHz) -72.0 and
-72.1 (CF ).
2
CHdCH), 5.43 (1H, dd, J 15.3, 6.7,
mmol, prepared according to ref 23) was then added slowly
to the mixture with the development of a strong yellow
colouration. After stirring for approximately 45 min (to
allow the mixture to equilibrate to -78 °C), PhCHO (1.12
mL, 11.1 mmol) was added dropwise and the reaction stirred
at -78 °C for a further 45-60 min. On being allowed to
warm to -30 °C the reaction mixture was stirred for 40-
2
2
2
+
3
1
9
R
F
3
3
(-)-Ethyl-3-methyl-4-hydroxy-2-hexenoate (7): purified
by distillation at 110-130 °C, 0.4 mmHg, to give a
44 h (until completion of the reaction by TLC analysis). The
2
D
1
reaction mixture was then drawn off into the collecting
funnel, and the “tea bag” was washed with diethyl ether (3
colourless oil, the alcohol 7; [R] -1.0 (c 1.57, CHCl
3
)
2
[lit. [R]
D
-10.20 (c 1.47, CHCl
(CDCl , 200 MHz) 5.87-5.85 (1H,
m, alkene CH), 4.11 (2H, q, J 6.7, CH CH OCO), 3.97 (1H,
t, J 6.7 CHOH), 2.35 (1H, s, OH), 2.06 (3H, d, J 1.7, CH ),
1.74-1.40 (2H, m, CHOHCH CH ), 1.24 (3H, t, J 7.2,
CH CH OCO), and 0.87 (3H, t, J 7.2, CHOHCH CH ); CGC
[(S)-alcohol]
3 f
)]; R 0.42 (50% diethyl
×
60 mL) with each wash containing Ti(OCHMe
)
2 4
(1 mL).
ether in pentane); δ
H
3
The combined reaction mixture and washings were quenched
onto 1 M HCl, extracted, and purified by flash column
chromatography to give the pure alcohols for analysis.
Data for Compounds Prepared via “Tea Bag” Meth-
3
2
3
2
3
3
2
2
3
23
odology. (S)-(-)-1-Phenyl-1-propanol (3): purified by
distillation at 130 °C, 0.5 mmHg (lit. 150 °C, 0.3 mmHg),
R R
(standard conditions) t [(R)-alcohol] 63 min, t
4
64 min.
to give a colourless oil, the alcohol 3 (typically 1.36 g, 90%);
(S)-(-)-1-(2′-Methoxyphenyl)-1-propanol (8): purified by
2
1
25
25
33
[
R] -24.7 (neat) [lit. [R]D -22.2 (neat)]; R
f
0.40 (50%
, 200 MHz) 7.39-7.18
5H, m, Ph), 4.59 (1H, t, J 6.6, CHOH), 1.90-1.66 (3H, m,
distillation at 150 °C, 0.2 mmHg (lit. 78-80 °C, 0.1
D
21
diethyl ether in pentane); δ
(
H
(CDCl
3
mmHg), to give a colourless oil, the alcohol 8; [R] -20.8
D
27
2
6
(c 3.4, toluene) [lit. [R]D -50.63 (c 3, toluene)]; R
(50% diethyl ether in pentane); δ (CDCl , 200 MHz) 7.34-
7.21 (2H, m, 2 × aryl H), 7.01-6.87 (2H, m, 2 × aryl H),
4.81 (1H, t, J 6.6, CHOH), 3.85 (3H, s, OCH ), 1.90-1.75
(2H, app pentet, J 7.0, CH ), and 0.97 (3H, t, J 7.5, CH );
[(R)-alcohol] 72 min, t [(S)-
f
0.42
CH
conditions) t
2
+ OH) and 0.91 (3H, t, J 7.5, CH
[(R)-alcohol] 45 min, t [(S)-alcohol] 46 min.
S)-(+)-3-Undecanol (4): purified by distillation at 100-
3
); CGC (standard
H
3
R
R
26
(
3
27
120 °C, 0.2 mmHg (lit. 134-137 °C, 37 mmHg), to give
2
3
21
a colourless oil, the alcohol 4; [R] +5.2 (c 8.96, EtOH)
CGC (standard conditions) t
R
R
D
2
8
26
[
lit. [R]D +7.79 (c 8.63, EtOH)]; R
ether in pentane); δ (CDCl , 200 MHz) 3.56-3.44 (1H,
m, CHOH), 1.61-1.25 (16H, m, 8 × CH ), 0.92 (3H, t, J
.5, CH ), and 0.86 (3H, t, J 6.6, CH ); CGC (standard
conditions) t
[(R+S)-alcohol] 63 min; 19F NMR analysis
of R and S Mosher esters, δ (CDCl , 282 MHz) -71.8 and
71.9 (CF ).
S)-(+)-1-Phenyl-3-pentanol (5): purified by distillation
f
0.47 (50% diethyl
alcohol] 68 min.
(-)-1-Phenyl-4-penten-1-ol (9): purified by flash column
H
3
chromatography (25% diethyl ether in pentane) to give a
2
2
1
7
3
3
colourless oil, the alcohol 9 (1.49 g, 83%); [R] -18.1 (c
D
23
3.27, CHCl
3
) [lit. [R]
D
-31.9 (c 3.2, CHCl
3 f
)]; R 0.60 (50%
R
diethyl ether in pentane); δ
H
(CDCl , 200 MHz) 7.38-7.27
3
F
3
-
3
(5H, m, Ph), 5.96-5.76 (1H, m, alkene CH), 5.10-4.98 (2H,
29
(
m, 2 × alkene CH), 4.72 (1H, t, J 6.5, CHOH), 2.22-2.05
30
at 135 °C, 0.5 mmHg (lit. 98-100 °C, 0.03 mmHg), to
(2H, m, CH
2
), and 2.01-1.76 (3H, m, CH + OH); CGC
2
2
give a colourless oil, which solidified on standing, the alcohol
(TFA ester, conditions: 80 °C isotherm, 1.0 kg/cm of H
2
2
D
1
26
27
pressure) t
R
[(R)-alcohol] 125 min, t
R
2
[(S)-alcohol] 121 min.
5
; [R] +20.3 (c 5.07, EtOH) [lit. [R]D +26.8 (c 5,
3
(S)-(-)-1-Phenyl-1-ethanol (10): purified by flash col-
EtOH)]; R
00 MHz) 7.32-7.14 (5H, m, Ph), 3.61-3.46 (1H, m,
CHOH), 2.87-2.58 (2H, m, CH ), 1.89-1.72 (2H, m, CH ),
.58-1.38 (3H, m, CH + OH), and 0.94 (3H, t, J 7.5, CH );
CGC (standard conditions) t
NMR analysis of R and S Mosher esters δ
MHz) 0.94 and 0.84 (CH ).
f
H 3
0.41 (50% diethyl ether in pentane); δ (CDCl ,
umn chromatography (25% diethyl ether in pentane) to give
2
21
a colourless oil, the alcohol 10 (0.79 g, 58%); [R] -24.3
D
25
2
2
3
4
1
2
3
1
(c 1.9, CHCl
(50% diethyl ether in pentane); δ
7.25 (5H, m, Ph), 4.89 (1H, q, J 6.5, CHOH), 2.44 (1H, s,
OH), and 1.50 (3H, d, J 6.3, CH ); CGC (standard conditions)
[(R)-alcohol] 36 min, t
isolated was PhCHO (0.47 g).
3
) [lit. [R]D -58 (c 1.7, CHCl
3 f
)]; R 0.41
[(R+S)-alcohol] 45 min; H
(CDCl , 300
H
(CDCl , 200 MHz) 7.42-
3
R
H
3
3
3
3
1
(
+)-4-Octen-3-ol (6): purified by distillation at 100 °C,
t
R
R
[(S)-alcohol] 37 min. Also
3
2
5
mmHg (lit. 87 °C, 16 mmHg), to give a colourless oil,
the alcohol 6; [R]D +10.2 (c 5.15, EtOH); R
21
23
0.42 (50%
(S)-(-)-1,3-Diphenyl-1-propanol (11): purified by flash
f
diethyl ether in pentane); δ (CDCl , 200 MHz) 5.63 (1H,
H
3
column chromatography (25% diethyl ether in pentane) to
2
D
1
give a colourless oil, the alcohol 11 (1.41 g, 60%); [R]
3
5
(
(
(
(
25) Beilsteins Handbuch der Organischen Chemie, 6 EIII, 1793.
-6.16 (c 5.7, EtOH) [lit. [R]
D
-15.6 (c 5, EtOH)]; R
50% diethyl ether in pentane); δ (CDCl
.16 (10H, m, 2 × Ph), 4.75-4.67 (1H, m, CHOH), 2.86-
.61 (2H, m, CH ), 2.25-2.02 (2H, m, CH ), and 1.86 (1H,
f
0.56
26) Kaufmann, T.; Neiteler, C.; Neiteler, G. Chem. Ber. 1994, 127, 659.
27) Rickborn, B.; Wood, S. E. J. Am. Chem. Soc. 1971, 93, 3940.
28) Soai, K.; Yokoyama, S.; Ebihara, K.; Hayasaka, T. J. Chem. Soc., Chem.
Commun. 1987, 1690.
(
7
2
H
3
, 200 MHz) 7.39-
2
2
(29) Ishizaki, M.; Fujita, K.-I.; Shimamoto, M.; Hoshino, O. Tetrahedron:
Asymmetry 1994, 5, 411.
(
(
30) Beilsteins Handbuch der Organischen Chemie, 6 EII, 504; EIII, 1953.
31) Teo, K.-E.; Barnett, G. H.; Anderson, H. J.; Loader, C. E. Can. J. Chem.
(33) Bromley, L. A.; Davies, S. G.; Goodfellow, C. L. Tetrahedron: Asymmetry
1991, 2, 139.
1
978, 56, 221.
(34) Garcia, C.; Collet, A. Tetrahedron: Asymmetry 1992, 3, 361.
(35) Beilsteins Handbuch der Organischen Chemie, 6 EII, 643.
(
32) Schnurpfeil, D. J. Prakt. Chem. 1988, 330, 487.
Vol. 2, No. 1, 1998 / Organic Process Research & Development
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