Chemistry Reference
In-Depth Information
C
8
H
17
C
8
H
17
CDI
O
HN
THF, 20 °C
OH
H
2
N
O
678
679
Typical procedure. (4S,5R)-5-[(E)-Dec-1-en-1-yl]-4-methyl-2-oxazolidinone [451]:
In a
flame-dried reaction flask were placed the amino alcohol (119 mg, 0.56 mmol),
CDI (118 mg, 0.73 mmol), and freshly distilled THF (2 mL). The resulting solution
was stirred for 2 h at room temperature. The THF was then evaporated, the residue
was redissolved in Et
2
O, and this solution was washed with 1 n HCl (3
) and with
saturated NaHCO
3
(1
), and dried (K
2
CO
3
). Removal of the solvent under reduced
pressure provided the crude material. Chromatography (EtOAc/hexane, 1:1) fur-
nished 93 mg (70%) of pure product.
The stereochemistry of the amino alcohol anti-680 was unequivocally assigned
through its oxazolidone derivatives 681 and 682 prepared with CDI [452].
O
Bn
Bn
OBn
OBn
O
O
(i),(ii)
NHBoc
C
13
H
27
HN
O
+
3'
95 %
BnO
BnO
4'
H
H
OBn
OBn
OH
C
13
H
27
anti (syn/anti 5:95)
J
3',4'
= 6.0 Hz
680
681
(i) HCl/dioxane (4.8 M);
(ii)
CDI
, THF
O
Bn
OBn
O
HN
O
3'
BnO
4'
H
H
OBn
C
13
H
27
J
3',4'
= 8.0 Hz
682
Typical procedure. Oxazolidinones 681 and 682 [452]:
A mixture of epimers 680
(0.13 g, 0.14 mmol) was dissolved in a solution of HCl in dioxane (4.8 m, 3.0 mL)
containing water (0.50 mL). The solution was stirred at room temperature for 14 h
and then concentrated. The residue was redissolved in anhydrous THF (2.0 mL),
treated with CDI (0.03 g, 0.21 mmol) at 0
C, and the resulting mixture was stirred
for 45 min at room temperature and then concentrated. The
1
H NMR spectrum of
the crude residue showed it to be a mixture of 681 and 682 in a ratio of ca. 70:30.
Chromatography of this mixture on silica gel eluting with cyclohexane/AcOEt (2:1)
