8896 J . Org. Chem., Vol. 63, No. 24, 1998
Mikołajczyk and Z˙ urawin´ski
extracted with CHCl3 (3 × 50 mL). The combined organic
extracts were dried over anhydrous MgSO4 and concentrated
under vacuum. An excess of dimethyl methanephosphonate
2 was removed under vacuum using a Kugelrohr apparatus
(75 °C/0.01 mmHg). The remaining crude dimethyl 2-oxoun-
decanephosphonate 3 (44.8 g, 100%, calculated with respect
to carboxylic ester) was used without purification for the next
reaction. An analytically pure sample was obtained by distil-
lation under reduced pressure: bp 140-2 °C/0.01 mmHg; Rf
benzene (70 mL) at room temperature was added Al2O3-KOH
[obtained by evaporation under reduced pressure of a mixture
of Al2O3 (1.5 g) and saturated aqueous solution of KOH (0.5 g,
9.0 mmol)]. After stirring for 3 h, the mixture was filtered on
a Celite pad, concentrated in vacuo, and chromatographed on
silica gel using hexane/ethyl acetate (4:1) as eluent affording
7 (2.12 g, 76%) as a mixture of isomers (E/ Z ) 1.3:1). Pure
isomers were separated and characterized.
Z-7: n22 ) 1.4770; Rf ) 0.44 (hexane/AcOEt 4:1); 1H NMR
D
) 0.17 (hexane/AcOEt 1:1); n20 ) 1.4481; 31P NMR δ 23.10;
(C6D6, 300 MHz) δ 5.64 (dt, J ) 7.6, J ) 2.3, 1H), 3.34 (s, 3H),
2.90-2.78 (m, 2H), 2.35-2.23 (m, 1H), 2.08 (t, J ) 7.4, 2H),
2.18-1.87 (m, 2H), 1.72-1.02 (m, 18H), 0.93 (t, J ) 6.9, 3H);
13C NMR δ 207.7, 173.9, 140.8, 139.8, 51.6, 43.0, 39.2, 35.5,
34.7, 32.9, 30.5, 30.2, 29.8, 28.4, 27.8, 27.3, 25.8, 23.8, 15.0;
MS (15 eV) m/e (%) 309 (M+ + 1, 4), 308(M+, 19), 191 (100);
HRMS (CI) (M + H)+ calcd for C19H33O3 309.2430, odsd
309.2435.
D
1H NMR δ 3.37 (d, J ) 11.1, 6H), 2.71 (d, J ) 22.6, 2H), 2.36
(t, J ) 7.2, 2H), 1.64-1.45 (m, 2H), 1.38-1.10 (m, 12H), 0.91
(t, J ) 6.5, 3H); 13C NMR δ 202.12, 53.14 (d, J ) 5.6), 44.55,
42.03 (d, J ) 126.3), 32.88, 30.49, 30.46, 30.32, 29.97, 24.32,
23.65, 14.90; MS (15 eV) m/e (%) 278 (M+, 3), 166 (100); HRMS
(CI) (M + H)+ calcd for C13H28O4P 279.1725, obsd 279.1720.
Dim eth yl 1-Dia zo-2-oxou n d eca n ep h osp h on a te (4). To
a magnetically stirred suspension of NaH (3.9 g; 0.162 mol)
in THF (100 mL) and benzene (500 mL) under nitrogen at 0
°C was added dropwise dimethyl 2-oxoundecanephosphonate
3 (41.0 g, 0.147 mol) in benzene (150 mL). After 1.5 h of
stirring, tosyl azide (32.0 g, 0.162 mol) in benzene (80 mL) was
added and the reaction mixture was allowed to warm to room
temperature. After 4 h, the mixture was filtered on a Celite
pad, concentrated in vacuo, and chromatographed on silica gel
(ethyl acetate-hexane gradient as an eluent) affording dim-
ethyl 1-diazo-2-oxoundecanephosphonate 4 (38.2 g, 85%) as a
E-7: n25D ) 1.4715; Rf ) 0.34 (hexane/AcOEt 4:1); 1H NMR
(C6D6, 300 MHz) δ 6.66 (dt, J ) 7.6, J ) 1.9, 1H), 3.35 (s, 3H),
2.72-2.57 (m, 1H), 1.60-1.00 (m, 24H), 0.91 (t, J ) 6.9, 3H);
13C NMR δ 205.79, 173.83, 142.95, 135.90, 51.60, 39.34, 36.66,
35.66, 34.55, 32.88, 30.43, 29.98, 29.73, 29.36, 28.53, 25.81,
25.64, 23.73, 15.00; MS (15 eV) m/e (%) 309 (M+ + 1, 5), 308
(M+, 29), 191 (100); HRMS (CI) (M + H)+ calcd for C19H33O3
309.2430, obsd 309.2430.
Meth yl 2-Hexyl-5-oxocyclop en ta n eh ep ta n oa te (8). To
a magnetically stirred tellurium powder (0.319 g, 2.5 mmol)
in ethanol (10 mL) under a possitive pressure of an inert gas
was added sodium borohydride (0.123 g, 3.3 mmol) in one
portion. The reaction mixture was warmed to 40 °C, and when
a clear, almost colorless solution was formed, the temperature
was lowered to 0 °C and acetic acid (0.1 mL) was added. The
solution of 7 (0.308 g, 1 mmol) in ethanol (1 mL) was added,
and the reaction mixture was stirred for 5 h at room temper-
ature and then filtered through Celite and concentrated. The
residual liquid was purified by column chromatography (hex-
ane/ethyl acetate 4:1) affording 8 (0.295 g, 95%) as a colorless
light yellow liquid: n22 ) 1.4683; Rf ) 0.35 (hexane/AcOEt
D
1:1); 31P NMR (CDCl3) δ 15.13; H NMR (CDCl3) δ 3.79 (d, J
1
) 11.9, 6H), 2.48 (t, J ) 7.4, 2H), 1.65-1.47 (m, 2H), 1.32-
1.15 (m, 12H), 0.83 (t, J ) 6.5, 3H); 13C NMR (CDCl3) δ 191.97
(d, J ) 13.5), 62.23 (d, J ) 220.5), 53.06 (d, J ) 4.6), 38.92,
31.40, 28.95, 28.92, 28.80, 28.68, 23.82, 22.19, 13.59; MS (15
eV) m/e (%) 305 (M+ + 1, 6), 151 (100); HRMS (CI) (M + H)+
calcd for C13H26N2O4P 305.1630, obsd 305.1624.
2-Dim eth oxyp h osp h or yl-3-h exylcyclop en ta n -1-on e (5).
To a refluxing solution of the dirhodium (II) tetraacetate (0.19
g, 0.43 mmol) in 400 mL of CH2Cl2 was added slowly dimethyl
1-diazo-2-oxoundecanephosphonate 4 (12.5 g, 41 mmol) in 50
mL of CH2Cl2. Reflux was continued until disappearance of
the substrate (about 2 h, monitored by TLC). After cooling,
the resulted solution was washed with water (2 × 30 mL) and
dried over anhydrous Na2SO4. The solvent was removed under
reduced pressure, and the residue was purified by column
chromatography (ethyl acetate/hexane gradient as an eluent)
liquid: n21 ) 1.4605; Rf ) 0.40 (hexane/AcOEt 4:1); 1H NMR
D
δ 3.35 (s, 3H), 2.16-1.96 (m, 2H), 2.10 (t, J ) 7.4, 2H), 1.82-
0.85 (m, 24H), 0.93 (t, J ) 6.9, 3H); 13C NMR δ 218.97, 173.97,
55.50, 51.61, 42.43, 38.35, 35.73, 34.75, 32.92, 30.65, 30.61,
29.97, 29.09, 28.07, 27.84, 27.80, 25.92, 23.75, 15.03; MS (15
eV) m/e (%) 310 (M+, 4), 83 (100); HRMS (CI) (M + H)+ calcd
for C19H35O3 311.2586, obsd 311.2595.
2-Hexyl-5-oxocyclop en ta n eh ep ta n oic Acid (9). A solu-
tion of methyl 2-hexyl-5-oxocyclopentaneheptanoate 8 (0.155
g, 0.5 mmol) in 95% ethanol (6 mL) was heated at 45 °C with
3 mL of aqueous 1 N NaOH. After 3 h the reaction mixture
was concentrated under reduced pressure, acidified by addition
of 5% aqueous HCl, and extracted with chloroform. The
organic extracts were dried over Na2SO4 and concentrated, and
the residue was purified by column chromatography (hexane/
affording 5 (9.4 g, 83%) as a colorless liquid: n21 ) 1.4619;
D
1
Rf ) 0.20 (hexane/AcOEt 1:1); 31P NMR δ 26.01; H NMR δ
3.59 (d, J ) 10.8, 3H), 3.40 (d, J ) 11.0, 3H), 2.65-2.38 (m,
1H), 2.24 (dd, J ) 25.8, J ) 8.4, 1H), 2.15-1.75 (m, 3H), 1.70-
1.50 (m, 1H), 1.38-0.85 (m, 10H), 0.90 (t, J ) 6.6, 3H); 13C
NMR δ 211.37 (d, J ) 3.4), 53.91 (d, J ) 6.6), 53.72 (d, J )
134.8), 52.60 (d, J ) 6.8), 39.49, 39.35 (d, J ) 4.6), 36.19 (d, J
) 5.3), 32.74, 30.21, 28.54 (d, J ) 10.6), 27.75, 23.63, 14.93;
MS (15 eV) m/e (%) 276 (M+, 5), 191 (100); HRMS (CI) (M +
H)+ calcd for C13H26O4P 277.1568, obsd 277.1559.
AcOEt 1:1) to yield acid 9 (0.127 g, 86%): n22 ) 1.4695; Rf )
D
0.27 (hexane/AcOEt 1:1); 1H NMR δ 2.34 (t, J ) 7.4, 2H), 2.26-
196 (m, 2H), 1.89-1.15 (m, 24H), 0.89 (t, J ) 6.7, 3H); 13C
NMR (CDCl3, 50 MHz) δ 221.73, 179.83, 54.90, 41.40, 37.74,
34.62, 33.90, 31.70, 29.40, 29.36, 28.72, 27.79, 26.93, 26.90,
26.50, 24.47, 22.50, 13.96; MS (15 eV) m/e (%) 296 (M+, 3), 83
(100); HRMS (CI) (M + H)+ calcd for C18H33O3 297.2430, obsd
297.2438.
Meth yl 5-F or m ylp en ta n eca r boxyla te (6). To a stirred
solution of bis(triphenylphosphine)tetrahydroboratocopper(I)
[(Ph3P)2CuBH4] (26.8 g, 0.044 mol) and triphenylphosphine
(21.2 g, 0.081 mol) in acetone (130 mL) was added dropwise
solution of methyl 5-(chloroformyl)pentanecarboxylate (7.0 g,
0.036 mol) in acetone (50 mL). After 2 h the mixture was
filtered and concentrated in vacuo and 50 mL of ethyl ether
added. The mixture was filtered once again and concentrated,
and the residue was distilled under reduced pressure (bp 68-9
°C/0.1 mmHg) affording aldehyde 6 (5.2 g, 90%) as a colorless
2-Hexyl-5-h yd r oxycyclop en ta n eh ep ta n oic Acid (1). To
a stirred solution of 2-hexyl-5-oxocyclopentaneheptanoic acid
9 (0.080 g, 0.27 mmol) and sodium hydroxide (0.021 g, 0.54
mmol) in methanol (0.8 mL) at -10 °C was added sodium
borohydride (0.011 g, 0.27 mmol). After 3 h at 0 °C, the solvent
was evaporated in vacuo and the residue dissolved in 0.5 mL
of water. The solution was acidified by addition of 5% aqueous
HCl and extracted with chloroform. Organic extracts were
dried over Na2SO4, concentrated under reduced pressure, and
chromatographed on silica gel (ethyl acetate/hexane 1:1)
affording 1 (0.076 g, 95%) as a mixture of trans-trans and
trans-cis isomers: Rf ) 0.18 and 0.23 (petroleum ether/Et2O/
liquid: n21 ) 1.4341; Rf ) 0.60 (hexane/AcOEt 1:1); 1H NMR
D
δ 9.28 (t, J ) 1.5, 1H), 3.36 (s, 3H), 2.00 (t, J ) 7.4, 2H), 1.75
(dt, J ) 7.2, J ) 1.4, 2H), 1.37 (qw, J ) 7.5, 2H), 1.27-1.12
(m, 2H), 1.03-0.84 (m, 2H); 13C NMR δ 202.0, 174.0, 51.7, 44.2,
34.4, 29.4, 25.5, 22.5; MS (15 eV) m/e (%) 159 (M+ + 1, 2), 55
(100). Anal. Calcd for C8H14O3: C, 60.74; H, 8.92. Found:
C, 60.70; H, 8.87.
1
Meth yl 9-Oxo-19,20-bisn or -7-pr osten oate (7). To a stirred
solution of 2-dimethoxyphosphoryl-3-hexylcyclopentan-1-one
5 (2.5 g, 9.0 mmol) and aldehyde 6 (1.56 g, 9.9 mmol) in
AcOH 8:8:0.1); H NMR δ 4.19-4.10 (m, 1H), 3.92-3.80 (m,
1H), 2.18 (t, J ) 7.3, 4H), 2.10-1.96 (m, 1H), 1.82-0.85 (m,
51H), 0.93 (t, J ) 6.6, 6H); 13C NMR δ 180.13, 79.93, 75.13,