5080
5. Attempted formation of homogynolide-A (2) from 1 with dicyclohexylcarbodiimide and 4-dimethyiaminopyridine in
toluene at 60 °C gave only (NMR) the t~ate ester.
6. Kubo, A.; Nakahara, S.; Inaba, K.; Kitahara, Y. Chem. Pharm. Bull. 1985, 33, 2582-2584. Dev, V.; Bottini, A. T. J. Nat.
Prod. 1987, 50, 968-971.
7. For relevant studies of the problem of Z-- E tsomerization during esterification, see: Roush, W. R.; Blizzard, T .A.J.
Org. Chem. 1984, 49, 1772-1783 and 4332-4339.
8. See: Inanaga, J.; Hirat¢ K.; Seeld, H.; Katsuki, T.; Yamaguchi, M. Bull. Chem.Soc. Jpn. 1979, 52, 1989-1993. 2,4,6-
Trichiorobenzoyl chloride is available from the Aldrich Chemical Company.
9. The mixed anhydride formed with trifluoroacetic anhydride has recendy been reported to convert (E)-2-methyi-2-
butenol to its angeiate ester in only 21% yield. See: ROcker,G.; Mayer, R.; Lee, K. R. Arch. Pharm. 1989, 322, 821-826.
10. Buckles, R. E.; Mock, G. V. J. Org. Chem. 1950, 15, 680-684.
11. In cases where the angelate had an Rf value similar to that of anhydride 6, ~e crude material was stirred for 2 h in 1:1
water-pyrldine (1 mL) and then extractively isolated, prior to chromatographic purification.
12. Homogynolide-A (2), Prepared in 97 % yield by reaction at 70 °C for 16 h. 1H NMR 5 0.90 (d, J=6.9 Hz, 3H), 1.02
(s, 3H), 1.45-2.00 (m, 7H), 1.85 (dq, J=1.1, 1.4 Hz, 3H), 1.99 (dq, J=1.4, 6.6 Hz, 3H), 2.10 (dd, J=5.8, 12.0 Hz, 1H), 2.25-
2.40 (m, 1H), 2.40-2.50 (m, 1H), 4.77 (m, 2H), 5.02 (s, 1H), 5.09 (s, 1H), 5.17 (m, 1H), 6.05 (qq, J=1.1, 6.6 Hz, 1H); 13C
NMR 5 15.7 (CH3), 15.9 (CH3), 18.8 (CH3), 20.8 (CH3), 27.4 (CH2), 28.7 (CH), 34.2 (CH2), 43.6 (C), 44.6 (CH), 44.7
(CH2), 48.8 (CH2), 49.8 ((3), 69.6 (CH), 70.3 (CH2), 105.5 (CH2), 127.9 (C), 138.1 (CH), 150.5 (C), 167.1 (C), 182.5 (C);
IR 1780, 1710, 1670, 1645 cm'l; mass spectrum (CI), mle 350 (MH++ammonia, 100%), 333 (MH+), 250, 233, 122, 110.
Anal. Calcd for C20H2804: Mr , 332.1988. Found: Mr (mass spectrum), 332.1985. (Z)-(1.Methoxycarbonyl-3-
butynyl) 2-Methyl-2-butenoate (4). 2a Prepared in 80% yield by reaction at 80 °C for 20 h. 1H NMR 5 1.92 (t,
J=5.6 Hz, 1H), 1.95 (s, 3H), 2.03 (d, J=7.0 Hz, 3H), 2.82 (rid, J--5.8, 6.0 Hz, 2H), 3.79 (s, 3H), 5.26 (t, J--6.0 Hz, 1H), 6.17
(q, J=7.0 Hz, 1H); 13C NMR 5 15.9 (CH3), 20.3 (CH3), 21.7 (CH2), 52.5 (CH3), 70.0 (CH), 71.1 (C), 78.1 (CH), 126.9 (C),
139.6 (CH), 166.9 (C), 169.1 (C); IR 3300, 2950, 2130, 1770, 1730, 1645, 1140, 840 cm'l; mass spectTum (CI), m/e 228
(MH++ammonia), 211 (MH+), 124 (100%), 110, 83.t(Z)-[(1S, 2R,
5S)-2-1sopropyl-5-methylcyclohexyl]
2-
Methyl-2-butenoate (10). Prepared in 95 % yte~ by reaction at 70 °C for 20 h. [c(]20D - 84.6° (c 1, CHCI3); 1H NMR 5
0.75 (d, J--6.9 Hz, 3H), 0.68 (d, J=7.1 Hz, 3H), 0.89 (d, J=6.5 Hz, 3H), 1.00-1.80 (m, 9H), 1.86 (dq, J=1.3, 1.4 Hz, 3H),
1.94 (dq, J=1.3, 7.5 Hz, 3H), 4.75 (td, J=4.1, 11.0 Hz, 1H), 5.98 (qq, J=1.4, 7.5 Hz, 1H); 13C NMR ~> 15.6 (CH3), 16.2
(CH3), 20.6 (CH3), 20.8 (CH3), 22.0 (CH3), 23.4 (CH2), 26.3 (CH), 31.4 (CH), 34.3 (CH2), 41.1 (CH2), 47.1 (CH), 73.8
(CH), 128.5 (C), 136.6 (CH), 167.7 (C); IR 2950, 1715, 1650, 1230, 1160 cm'l; mass spectrum (CI), m/e 256
(MH++ammonia), 239, 139, 124 (100%), 110, 83, 75. Anal. Cald for C15H2602: C, 75.58; H, 11.00. Found: C, 75.43;
H, 11.05. Angelate Ester of 5ct-Androstan-17~-ol~3-one (14). Prepared in 91% yield by reaction at 70 °C for
23 h. Mp 103-105 °C (hexane); [a]20D + 45.0° (c 0.5, CHCI3); 1H NMR 5 0.70-2.40 (m, 22H), 0.85 (s, 3H), 1.02 (s, 3H),
1.89 (dq, J=1.3, 1.4 Hz, 3H), 1.98 (dq, J=1.3, 7.0 Hz, 3H), 4.66 (t, J=7.5 Hz, 1H), 6.04 (qq, J=1.4, 7.0 Hz, 1H); 13C NMR
11.4 (CH3), 12.4 (CH3), 15.7 (CH3), 20.6 (CH3), 20.8 (CH2), 23.5 (CH2), 27.7 (CH2), 28.7 (CH2), 31.1 (CH2), 35.1 (CH),
35.6 (C), 36.9 (CH2), 38.0 (CH2), 38.4 (CH2), 42.7 (C), 44.5 (CH2), 46.5 (CH), 50.5 (CH), 53~7 (CH), 82.6 (CH), 128.2 (C),
137.1 (CH), 168.0 (C), 211.7 (C); IR 1725, 1710, 1230, 1160 cm'l; mass spectrum (CI), role 390 (MH ++ammonia, 100o/O),
373 (MH+), 290, 273, 83. (Z)-[(E)-3-Phenyl-2-propenyl] 2-Methyl-2-butenoste (16). Prepared in 92 % yield
by reaction at 70 °C for 19 h. 1H NMR 5 1.92 (dq, J=1.3, 1.4 Hz, 3H), 2.00 (dq, J=1.3, 7.4 Hz, 3H), 4.81 (d, J=6.2 Hz, 2H),
6.09 (qq, J=1.3, 7.4 Hz, 1H), 6.33 (tit, J=6.2, 15.8 Hz, 1H), 6.68 (d, J=15.8 Hz, 1H), 7.20-7.50 (m, 5H); 13C NMR 5 15.7,
(CH3), 20.5 (CH3), 64.6 (CH2), 123.5 (CH), 126.5 (CH), 127.8 (C), 128.2 (CH), 128.5 (CH), 133.8 (CH), 136.3 (C), 138.0~
(CH), 167.7 (C); IR 3080, 3050, 3010, 2950, 1720, 1650, 1440, 1220 cfn'l; mass spectrum (El), m/e 216 (M+), 117, 83,
55 (100%), 28. (Z)-(2-Naphthyl) 2-Methyl-2-butenoate (18). Prepared in 96 % yield by reaction at 70 °C for 36
h. 1H NMR 52.07-2.15 (m, 3H), 2.10 (s, 3H), 6.29 (m, 1H), 7.26 (dd, J=2.7, 8.9 Hz, 1H), 7.45-7.55 (m, 2H), 7.59 (d, J=2.1
Hz, 1H), 7.75-7.95 (m, 3H); 13C NMR 5 18.0 (CH3), 20.7 (CH3), 118.6 (CH), 121.4 (CH), 125.6 (CH), 128.5 (CH), 127.3
(C), 127.6 (CH), 127.7 (CH), 129.3 (CH), 131.4 (C), 133.8 (C), 140.7 (CH), 148.4 (C), 166.3 (C); IR 3100, 2930, 2920,
1730, 1650, 1630, 1600, 1510, 1120 cm'l; mass spectrum (El), m/e 226 (M+), 144, 115, 83, 55 (100%) .(Z)-(1-
Methylcyclohexyl) 2-Methyl-2-butenoate (20). Prepared in 65 % yield by reaction at 80 °C for 20 h. 1H NMR 5
1.20-1.60 (m, 10H); 1.52 (s, 3H), 1.88 (s, 3H), 1.95 (d, J=6.8 Hz, 3H), 5.55 (q, J=6.8 Hz, 1H); 13(3 NMR 5 15.5 (CH3), 20.9
(CH3), 22.1 (CH2), 25.4 (CH2), 25.7 (CH3), 36.8 (CH2), 81.8 (C), 129.7 (C), 135.5 (CH), 167.4 (C); IR 2985, 2850, 1720,
1640, 1140, 840 cm"1 .
(Received in France 3 July 1991)