3
3
13
3 2 3 3
s, СН ); 1.78 and 1.65 (each 1H, m, CH in ring); 1.22 (3Н, t, J = 6.8, СН ); 1.18 (3Н, t, J = 6.8, СН ). C
NMR spectrum, δ, ppm: 201.3; 168.1; 165.2; 62.4; 59.8; 42.7 (quaternary carbon); 28.3; 20.1; 18.7; 14.1; 13.9.
Found, %: С 57.65; Н 7.36. С Н О . Calculated, %: С 57.89; Н 7.07.
1
1
16
5
1
,1-Diacetyl-2-ethoxycarbonylcyclopropane (8). This compound was obtained from a mixture of
acetylacetone (5 g, 0.05 mol), ethyl 2,3-dibromopropionate (13 g, 0.05 mol), and K CO (22 g, 0.16 mol) with a
2
3
2
0
1
yield of 4.5 g (45.5%); bp 120-121°C (1 mm Hg), nD 1.4635. H NMR spectrum, δ, ppm (J, Hz): 4.05 (2Н, q,
О); 2.61 (1Н, m, СН); 2.17 (3Н, s, СН ); 2.15 (3Н, s, СН ); 1.82 and 1.73 (each 1H, m, CH in
2 3 3 2
ring); 1.2 (3Н, t, J = 6.8, СН ). C NMR spectrum, δ, ppm: 203.5; 203.4; 170.1; 61.8; 49.9; 30.2; 30.1; 27.8;
3
J = 6.8, СН
3
13
3
1
9.2; 14.9. Found, %: С 60.27; Н 7.33. С Н О . Calculated, %: С 60.59; Н 7.2.
10 14 4
6
,6-Dimethyl-2-vinyl-2,3,4,5,6,7-hexahydrobenzo[b]furan-4-one (9). From a mixture of dimedone
(
14 g, 0.1 mol), 1,4-dibromo-2-butene (21.3 g, 0.1 mol), and K CO (27.6 g, 0.2 mol) in DMSO (150 ml) we
2
3
2
0
1
obtained 10 g (52%) of compound 9; bp 115-115.5°C (1 mm Hg), n 1.5000. H NMR spectrum, δ, ppm (J,
Hz): 5.85 (1Н, m, СН=); 5.26 and 5.15 (each 2Н, d, J = 10.1, J
and 2.50 (each 1Н, dd, J = 14.7, J = 9.5, СН in ring); 2.22 and 2.13 (each 2Н, s, СН in dimedone ring); 1.13
(
D
3
3
cis
trans
2
= 16.9, СН =); 5.21 (1H, m, CHO); 2.93
2
3
2
2
1
3
6Н, s, 2СН ). C NMR spectrum, δ, ppm: 194.9; 177.1; 137.6; 117.8; 106.3; 86.3; 52.1; 43.3; 38.2; 32.7; 27.4.
3
Found, %: С 74.73; Н 8.39. С Н О . Calculated, %: C 74.97; Н 8.39.
1
2
16
2
4
-Acetyl-5-methyl-2-vinyl-2,3-dihydrofuran (10). From a mixture of acetylacetone (10 g, 0.1 mol),
1
,4-dibromo-2-butene (21.3 g, 0.1 mol), and K CO (42 g, 0.3 mol) in DMSO (70 ml) we obtained 12 g (79%)
2
3
2
0
1
of compound 10; bp 80-80.5°C (1 mm Hg), n 1.4970. H NMR spectrum, δ, ppm (J, Hz): 6.0 (1Н, m, СН=);
D
3
3
5
.39 and 5.29 (each 2Н, d, J = 10.36, J
trans 2
= 16.82, СН =); 5.1 (1Н, m, ОСН); 3.20 and 2.79 (each 1Н, dd,
cis
2
3
13
J = 16.6, J = 8.9, СН
2 3
in ring); 2.30 and 2.19 (each 3Н, s, СН ). C NMR spectrum, δ, ppm: 192.8; 166.8;
1
37.9; 117.5; 111.2; 83.1; 36.9; 28.4; 14.99. Found, %: С 70.83; Н 8.16. С Н О . Calculated, %: С 71.03;
9
12
2
Н 7.95.
4
-(2-Hydroxybut-3-enyl)-3,5-dimethylisoxazole (11). To 40 ml of a 10% solution of sodium acetate we
added of compound 10 (1.56 g, 0.010 mol) and hydroxylamine hydrochloride (0.69 g, 0.010 mol). The mixture
was stirred at 50°C for 5 h, cooled, and extracted with ether. The extracts were washed with water and dried
with anhydrous MgSO . The residue after distillation of the ether was distilled under vacuum. We obtained 0.86
4
2
0
1
g (52%) of compound 11; bp 132-134°C (0.1 mm Hg), n 1.4940. H NMR spectrum, δ, ppm (J, Hz): 5.82
1Н, m, СН=); 5.20 and 5.08 (2Н, dd, J = 10.2, J
ОСН); 2.48 (2Н, d, J = 9.5, СН ); 2.33 and 2.15 (each 3Н, s, СН ). C NMR spectrum, δ, ppm: 166.3; 159.6;
D
3
3
3
(
= 16.9; СН =); 4.30 (1Н, s, ОН); 4.14 (1Н, q, J = 7.8,
cis
trans
2
3
13
2
3
1
40.7; 114.8; 110.1; 73.4; 31.4; 12.3; 11.2. Found, %: С 64.87; Н 7.62; N 87.56. С Н NО . Calculated, %:
9 13 2
С 64.65; Н 7.84; N 8.38.
4
-(2-Acetoxybut-3-enyl)-3,5-dimethylisoxazole (12). To a solution of compound 11 (2 g, 0.012 mol) in
CCl (10 ml) we added acetyl chloride (1 g, 0.0127 mol). The mixture was shaken carefully on a water bath
4
(
80°C) and left until the morning. The residue after distillation of the CCl was distilled under vacuum. We
4
2
0
1
obtained 1.8 g (71.4%) of compound 12; bp 165-166.5°C (1 mm Hg), n 1.4791. H NMR spectrum, δ, ppm
D
3
3
(
J, Hz): 5.85 (1Н, m, СН=); 5.2 (2Н, dd, J = 10.3, J
trans 2
= 16.7, СН =); 5.13 (1Н, m, СНО); 2.63 (2Н, d,
cis
3
13
J = 9.2, СН
2 3 3
); 2.29 and 2.15 (each 3Н, s, СН ); 2.00 (3Н, s, СН С=О). C NMR spectrum, δ, ppm: 169.8;
1
67.6; 159.8; 138.4; 117.7; 109.8; 74.3; 26.9; 21.4; 10.2; 10.1. Found, %: С 63.48; Н 7.04; N 6.46. С Н NО .
1
1
15
3
Calculated, %: С 60.3; Н 6.84; N 6.39.
REFERENCES
1
2
.
.
V. Nair, J. Mathew, and J. Prabhakaran, Chem. Soc. Rev., 26, 127 (1997).
X. L. Hou, H. Y. Cheung Hon, T. Y. Kwan, T. H. Lo, S. Y. Tong, and H. N. Wong, Tetrahedron, 54,
955 (1998).
T. L. Gilchrist, J. Chem. Soc., Perkin Trans. 1, 2849 (1999).
1
3
.
4
03