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K. V. Babu, G. V. M. Sharma / Tetrahedron: Asymmetry 19 (2008) 577–583
4.1.12.
(1R,8S)-8-(Methoxymethoxy)-1-methyl-9-decenyl
2919, 2845, 1718 cmꢀ1; HRMS m/z [MꢀH]+ found
acrylate 21. A solution of DIPEA (0.295 g, 2.28 mmol)
and 20 (0.175 g, 0.761 mmol) in CH2Cl2 (4 mL) at 0 °C
was treated with acryloyl chloride (0.10 g, 1.14 mmol)
and stirred at room temperature for 3 h. The reaction mix-
ture was evaporated under reduced pressure and the resi-
due purified by column chromatography (silica gel,
EtOAc/hexane, 4:96) to afford 21 (0.199 g, 93%) as a yellow
syrup. ½aꢁD ¼ ꢀ122:5 (c 0.25, CHCl3); H NMR (CDCl3,
300 MHz): d 1.25 (d, 3H, J = 6.2 Hz, –CH3), 1.30–1.67
(m, 12H, 6 ꢂ –CH2), 3.33 (s, 3H, –OCH3), 3.94 (q, 1H,
J = 6.6 Hz, –OCH), 4.47 (d, 1H, J = 6.6 Hz, –OCH), 4.66
(d, 1H, J = 6.6 Hz, –OCH), 4.96 (sextet, 1H, J = 6.2 Hz,
–OCH), 5.12–5.20 (m, 2H, olefinic), 5.53–5.72 (m, 1H, ole-
finic), 5.79 (dd, 1H, J = 1.8, 10.3 Hz olefinic), 5.99–6.13 (m,
1H, olefinic), 6.36 (dd, 1H, J = 1.8, 17.3 Hz olefinic); 13C
NMR (75 MHz, CDCl3): d 19.9, 25.2, 25.3, 29.4, 29.5,
35.4, 35.9, 55.4, 71.2, 77.3, 93.7, 116.9, 129.1, 130.0,
138.5, 165.8; IR (neat): 2932, 2857, 1723, 1199,
1037 cmꢀ1; HRMS m/z [M+Na]+ found 307.1883; calcu-
lated 307.1885 for C16H28O4Na.
211.1344; calculated 211.1334 for C12H19O3.
4.1.15. (2S,9S)-9-(Methoxymethoxy)-10-undecene-1,2-diol
22 and (2R)-2-[(7S)-7-(methoxymethoxy)-8-nonenyl]oxirane
8. A mixture of (R,R)-(+)-N,N0-bis(3,5-di-tert-butylsali-
cylidene)-1,2-cyclohexanediaminocobalt7 (II) (0.006 g,
0.009 mmol) in toluene (0.25 mL) and acetic acid (0.23 g,
3.86 mmol) was stirred while open to the air for 1 h at
room temperature. The reaction mixture was concentrated
under reduced pressure and the brown residue was dried
under vacuum. The racemic epoxide 9 (0.4 g, 1.75 mmol)
was added in one portion at 0 °C and water (0.018 mL,
0.97 mmol) was added. The reaction mixture was allowed
to warm to room temperature and stirred for 12 h. The res-
idue was purified by column chromatography. First eluted
(silica gel, EtOAc/hexane, 1:9) was (R)-oxirane 8 (0.172 g,
25
1
25
1
43%) as a yellow syrup ½aꢁD ¼ ꢀ23:3 (c 0.25, CHCl3); H
NMR (CDCl3, 300 MHz): d 1.33–1.59 (m, 12H, 6 ꢂ
–CH2), 2.41 (dd, 1H, J = 2.6, 5.1 Hz, –OCH), 2.67–2.71
(m, 1H, –OCH), 2.80–2.86 (m, 1H, –OCH), 3.34 (s, 3H,
–OCH3), 3.94 (q, 1H, J = 7.2 Hz, –OCH), 4.47 (d, 1H,
J = 6.6 Hz, –OCH), 4.66 (d, 1H, J = 6.6 Hz, –OCH),
5.13–5.19 (m, 2H, olefinic), 5.57–5.68 (m, 1H, olefinic);
IR (neat): 2926, 2854, 1461, 1036 cmꢀ1; HRMS m/z
[M+Na]+ found 251.1616; calculated 251.1623 for
C13H24O3Na.
4.1.13. (1R,8S)-8-Hydroxy-1-methyl-9-decenyl acrylate
5. To a solution of 21 (0.178 g, 0.63 mmol) in n-butanol
(4 mL), PPTS (0.473 g, 1.88 mmol) was added and stirred
at reflux for 4 h. Then reaction mixture was concentrated,
residue dissolved in EtOAc (20 mL), washed with water
(2 mL), brine (2 mL) and dried (Na2SO4). Solvent was
evaporated and residue purified by column chromatogra-
phy (silica gel, EtOAc/hexane, 1:4) to afford 5 (0.125 g,
83%) as a yellow syrup. ½aꢁD ¼ þ11:5 (c 0.25, CHCl3); H
NMR (CDCl3, 300 MHz): d 1.23 (d, 3H, J = 6.4 Hz,
–CH3), 1.27–1.67 (m, 12H, 6 ꢂ –CH2), 4.05 (q, 1H,
J = 6.1 Hz, –OCH), 4.93 (sextet, 1H, J = 6.1 Hz, –OCH),
5.08 (td, 1H, J = 1.5, 10.6 Hz, olefinic), 5.18 (td, 1H,
J = 1.5, 16.9 Hz, olefinic), 5.77 (dd, 1H, J = 1.5, 10.2 Hz,
olefinic), 5.76–5.88 (m, 1H, olefinic), 6.02–6.12 (m, 1H, ole-
finic), 6.36 (dd, 1H, J = 1.5, 16.9 Hz, olefinic); 13C NMR
(75 MHz, CDCl3): d 19.9, 25.2, 25.3, 29.3, 29.4, 35.9,
36.9, 71.2, 73.2, 114.5, 129.1, 130.1, 141.3, 165.9; IR (neat):
3443, 2926, 2856, 1723, 1199 cmꢀ1; HRMS m/z [M+F]+
found 259.1717; calculated 259.1709 for C14H24O3F.
The second eluted (silica gel, EtOAc/hexane, 4:1) was diol
25
1
22 (0.189 g, 44%) ½aꢁD ¼ ꢀ29:4 (c 0.25, CHCl3); H NMR
(CDCl3, 300 MHz): d 1.23–1.59 (m, 12H, 6 ꢂ –CH2), 3.34
(s, 3H, –OCH3), 3.35–3.40 (m, 1H, –OCH), 3.59–3.66 (m,
2H, –OCH), 3.94 (q, 1H, J = 7.1 Hz, –OCH), 4.47 (d,
1H, J = 6.6 Hz, –OCH), 4.64 (d, 1H, J = 6.6 Hz, –OCH),
5.14–5.19 (m, 2H, olefinic), 5.57–5.68 (m, 1H, olefinic);
IR (neat): 3394, 2927, 2856, 1461, 1036 cmꢀ1; HRMS m/z
[M+Na]+ found 269.1721; calculated 269.1728 for
C13H26O4Na.
25
1
4.1.16. (2S,9S)-9-(Methoxymethoxy)-10-undecen-2-ol 23.
Compound 23 was prepared from 8 (0.17 g, 0.48 mmol)
following the procedure described for compound 20 in
25
89% yield as a colourless liquid. ½aꢁD ¼ ꢀ2:6 (c 0.25,
CHCl3); 1H NMR (CDCl3, 200 MHz): d 1.15 (d, 3H,
J = 6.3 Hz, –CH3), 1.23–1.67 (m, 12H, 6 ꢂ –CH2),
3.34 (s, 3H, –OCH3), 3.66–4.16 (m, 2H, 2 ꢂ –OCH), 4.48
(d, 1H, J = 6.6 Hz, –OCH), 4.66 (d, 1H, J = 6.6 Hz,
–OCH), 5.09–5.21 (m, 2H, olefinic), 5.52–5.71 (m, 1H,
olefinic); IR (neat): 3428, 2926, 2854 cmꢀ1; HRMS m/z
[M+Na]+ found 253.1774; calculated 253.1779 for
C13H26O3Na.
4.1.14. Patulolide C 1. To a solution of 5 (0.05 g,
0.208 mmol) in CH2Cl2 (125 mL), 5 mol % Grubbs catalyst
II (8.9 mg, 0.0104 mmol) was added and stirred at reflux
for 24 h under N2 atmosphere. Most of the solvent was
then distilled off and the concentrated solution left to stir
at room temperature for 2 h under air bubbling to decom-
pose the catalyst. The reaction mixture was evaporated to
dryness to give a brown residue, which was purified by col-
umn chromatography (silica gel, EtOAc/hexane, 3:7) to
4.1.17.
(1S,8S)-8-(Methoxymethoxy)-1-methyl-9-decenyl
furnish
1
as
a
colourless syrup (21 mg, 47.5%).
acrylate 24. Compound 24 was prepared from 23
(0.10 g, 0.44 mmol) following the procedure described for
25
½aꢁD ¼ þ6:0 (c 0.5, EtOH); lit.2c [a]D = +6.6 (c 0.42,
EtOH); lit.2b [a]D = +6.8 (c 0.15, EtOH); 1H NMR
(CDCl3, 300 MHz): d 1.13–1.67 (m, 12H, 6 ꢂ –CH2), 1.23
(d, 3H, J = 6.4 Hz, –CH3), 4.31 (q, 1H, J = 4.5 Hz,
–OCH), 4.99–5.05 (m, 1H, –OCH), 6.03 (dd, 1H, J = 1.5,
15.5 Hz, olefinic), 6.91 (dd, 1H, J = 4.5, 15.9 Hz, olefinic);
13C NMR (75 MHz, CDCl3): d 19.9, 23.9, 24.2, 28.1, 28.6,
34.7, 36.5, 70.9, 71.1, 120.5, 149.9, 166.6; IR (neat): 3416,
compound 21 in 91% yield as a colourless liquid.
25
½aꢁD ¼ ꢀ33:5 (c 0.25, CHCl3); 1H NMR (CDCl3,
300 MHz): d 1.22 (d, 3H, J = 6.2 Hz, –CH3), 1.26–1.74
(m, 12H, 6 ꢂ –CH2), 3.33 (s, 3H, –OCH3), 3.94 (q, 1H,
J = 6.2 Hz, –OCH), 4.40 (d, 1H, J = 6.6 Hz, –OCH),
4.62 (d, 1H, J = 6.6 Hz, –OCH), 4.93 (sextet, 1H,
J = 6.6 Hz, –OCH), 5.10–5.20 (m, 2H, olefinic), 5.53–5.71