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1579
s), 3.8 (3H, s), 4.0 (2H, t, J=6.54), 5.7 (1H, dd,
J=6.57, 7.38), 6.8 (2H, d, J=8.72), 7.2 (2H, d, J=
8.72); EIMS (m/z): 280 (M+−36), 237 (M+−43); anal.
calcd for C15H20O5: C, 64.27; H, 7.19. Found: C, 64.12;
H, 7.02%.
Hz), 7.2 (2H, d, J=8.90 Hz); EIMS (m/z): 196 (M+),
137 (M+−59); anal. calcd for C11H16O3: C, 67.32; H,
8.22, Found: C, 67.28; H, 8.10%.
4.4.3. 1-(4-Chlorophenyl)-(1S)-butane-1,4 diol 2c. Yield:
96%; mp 83–84°C; [h]2D5 −42.4 (c 0.82, CHCl3); IR
(neat): 3380 cm−1 (broad); 1H NMR (200 MHz,
CDCl3): l 1.6–1.9 (4H, m), 3.7 (2H, m), 4.8 (1H, t,
J=6.20 Hz), 7.3 (4H, m); EIMS (m/z): 166 (M+), 107
(M+−59); anal. calcd for C10H13ClO2: C, 59.86; H, 6.53;
Cl, 17.67. Found: C, 59.64; H, 6.48; Cl, 17.50%.
4.3.5. (S)-4-(4-Chlorophenyl)-4-hydroxybutyl acetate 5c.
Yield: 36%; 92% ee;22a tR 18.86 min; [h]2D5 −17.0 (c 0.47,
1
benzene); IR (KBr): 3454, 1735 cm−1; H NMR (400
MHz, CDCl3): l 1.5–1.8 (4H, m), 2.0 (3H, s), 4.0 (2H,
t, J=5.94), 4.6 (1H, dd, J=7.06, 4.83), 7.3 (4H, m);
EIMS (m/z): 242 (M+), 141 (M+−101); anal. calcd for
C12H15ClO3: C, 59.39; H, 6.23; Cl, 14.61. Found: C,
59.35; H, 6.20; Cl, 14.53%.
4.4.4. 1-Phenyl-(1S)-pentane-1,5 diol 2d. Yield: 99%;
65% ee;22a [h]D251 −25.4 (c 1.28, benzene); IR (neat): 3353
cm−1 (broad); H NMR (200 MHz, CDCl3): l 1.2–1.8
(6H, m), 3.5 (2H, t, J=5.73 Hz), 4.5 (1H, t, J=6.24
Hz), 7.2–7.4 (5H, m); EIMS (m/z): 180 (M+); anal.
calcd for C11H16O2: C, 73.30; H, 8.95. Found: C, 73.18;
H, 8.82%.
4.3.6.
1-(4-Chlorophenyl)-4-methylcarbonyloxy-(1R)-
butyl acetate 6c. Yield: 41%; 77% ee22c tR 15.93 min;
[h]2D5 +60.4 (c 0.48, benzene); IR (KBr): 1730 cm−1; H
1
NMR (200 MHz, CDCl3): l 1.5–1.8 (4H, m), 2.02 (3H,
s), 2.05 (3H, s), 4.0 (2H, t, J=6.32), 5.6 (1H, dd,
J=5.94, 7.43), 7.3 (4H, m); EIMS (m/z): 183 (M+−103);
anal. calcd for C14H17ClO4: C, 59.06; H, 6.02; Cl, 12.45.
Found: C, 59.94; H, 6.00; Cl, 12.33%.
4.5. Oxidation of diol 2 to (S) and (R) lactone 115
A solution of diol 2 (1 mmol), TEMPO (0.1 mmol, 15.6
mg), TBAI (0.1 mmol, 37.0 mg), in 10 mL of
dichloromethane and 10 mL of an aqueous solution of
NaHCO3 (0.5 M) and K2CO3 (0.05 M) were vigorously
stirred at room temperature. N-Chlorosuccinamide (3
mmol, 400 mg) was then added and the reaction was
monitored for the completion. The organic layer was
separated, and the aqueous phase was extracted with
CH2Cl2 (10 mL). The dichloromethane extract were
washed with brine, dried, and evaporated. The residue
was purified by silica gel column chromatography.
4.3.7. (S)-5-Hydroxy-5-phenylpentyl acetate 5d. Yield:
46%; 67% ee (from the chiral HPLC of 2d)22a tR 21.51
min; [h]2D5 −28.8 (c 0.97, benzene); IR (KBr): 3450, 1735
1
cm−1; H NMR (200 MHz, CDCl3): l 1.3–1.9 (6H, m),
2.0 (3H, s), 4.0 (2H, t, J=6.69 Hz), 4.6 (1H, t, J=6.69
Hz), 7.2–7.4 (5H, m); EIMS (m/z): 222 (M+); anal.
calcd for C13H18O3: C, 70.25; H, 8.16. Found: C, 70.05;
H, 8.0%.
4.3.8. 5-Methylcarbonyloxy-1-phenyl-(1R)-pentyl acetate
6d. Yield: 39%; 94% ee;22a tR 11.76 min; [h]D25 +43.2 (c
4.5.1. 5-Phenyl-5(R)-tetrahydro-2-furanone 1a10b. Yield:
78%; 70% ee (from the chiral HPLC of 2a);22a [h]D25
+10.5 (c 0.91, CH2Cl2); lit.10b [h]D25 +31.0 (c 0.67,
1
0.98, benzene); IR (KBr): 1730 cm−1; H NMR (200
MHz, CDCl3): l 1.3–1.9 (6H, m), 2.0 (3H, s), 2.1 (3H,
s), 4.0 (2H, t, J=6.68 Hz), 5.7 (1H, dd, J=7.42, 5.94
Hz), 7.2–7.4 (5H, m); EIMS (m/z): 264 (M+); anal.
calcd for C15H20O4: C, 68.16; H, 7.63. Found: C, 67.98;
H, 7.35%.
1
CH2Cl2); IR (KBr): 1769 cm−1; H NMR (200 MHz,
CDCl3): l 2.2 (1H, m), 2.5–2.7 (3H, m), 5.5 (1H, t,
J=7.2 Hz), 7.3 (5H, m); EIMS (m/z): 162 (M+), 107
(M+−55); anal. calcd for C10H10O2: C, 74.60; H, 6.21.
Found: C, 74.0; H, 6.30%.
4.4. General procedure for ester hydrolysis reaction
4.5.2. 5-(4-Methoxyphenyl)-(5R)-tetrahydro-2-furanone
1b10b. Yield: 83%; >99% ee;21 [h]2D5 +5.5 (c 1.06,
CH2Cl2); lit.10b [h]D25 +4.9 (c 1.30, CH2Cl2); IR (KBr):
1770 cm−1; 1H NMR (200 MHz, CDCl3): l 2.1–2.3 (2H,
m), 2.4–2.7 (2H, m), 3.8 (3H, s), 5.4 (1H, t, J=6.0 Hz),
6.9 (2H, d, J=8.54 Hz), 7.2 (2H, d, J=8.54 Hz); EIMS
(m/z): 192 (M+); anal. calcd for C11H12O3: C, 68.74; H,
6.29. Found: C, 78.67; H, 6.24%.
To the solution of ester 5 and 6 (1 mmol) in 10 mL
methanol was added K2CO3 (1.5 mmol) and (2.5
mmol), respectively. The mixture was stirred for 4 h,
acidified with 1N HCl and extracted with ether, after
evaporation of the methanol.
4.4.1. 1-Phenyl-(1S)-butane-1,4 diol 2a. Yield: 98%; mp
82–83°C; >97% ee;22a [h]2D5 −28.0 (c 1.27, methanol); IR
(KBr): 3350 cm−1 (broad); 1H NMR (200 MHz,
CDCl3): l 1.6 (2H, m), 1.8 (2H, m), 3.7 (2H, t, J=5.73
Hz), 4.7 (1H, t, J=6.24 Hz), 7.4 (5H, m); EIMS (m/z):
166 (M+), 107 (M+−59); anal. calcd for C10H14O2: C,
72.26; H, 8.49. Found: C, 72.15; H, 8.30%.
4.5.3. 5-(4-Chlorophenyl)-(5R)-tetrahydro-2-furanone 1c.
Yield: 68%; 76% ee; [h]2D5 +14.8 (c 0.46, CH2Cl2); IR
(neat): 1770 cm−1; 1H NMR (200 MHz, CDCl3): l
2.0–2.2 (2H, m), 2.6 (2H, m), 5.4 (1H, t, J=6.69 Hz),
7.3 (4H, m); EIMS (m/z): 198 (M++2), 196 (M+); anal.
calcd for C10H9ClO2: C, 61.08; H, 4.61; Cl, 18.03.
Found: C, 61.00; H, 4.56; Cl, 17.93%.
4.4.2. 1-(4-Methoxyphenyl)-(1S)-butane-1,4 diol 2b.
Yield: 97%; mp 60°C; >99% ee;22a [h]D25 −25.9 (c 1.20,
1
benzene); IR (neat): 3354 cm−1 (broad); H NMR (200
4.5.4. 6-Phenyl-(6R)-tetrahydro-2H-2-pyranone 1d7a.
Yield: 72%; 90% ee;22b [h]D25 +41.4 (c 1.01, CHCl3); lit.7a
MHz, CDCl3): l 1.5 (2H, m), 1.8 (2H, m), 3.6 (2H, m),
3.8 (3H, s), 4.6 (1H, t, J=6.74 Hz), 6.8 (2H, d, J=8.90
1
[h]D25 +38.5 (c 1.0, CHCl3); IR (KBr): 1740 cm−1; H