Communications
Jensen, Acta Chem. Scand. B 1988, 42, 495 – 503; f) uriolide: P.
[29] Method: K. Miwa, T. Aoyama, T. Shioiri, Synlett 1994, 107 – 108.
[30] trans-Selective hydrostannylation of hydroxy-32 with Bu3SnH
and cat. [PdCl2(PPh3)2]: M. Kuba, N. Furuichi, S. Katsumura,
Chem. Lett. 2002, 1248 – 1249.
Foss, R. R. L. Guillard, S. Liaaen-Jensen, Phytochemistry 1986,
25, 119 – 124; g) deepoxyuriolide: E. S. Egeland, S. Liaaen-
Jensen, Phytochemistry 1995, 40, 515 – 520; h) anhydrouriolide:
ref. [6g]; i) 3’-dehydrouriolide: ref. [6g]; j) unnamed carotenoid:
T. Maoka, K. Hashimoto, N. Akimoto, Y. Fuhiwara, J. Nat. Prod.
2001, 64, 578 – 581; k) unnamed carotenoid: M. Suzuki, K.
Watanabe, S. Fujiwara, T. Kurasawa, T. Wakabayashi, M.
Tsuzuki, K. Iguchi, T. Yamori, Chem. Pharm. Bull. 2003, 724 –
727.
[31] (trans)-1-[(1S,2R)-1,2-Epoxy-2,6,6-trimethylcyclohexyl]-2-(tri-
butylstannyl)ethene (trans-31): 1H NMR (500.0 MHz, CDCl3): d
= 0.88 (t, J4’’,3’’ = 7.3 Hz, 3 ꢈ 4’’-H3), superimposed in part with
0.87–0.91 (m, 3 ꢈ 1’’-H2), 0.93, 1.09 and 1.15 [3 ꢈ s, 2’-CH3, 6’-
(CH3)2], 1.00–1.06 (m, 5’-H1), 1.30 (qt, J3’’,4’’ = J3’’,2’’ = 7.3 Hz, 3 ꢈ
3’’-H2), 1.39–1.53 ppm (m, 4’-H2, 5’-H2, 3 ꢈ 2’’-H2), AB signal (dA
= 1.72, dB = 1.87, 2JAB = 15.2 Hz, additionally split by JA,4’
= 5.7 Hz and JB,4’ = 7.9 Hz, 3’-H2), AB signal (dA = 6.151, dB
= 6.166, JAB = 19.2 Hz; accompanying Sn isotope satellites as
[7] a) F. C. Gꢃrth, A. Umland, R. Brꢁckner, Eur. J. Org. Chem.
1998, 1055 – 1062; b) review: R. Brꢁckner, J. Chem. Soc. Chem.
Commun. 2001, 141 – 152.
[8] Other approaches to g-alkylidenebutenolides: a) E.-I. Negishi,
M. Kotora, Tetrahedron 1997, 53, 6707 – 6738; b) R. Brꢁckner,
Curr. Org. Chem. 2001, 5, 679 – 718; c) R. Rossi, F. Bellina in
Targets in Heterocyclic Systems: Shemistry and Properties, Vol. 5
(Eds.: O. A. Attanasi, D. Spinelli), Societꢄ Chimica Italiana,
2002, pp. 169 – 198.
[9] a) N. Furuichi, H. Hara, T. Osaki, H. Mori, S. Katsumura,
Angew. Chem. 2002, 114, 1065 – 1068; Angew. Chem. Int. Ed.
2002, 41, 1023 – 1026; b) N. Furuichi, H. Hara, T. Osaki, M.
Takano, H. Mori, S. Katsumura, J. Org. Chem. 2004, 69, 7949 –
7959.
[10] a) Synthesis of a racemic mixture of diastereomers: M. Ito, Y.
Hirata, Y. Shibata, K. Tsukida, J. Chem. Soc. Perkin Trans. 1
1990, 197 – 199; b) synthesis of enantiomerically and diastereo-
merically pure 2: Y. Yamano, M. Ito, J. Chem. Soc. Perkin Trans.
1 1993, 1599 – 1610.
[11] K. Siegel, R. Brꢁckner, Chem. Eur. J. 1998, 4, 1116 – 1122.
[12] F. von der Ohe, R. Brꢁckner, New J. Chem. 2000, 24, 659 – 669.
[13] I. Hanisch, R. Brꢁckner, Synlett 2000, 374 – 378.
[14] M. Carmack, C. J. Kelley, J. Org. Chem. 1968, 33, 2171 – 2173.
[15] D. A. Nugiel, K. Jacobs, T. Worley, M. Patel, R. F. Kalten-
bach III, D. T. Meyer, P. K. Jadhav, G. V. De Lucca, T. E.
Smyser, R. M. Klabe, L. T. Bacheler, M. M. Rayner, S. P. Seitz,
J. Med. Chem. 1996, 39, 2156 – 2169.
3
3
2 d per signal branch: JH(A),119Sn = 70.5 Hz, JH(A),117Sn = 67.5 Hz,
2JH(B),119Sn = 74.9 Hz, 2JH(B),117Sn = 71.7 Hz; A: 1-H, B: 2-H).
[32] Stannane cis-31 was prepared as a racemic mixture from (2,6,6-
trimethyl-1-cyclohexenyl)acetylene in two steps: radical-medi-
ated hydrostannylation with Bu3SnH; epoxidation with meta-
chloroperbenzoic acid: F. v. d. Ohe, Dissertation, Universitꢉt
Freiburg, 2001.
[33] (5S)-3-Bromo-5-[(2trans,4E,1S)-1-hydroxy-5-(methoxycar-
bonyl)-2-methyl-2,4-pentadienyl]-2(5H)-furanone
(35):
1H NMR (500.0 MHz, CDCl3): d = 1.97 (d, J2’-Me,3’ = 1.2 Hz, 2’-
CH3), 2.91 (brs, OH), 3.77 (s, OCH3), 4.30 (brd, J1’,5 = 5.5 Hz, 1’-
H), 5.08 (dd, J5,1’ = 5.6 Hz, J5,4 = 1.8 Hz, 5-H), 5.94 (d, J5’,4’
= 15.2 Hz, 5’-H), 6.27 (dmc, J3’,4’ = 11.5 Hz, 3’-H), 7.44 (d, J4,5
= 1.9 Hz, 4-H), 7.55 ppm (dd, J4’,5’ = 15.4 Hz, J4’,3’ = 11.5 Hz, 4’-
H).
4
[34] V. Farina, V. Krishnamurthy, W. J. Scott, Org. React. 1997, 50, 1 –
652.
[35] Method: V. Farina, B. Krishnan, J. Am. Chem. Soc. 1991, 113,
9585 – 9595.
[36] Method: L. S. Liebeskind, R. W. Fengl, J. Org. Chem. 1990, 55,
5359 – 5364.
[37] (5S)-3-{(E)-2-[(1S,2R)-1,2-Epoxy-2,6,6-trimethylcyclohexyl]-
ethenyl}-5-[(2E,4trans,1S)-1-hydroxy-5-(methoxycarbonyl)-2-
methyl-2,4-pentadienyl]-2(5H)-furanone
(5):
1H NMR
[16] J. McNulty, V. Grunner, J. Mao, Tetrahedron Lett. 2001, 42,
5609 – 5612.
[17] O. Isler, H. Gutmann, M. Montavon, R. Rꢁegg, G. Ryser, P.
Zeller, Helv. Chim. Acta 1957, 40, 1242 – 1249.
(500.0 MHz, CDCl3): d = 0.93, 1.13 and 1.15 [3 ꢈ s, 2’’-CH3, 6’’-
(CH3)2], 1.06–1.10 (m, 5’’-H1), ca. 1.39–1.49 (m, 4’’-H1, 5’’-H2),
2
1.61–1.68 (m, 4’’-H2), AB signal (dA = 1.75, dB = 1.90, JAB
= 15.1 Hz, additionally split by
J
JA,4’’-H(1) = JA,4’’-H(2) = 5.2 Hz,
B,4’’-H(1) = JB,4’’-H(2) = 7.6 Hz, 3’’-H2), 1.99 (d, 4J2’’’-Me,3’’’ = 1.4 Hz,
[18] E. Buchta, F. Andree, Chem. Ber. 1960, 93, 1349 – 1353.
1
[19] All new compounds gave satisfactory H and 13C NMR spectra
2’’’-CH3), 2.57 (brs, OH), 3.77 (s, OCH3), 4.18 (d, J1’’’,5 = 6.2 Hz,
1’’’-H), 5.01 (mc, approximately interpretable as dd, J5,1’’’
= 6.3 Hz, J5,4 = 1.9 Hz, 5-H), 5.95 (d, J5’’’,4’’’ = 15.3 Hz, 5’’’-H),
6.28 (mc, approximately interpretable as ddq, J3’’’,4’’’ = 11.6 Hz,
4J3’’’,5’’’ ꢂ 1.4 Hz, 4J3’’’,2’’’-Me ꢂ 0.8 Hz, 3’’’-H), 6.29 (d, J1’,2’ = 15.7 Hz,
1’-H), 6.95 (d, J4,5 = 2.1 Hz, 4-H), 7.22 (d, J2’,1’ = 15.6 Hz, 2’-H),
7.57 ppm (dd, J4’’’,5’’’ = 15.1 Hz, J4’’’,3’’’ = 11.5 Hz, 4’’’-H).
and correct combustion analyses, except aldehyde 21, (hydroxy-
alkyl)butenolides 35, 4, and 5, and the unstable alkylidenebuten-
olides 36 and 37; all of these, however, provided correct high-
resolution mass spectra.
[20] The reaction of monoketone 14 and the sodium derivative of
=
ꢀ
ꢀ
(EtO)2P( O) CH2 CO2Et gave the ethyl ester/Weinreb amide
analogue of 17 as an E:Z mixture (93% yield, E:Z = 59:41).
[21] W. C. Still, M. Kahn, A. Mitra, J. Org. Chem. 1978, 43, 2923 –
2925.
[38] (5Z)-3-{(E)-2-[(1S,2R)-1,2-Epoxy-2,6,6-trimethylcyclohexyl]-
ethenyl}-5-[(2E,4trans)-5-(methoxycarbonyl)-2-methyl-2,4-pen-
tadienylidene]-2(5H)-furanone (37): To a solution of g-(a-
hydroxyalkyl)butenolide 5 (22.4 mg, 55.7 mmol) in THF (3 mL;
the solvent contained 250 mg 2,6-di-tert-butyl-4-cresol per L and
was degassed prior to use) was added DEAD (17.6 mL, 19.4 mg,
111 mmol, 2.0 equiv) at ꢀ308C under argon atmosphere and
exclusion of light. After 10 min PPh3 (29.2 mg, 111 mmol,
2.0 equiv) was added, and the reaction mixture was stirred at
ꢀ308C for another 2 h. Two-thirds of the solvent was removed
under reduced pressure at ꢀ308C. A small portion of chroma-
tography eluent (1 mL) was added, and this mixture was
subjected to flash chromatography (cyclohexane:EtOAc 10:1
with 0.7 vol% NEt3; degassed) which rendered the product
(19.2 mg, 90%) as an intensely yellow solid. For selected
1H NMR (500.0 MHz, C6D6) data see Scheme 6.
[22] Monoketone 14 and the sodium derivative of a commercial 90:10
=
=
ꢀ
ꢀ
ꢀ
trans:cis mixture of (EtO)2P( O) CH2 CH CH CO2Et gave
all four diene stereoisomers of the ethyl ester/Weinreb amide
analogue of 18 in a combined yield of 49%.
[23] A. J. Mancuso, D. Swern, Synthesis 1981, 165 – 185.
[24] K. Ando, T. Oishi, M. Hirama, H. Ohno, T. Ibuka, J. Org. Chem.
2000, 65, 4745 – 4749, and references therein.
[25] T. Olpp, R. Brꢁckner, Synthesis 2004, 2135 – 2152.
[26] N. Mꢁller, W. Hoffmann, Synthesis 1975, 781 – 781.
[27] B. S. Crombie, C. Smith, C. Z. Varnavas, T. W. Wallace, J. Chem.
Soc. Perkin Trans. 1 2001, 206 – 215.
[28] a) T. Oritani, K. Yamashita, Phytochemistry 1983, 22, 1909 –
1912; b) A. Abad, C. Agullꢅ, M. Arnꢅ, A. C. Cuꢆat, R.
Zaragozꢇ, Synlett 1993, 895 – 896; c) R. Okazaki, H. Kiyota, T.
Oritani, Biosci. Biotechnol. Biochem. 2000, 64, 1444 – 1447.
[39] Following the suggestion of a referee, we also conducted the
Stille coupling of the (dienoic ester)-containing bromobuteno-
1556
ꢀ 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2005, 44, 1553 –1557