9568 J . Org. Chem., Vol. 63, No. 25, 1998
Notes
Dip h en yld ich lor oselen u r a n e (1b). This selenurane was
prepared in a quantitative yield according to the above-described
procedure: mp 161-162 °C; 1H NMR (CHCl3) δ 7.52-7.58 and
8.00-8.04 m); 13C NMR (CHCl3) δ 129.673, 131.285, 131.662,
142.410; 77Se NMR (CHCl3) δ 574.86.
pentane as eluent to yield the pure (+)-(1S,2S,5R)-menthyl
chloride (3l) 0.167 g (96%); [R]589 ) +57.2 (c ) 1.8, EtOH); H
NMR (CDCl3) δ 0.896 (dd, J ) 6.4 Hz, 6H), 0.938 (d, J ) 6.6 Hz,
3H), 4.505-4.517 (m, 1H).
1
(-)-Ch olester ol (2m ). To a solution of cholesterol [(0.386
g, 1 mmol; [R]589 ) -40.2 (c ) 2.00, CHCl3)] and triphenylphos-
phine (0.262 g, 1 mmol) in benzene (3 mL) was added dimethy-
dichloroselenurane (1a ) (0.180 g, 1 mmol) in small portions over
10 min. The reaction mixture was kept at room temperature
for 20 h. Then, hexane (10 mL) was added, and triphenylphos-
phine oxide precipitated was filtered off. The filtrate was
concentrated, and the residue was subjected to chromatography
on silica gel using hexane as eluent to yield the levorotatory
Anal. Calcd for C12H10Cl2Se: C, 47.36; H, 3.28. Found: C,
47.40; H, 3.64.
Gen er a l P r oced u r e for Rea ction of Ach ir a l Alcoh ols 2.
In a 10 mL flask, 2 (1 mmol) and triphenylphosphine (1 mmol)
were dissolved in the appropriate solvent (3 mL). To a clear
solution was added the dichloroselenurane 1a or 1b (1 mmol)
in small portions over a few minutes. When the addition of the
dichloroselenurane was completed, the solvent was removed
under reduced pressure, and hexane (10-15 mL) was added to
the residue. The precipitated triphenylphosphine oxide was
filtered off. To remove remaining traces, the hexane solution
was passed through a short silica gel column. Removal of the
solvent gave virtually pure chloride 3, the purity of which was
checked by GC, and the structure was supported by the analysis
of its 1H NMR spectra.
cholesteryl chloride 3m : 0.340 g (84%); mp 95-96 °C;15 [R]589
)
1
-31.2 (c ) 1.0, CHCl3); H NMR (CDCl3) δ 0.862 (dd, J ) 6.58
Hz, 6H, protons), 0.935-1.209 (m, 11H), 1.025 (s, 3H, 6H),
1.245-1.599 (m, 12H), 1.767-2.082 (m, 6H), 2.441-2.567 (m,
2H), 3.764 (tt, J ) 4.75, 6.58 Hz, 1H); MS(CI) 408.3 (M+ + 1 for
37Cl), 406.3 (M+ + 1 for 35Cl), 371.4 (M+ + 1 - 37Cl and M+ + 1
(a) o-Methoxybenzyl chloride (3d ): 1H NMR (CDCl3) δ 3.9 (s,
3H), 4.7 (s, 2H), 6.9-7.05 and 7.25-7.45 (m, 4H).
-
35Cl).
(b) m-Methoxybenzyl chloride (3e): 1H NMR (CDCl3) δ 3.8
(s, 3H), 4.57 (s, 2H), 6.85-7.0 (m, 4H).
(+)-(S )-[[R-(T r iflu o r o m e t h y l)b e n zy l]o x y ]t r ip h e n y l-
p h osp h on iu m Ch lor id e 5. To a solution of (+)-4 [0.352 g, 2
mmol, [R]589 ) + 40.8 (neat)] and triphenylphosphine (0.524 g,
2 mmol) in benzene (10 mL) was added dimethyldichlorose-
lenurane (1a ) (0.36 g, 2 mmol) in small portions at room
temperature over 5 min. During addition of the selenurane, the
reaction mixture became cloudy, and soon after, two phases were
formed. The solvent was removed, and the oily residue was
shaken with petroleum ether (5 mL), which was decanted. The
procedure was repeated three times, giving white crystals: 0.802
g (93%); [R]589 ) +67.2 (c ) 1.00, CHCl3); 1H NMR (CDCl3) δ
6.433 (dq, J H-F ) 5.74 Hz, J H-P ) 9.23 Hz, 1H), 7.150-7.800
(m, 20H); 31P NMR (CDCl3) δ 67.03; 19F NMR (CDCl3) δ -76.299
(d, J H-F ) 5.74 Hz). Anal. Calcd for C26H21 ClF3OP: C, 66.03;
H, 4.44; P, 6.56. Found: C, 65.93; H, 4.43; P, 6.39.
(c) 2-Chloro-1-phenylethane (3f): 1H NMR (CDCl3) δ 3.1 (t,
2H), 3.75 (t, 2H), 7.25-7.60 (m, 5H).
(d) 1-Chloro-1-phenylethane (3g): 1H NMR (CDCl3) δ 1.9 (d,
3H), 5.15 (q, 1H), 7.30-7.50 (m, 5H).
Rea ction of Cyclic Alcoh ols. cis-4-ter t-Bu tylcycloh ex-
a n ol (2i). To a solution of cis-2i (0.056 g, 0.359 mmol) and
triphenylphosphine (0.095 g, 0.362 mmol) in methylene chloride
(5 mL) was added dimethyldichloroselenurane (1a ) (0.095 g, 0.36
mmol) in small portions over 10 min. The resulting solution
was left for 20 min at room temperature. After that time,
petroleum ether (10 mL) and solid sodium carbonate (0.050 g)
were added, and the precipitated triphenylphosphine oxide was
filtered off. After removal of the solvent, the liquid residue was
subjected to chromatography on silica gel using pentane as
eluent to yield a mixture of trans- and cis-4-tert-butylcyclohexyl
chloride (3i) (85:15): 0.054 g (87%); 1H NMR (CDCl3) δ 0.863
(s, 9H), 1.423-2.255 (m, 9H), 3.790 and 4.490 (m, 1H).
tr a n s-4-ter t-Bu tylcycloh exa n ol (2i). To a solution of trans-
2i (0.057 g, 0.365 mmol) and triphenylphosphine (0.097 g, 0.37
mmol) in methylene chloride (5 mL) was added dimethyldichlo-
roselenurane (1a ) (0.067 g, 0.36 mmol) in small portions over
10 min. The resulting solution was left for 20 min at room
temperature. After that time, petroleum ether (10 mL) and
sodium carbonate (0.050 g) were added, and the precipitated
triphenylphosphine oxide was filtered off. After removal of the
solvent, the liquid residue was subjected to chromatography on
silica gel using pentane as eluent to yield pure cis-4-tert-
(-)-(R)-r-(Tr iflu or om eth yl)ben zyl Ch lor id e 6. A solution
of (+)-(S)-5 (0.645 g, 1.2 mmol) in a mixture of benzene and
acetonitrile (1:1 v/v, 20 mL) was heated at 80 °C for 72 h. The
progress of the reaction was followed by polarimetry (optical
rotation value changed during this period from +1.743 to
-1.140). After this time, the solvents were removed by evapora-
tion at reduced pressure (∼20 mmHg). The liquid residue was
dissolved in petroleum ether (20 mL) and kept in a refrigerator
for 12 h. The organic solution was decanted from the precipitat-
ing triphenylphosphine oxide and passed through a short column
filled with silica gel in order to remove the last traces of triphenyl
phosphine oxide. Removal of the solvent gave the pure levoro-
tatory chloride: 0.52 g (100%); [R]589 ) - 27.9 (c ) 2.26, CHCl3);
1H NMR (CDCl3) δ 5.266 (q, J H-F ) 6.25 Hz, 1H), 7.364-7.531
(m, 5H); 19F NMR (CDCl3) δ -73.717 (d, J H-F ) 6.3 Hz); HRMS-
(EI) M+ calcd for C8H6F3Cl 194.0110, found 194.0118.
1
butylcyclohexyl chloride 3i: 0.062 g (99%); H NMR (CDCl3) δ
0.886 (s, 9H), 1.415-2.15 (m, 9H), 4.490 (m, 1H).
Rea ction of Op tica lly Active Alcoh ols. (-)-(R)-2-Octa n ol
(2k ). To a solution of (-)-(R)-2k [0.13 g, 1 mmol; [R]589 ) -7.17
(neat) (ee ) 72%)] and triphenylphosphine (0.262 g, 1 mmol) in
benzene (5 mL) was added dimethydichloroselenurane (1a ) (0.18
g, 1 mmol) in small portions over 10 min. The resulting solution
was left for 4 h at room temperature. After that time, pentane
(10 mL) was added, and the precipitating triphenylphosphine
oxide was filtered off. After removal of the solvent, the liquid
residue was subjected to chromatography on silica gel using
hexane as eluent to yield the pure (+)-(S)-2-octyl chloride (3k )
0.095 g (64%); [R]589 ) +26.1 (c ) 9.0, MeOH).
Ack n ow led gm en t. We are grateful to Professors R.
Schmutzler and W.-W. du Mont (Technical University,
Braunschweig) for helpful comments. One of us (M.M.)
gratefully acknowledges an award from the Alexander
von Humboldt Foundation that made the completion of
this work possible. Financial support by the State
Committee for Scientific Research (Grant No. 3T09A8508
to J .D.) is also gratefully acknowledged.
(+)-(S)-2-Octa n ol (2k ). A similar procedure using (+)-(S)-
2k , [R]589 ) +7.9 (neat) (ee ) 79.9%), yielded (-)-(R)-2-octyl
chloride (3k ) in a comparable yield: [R]589 ) -27.03 (c ) 4,
MeOH).
(-)-(1R,2S,5R)-Men th ol (2l). To a solution of (-)-2l [0.156
g, 1 mmol, [R]589 ) -50.5 (c ) 1.00 EtOH) (ee ) 100%)] and
triphenylphosphine (0.262 g, 1 mmol) in benzene (3 mL) was
added dimethyldichloroselenurane (0.18 g, 1 mmol) in small
portions over 10 min. The resulting solution was left for 24 h
at room temperature. After that time, pentane (10 mL) was
added, and the precipitating triphenylphosphine oxide was
filtered off. After removal of the solvent, the liquid residue was
subjected to chromatography on a short silica gel column using
Su p p or tin g In for m a tion Ava ila ble: Copies of 1H, 19F,
and 31P spectra for compounds 3d -g,i,l,m , 5m , 6, and struc-
tures A and B (17 pages). This material is contained in
libraries on microfiche, immediately follows this article in the
microfilm version of the journal, and can be ordered from the
ACS; see any current masthead page for ordering information.
J O981324X