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M. Yoshida et al. / Tetrahedron 66 (2010) 2675–2682
m), 2.42–2.43 (1H, d, J¼2.4 Hz), 2.48–2.64 (4H, m), 4.43 (1H, d,
J¼2.4 Hz), 7.23–7.26 (2H, m), 7.27–7.30 (3H, m); 13C NMR (100 MHz,
(CH), 126.2 (CH), 128.8 (CH), 129.1 (CH), 131.1 (Cq), 134.0 (Cq), 135.1
(Cq), 148.2 (Cq), 158.8 (Cq), 210.4 (Cq); HRMS (ESI) m/z calcd for
CDCl3)
d
16.9 (CH2), 18.9 (CH3), 39.2 (CH2), 39.4 (CH2), 44.0 (CH),
C
20H18O2Na [MþNa]þ 313.1204, found 313.1195.
67.7 (Cq), 74.1 (CH), 81.6 (Cq), 128.0 (CH), 128.3 (CH), 129.1 (CH),
135.8 (Cq), 208.6 (Cq), 208.8 (Cq); HRMS (ESI) m/z calcd for
C16H16O2Na [MþNa]þ 263.1048, found 263.1053.
4.4.8. (2R*,3aS*)-3a-Methyl-3-methylene-2-(naphthalen-2-yl)-
3,3a,5,6-tetrahydrobenzofuran-4(2H)-one (4ca). Colorless needles;
mp 86.3–87.9 ꢀC (recrystallized from benzene); IR (neat) 2970,
4.4.3. 2-Methyl-2-(3-phenylpropa-1,2-dienyl)cyclohexane-1,3-dione
1709, 1342, 1090, 1038, 912, 872, 795 cmꢁ1 1H NMR (400 MHz,
;
(7aa). Pale yellow oil; IR (neat) 2933, 2924, 1948, 1697, 1384 cmꢁ1
;
CDCl3) d 1.57 (3H, s), 2.38–2.44 (2H, m), 2.52–2.55 (1H, m), 2.64–
1H NMR (400 MHz, CDCl3)
d
1.44 (3H, s), 1.74–1.86 (1H, m), 2.08–
2.69 (1H, m), 4.72 (1H, d, J¼2.0 Hz), 5.24 (1H, dd, J¼2.4 and 7.6 Hz),
5.70 (1H, d, J¼2.0 Hz), 5.90 (1H, t, J¼2.0 Hz), 7.29 (1H, dd, J¼2.0 and
8.8 Hz), 7.47–7.51 (2H, m), 7.74 (1H, s), 7.80–7.85 (3H, m); 13C NMR
2.17 (1H, m), 2.55–2.65 (2H, m), 2.80–2.93 (2H, m), 5.65 (1H, d,
J¼6.4 Hz), 6.39 (1H, d, J¼6.4 Hz), 7.22–7.27 (2H, m), 7.31–7.37 (3H,
m); 13C NMR (100 MHz, CDCl3)
d
17.7 (CH3 and CH2), 37.9 (CH2), 38.0
(100 MHz, CDCl3) d 19.6 (CH2), 25.5 (CH3), 37.8 (CH2), 53.3 (Cq), 83.9
(CH2), 66.5 (Cq), 97.4 (CH), 98.9 (CH), 127.0 (CH2ꢂ2), 127.9 (CH),
128.9 (CH2ꢂ2), 132.6 (Cq), 204.8 (Cq), 206.8 (Cq), 206.9 (Cq); HRMS
(ESI) m/z calcd for C16H16O2Na [MþNa]þ 263.1048, found 263.1051.
(CH), 92.8 (CH), 110.6 (CH2), 124.7 (CH), 126.3 (CHꢂ2), 126.9 (CH),
127.7 (CH), 128.0 (CH), 128.6 (CH), 133.0 (Cq), 133.3 (Cq), 137.3 (Cq),
149.2 (Cq), 159.0 (Cq), 210.5 (Cq); HRMS (ESI) m/z calcd for
C20H18O2Na [MþNaþ]þ 313.1204, found 313.1198.
4.4.4. (2R
*
,3aS )-3-Methylene-2-phenyl-3a-propyl-3,3a,5,6-tetra-
*
hydrobenzofuran-4(2H)-one (4ab). White solid; mp 67.8–69.4 ꢀC
4.5. X-ray crystallograohic analysis of compound 4ca7
(recrystallized from hexane); IR (neat) 2958, 1713, 1455, 1343, 1153,
1107, 964, 698 cmꢁ1
J¼7.2 Hz), 1.39–1.46 (2H, m), 1.69–1.77 (1H, m), 1.89–1.96 (1H, m),
2.31–2.40 (2H, m), 2.48–2.62 (2H, m), 4.75 (1H, d, J¼1.6 Hz), 5.25–
527 (1H, m), 5.63 (2H, s), 7.22–7.24 (2H, m), 7.27–7.36 (3H, m); 13C
;
1H NMR (400 MHz, CDCl3)
d
0.92 (3H, t,
A colorless platelet crystal of C20H18O2 having approximate di-
mensions of 0.80ꢂ0.80ꢂ0.30 mm was mounted on a glass fiber. All
measurementsweremadeon aRigaku RAXISRAPIDimagingplatearea
detector with graphite monochromated Mo Karadiation. The structure
NMR (100 MHz, CDCl3)
d
14.1(CH3), 18.2 (CH2), 19.7 (CH2), 37.6
was solved by direct methods (SIR97) and expanded using Fourier
techniques (DIRDIF99). The non-hydrogen atoms were refined aniso-
tropically. Hydrogen atoms were refined using the riding model. The
final cycle of full-matrix least-squares refinement on F was based on
(CH2), 41.0 (CH2), 58.1 (Cq), 84.1 (CH), 93.7 (CH), 110.9 (CH2), 127.3
(CH), 128.3 (CH), 128.5 (CH), 140.5 (Cq), 148.0 (Cq), 158.0 (Cq), 210.0
(Cq); HRMS (ESI) m/z calcd for C18H20O2Na [MþNa]þ 291.1361,
found 291.1367.
7617 observed reflections (I>0.00s(I)) and218 variable parameters and
converged (largest parameter shift was 0.00 times its esd) with un-
weighted and weighted agreement factors of R¼0.054 and Rw¼0.158.
Crystal data for 4ca: C20H18O2, M¼290.36, orthorhombic, space group
P212121, a¼9.086(5) Å, b¼9.040(5) Å, c¼18.67(1) Å, V¼1533(1) Å3,
4.4.5. (2R
hydrobenzofuran-4(2H)-one (4ac). Pale yellow oil; IR (neat) 3029,
1709, 1494, 1454, 1384, 1137, 767, 700 cmꢁ1 1H NMR (400 MHz,
CDCl3) 1.49–1.59 (1H, m), 2.02–2.09 (1H, m), 2.21–2.30 (1H, m),
*
,3aS
*
)-3a-Benzyl-3-methylene-2-phenyl-3,3a,5,6-tetra-
;
d
Z¼4, Dc¼1.257 g/cm3, F(000)¼616.00,
m
(Mo K
a
)¼0.80 cmꢁ3
.
2.34–2.40 (1H, m), 2.94 (1H, d, J¼12.8 Hz), 3.32 (1H, d, J¼12.8 Hz),
4.73 (1H, d, J¼2.4 Hz), 5.27–5.30 (2H, m), 5.68 (1H, d, J¼2.8 Hz),
7.17–7.23 (4H, m), 7.27–7.34 (6H, m); 13C NMR (100 MHz, CDCl3)
4.5.1. (2S
tetrahydrobenzofuran-4(2H)-one (4da). Pale yellow oil; IR (neat)
2927, 1718, 1501, 1157, 784, 608 cmꢁ1 1H NMR (400 MHz, CDCl3)
1.45 (3H, s), 2.29–2.34 (2H, m), 2.45–2.54 (1H, m), 2.56–2.66 (1H,
*
,3aS )-2-(Furan-3-yl)-3a-methyl-3-methylene-3,3a,5,6-
*
d
18.8 (CH2), 38.7 (CH2), 45.0 (CH2), 59.6 (Cq), 83.7 (CH), 95.9 (CH),
;
110.7 (CH2),127.2 (CH),127.2 (CH),128.1(CH),128.3 (CH),128.4 (CH),
130.3 (CH), 135.7 (Cq), 140.4 (Cq), 148.3 (Cq), 156.4 (Cq), 210.7 (Cq);
HRMS (ESI) m/z calcd for C22H21O2 [MþH]þ 317.1542, found
317.1544.
d
m), 4.94 (1H, d, J¼2.4 Hz), 5.13–5.16 (1H, m), 5.69 (1H, d, J¼2.4 Hz),
5.77 (1H, t, J¼2.4 Hz), 6.27 (1H, s), 7.38 (1H, s), 7.44 (1H, s); 13C NMR
(100 MHz, CDCl3) d 19.5 (CH3), 25.3 (CH), 37.4 (CH2), 53.1 (Cq), 76.2
(CH), 93.2 (Cq), 109.0 (CH), 110.0 (CH2), 124.2 (Cq), 141.4 (CH), 143.8
(CH), 147.8 (Cq), 158.2 (Cq), 210.3 (Cq); HRMS (ESI) m/z calcd for
C14H15O3 [MþH]þ 231.1021, found 231.1017.
4.4.6. (2R
*
,3aS )-3a-(2-cyanoethyl)-3-methylene-2-phenyl-3,3a,5,6-
*
tetrahydrobenzofuran-4(2H)-one (4ad). Colorless plates; mp 102.8–
103.4 ꢀC (recrystallized from benzene); IR (neat) 3398, 2243, 1707,
1693, 1600, 1494, 1452, 1149, 1009, 928 cmꢁ1
;
1H NMR (400 MHz,
4.5.2. (2R
drobenzofuran-4(2H)-one (4ea). Pale yellow oil; IR (neat) 3458,
2930,1717,1384,1089 cmꢁ1; 1H NMR (400 MHz, CDCl3)
0.88 (3H, t,
*
,3aS
*
)-3a-Methyl-3-methylene-2-pentyl-3,3a,5,6-tetrahy-
CDCl3)
d 2.08–2.15 (1H, m), 2.22–2.30 (1H, m), 2.37–2.51 (5H, m),
2.61–2.66 (1H, m), 4.87 (1H, d, J¼2.0 Hz), 5.36–5.38 (1H, dd, J¼2.8
d
and 7.6 Hz), 5.65–5.67 (2H, m), 7.21–7.22 (2H, m), 7.33–7.37 (3H,
J¼7.6 Hz),1.26–1.32 (5H, m),1.41 (3H, s),1.43–1.50 (2H, m),1.67–1.69
(1H, m), 2.24–2.34 (2H, m), 2.42–2.51 (1H, m), 2.54–2.60 (1H, m),
4.79–4.83 (1H, m), 4.98 (1H, d, J¼2.4 Hz), 5.07–5.10 (1H, m), 5.57 (1H,
m); 13C NMR (100 MHz, CDCl3)
d 13.0 (CH2), 19.4 (CH2), 32.0 (CH2),
37.8 (CH2), 56.0 (Cq), 83.8 (CH), 95.5 (CH), 112.9 (CH2), 118.7 (Cq),
127.1 (CH), 128.6 (CHꢂ2), 139.7 (Cq), 145.8 (Cq), 156.4 (Cq), 208.5
(Cq); HRMS (ESI) m/z calcd for C18H17NO2Na [MþNa]þ 302.1157,
found 302.1158.
d, J¼2.4 Hz); 13C NMR (100 MHz, CDCl3)
d 14.0 (CH3),19.5 (CH2), 22.5
(CH2), 25.7 (CH3), 31.7 (CH2), 34.8 (CH2), 37.5 (CH2), 53.4 (Cq), 81.7
(CH), 92.4 (CH), 107.3 (CH2), 149.1 (Cq), 158.6 (Cq), 210.8 (Cq); HRMS
(ESI) m/z calcd for C15H23O2 [MþH]þ 235.1698, found 235.1698.
4.4.7. (2S
*
,3aS )-3a-Methyl-3-methylene-2-(naphthalen-1-yl)-
*
3,3a,5,6-tetrahydrobenzofuran-4(2H)-one (4ba). Colorless crystals;
4.5.3. (2R
*
,3aS )-2-(3,4-Dimethoxyphenyl)-3a-methyl-3-methylene-
*
mp 129.3–132.6 ꢀC (recrystallized from benzene); IR (neat) 2927,
3,3a,5,6-tetrahydrobenzofuran-4(2H)-one (4ga). Pale yellow oil; IR
1709, 1385, 1341, 1157, 1092, 1038, 786 cmꢁ1
;
1H NMR (400 MHz,
(neat) 2936, 1714, 1594, 1517, 1463, 1261, 1164, 1027 cmꢁ1; 1H NMR
CDCl3)
d
1.62 (3H, s), 2.36–2.47 (2H, m), 2.50–2.59 (1H, m), 2.61–
(400 MHz, CDCl3) d 1.49 (3H, s), 2.32–2.41 (2H, m), 2.48–2.57 (1H,
2.70 (1H, m), 4.74 (1H, d, J¼2.8 Hz), 5.23–5.25 (1H, m), 5.66 (1H, d,
J¼2.8 Hz), 6.49 (1H, s), 7.41–7.46 (2H, m), 7.47–7.51 (2H, m), 7.81–
7.84 (1H, m), 7.84–7.88 (1H, m), 7.92–7.95 (1H, m); 13C NMR
m), 2.60–2.69 (1H, m), 3.85 (3H, s), 3.87 (3H, s), 4.76 (1H, d,
J¼1.6 Hz), 5.17–5.19 (1H, m), 5.69–5.71 (2H, m), 6.73 (1H, s), 6.83
(2H, s); 13C NMR (100 MHz, CDCl3)
d 19.5 (CH2), 25.3 (CH3), 37.6
(100 MHz, CDCl3)
(CH), 93.3 (CH), 110.2 (CH2),124.0 (CH), 125.2 (CH),125.7 (CH),125.7
d
19.6 (CH2), 25.5 (CH3), 37.8 (CH2), 53.6 (Cq), 81.7
(CH2), 53.3 (Cq), 55.8 (CH3), 55.8 (CH3), 83.7 (CH), 92.5 (CH), 110.3
(CH2), 110.4 (CH), 110.8 (CH), 120.3 (CH), 132.2 (Cq), 149.0 (Cq), 149.1