12476 J. Am. Chem. Soc., Vol. 123, No. 50, 2001
Trost et al.
3-yn-1-ol (0.003 mL, 0.025 mmol). The tube was capped and then
heated to 60 °C with stirring for 6 h. The reaction was then cooled to
room temperature and chromatographed directly.
(1 mL) at 80 °C for 2 h. The toluene was evaporated under reduced
pressure, and the crude material purified by chromatograpy on silica
gel to yield 68 mg of 77 (77%) as a colorless oil. The Diels-Alder
adduct 77 (30.0 mg, 0.081 mmol) was redissolved in methanol (4 mL).
This solution was cooled to 0 °C and acetyl chloride (15.8 mg, 0.014
mL, 0.202 mmol) was added to generate anhydrous HCl. The reaction
was allowed to warm to room temperature and stirred for 16 h. The
solvent was then evaporated by rotary evaporation and the crude
material chromatographed (1:3 petroleum ether:ether) on silica gel to
yield 18.0 mg (68%) of 78 as a colorless oil.
A typical example is given below.
DMF (1 mL) was added to CpRu(COD)Cl (7.7 mg, 0.025 mmol)
and CeCl3‚7H2O (14.0 mg, 0.0375 mmol) in a pressure tube, followed
by 1-acetoxy-4,5-hexadiene (35 mg, 0.25 mmol), methyl vinyl ketone
(26.5 mg, 0.375 mmol), and hex-3-yn-1-ol (0.003 mL, 0.025 mmol).
The tube was capped and then heated to 60 °C with stirring for 6 h.
The reaction was then cooled to room temperature and chromatographed
(1:1 petroleum ether:ether) directly to give 42.9 mg (81%) of 1,3-diene
32.
Compound 77. Colorless oil. Rf: 0.11 (1:3 petroleum ether:ethyl
ether). IR (neat): 2954, 2852, 1733, 1707, 1598, 1500, 1439, 1386,
1244, 1184, 1039, 952 cm-1. 1H NMR (500 MHz, CDCl3): δ 7.47 (t,
J ) 7.7, 2H), 7.39 (t, J ) 7.4, 1H), 7.20 (d, J ) 7.3, 2H), 5.49 (1H),
4.40-4.35 (m, 1H), 4.26-4.21 (m, 1H), 3.49-3.28 (m, 2H), 2.70 (d,
J ) 14.9, 1H), 2.54-2.50 (m, 2H), 2.47-2.46 (m, 1H), 2.41-2.38
(m, 1H), 2.35-2.26 (m, 3H), 2.16-2.10 (m, 1H), 2.09 (s, 3H), 2.0 (s,
3H). 13C NMR (125 MHz, CDCl3): δ 207.4, 178.6, 176.7, 171.1, 139.8,
131.7, 129.0, 128.6, 126.4, 125.7, 62.6, 42.5, 40.9, 40.6, 33.3, 30.3,
30.2, 29.8, 28.2, 21.0. Anal. Calcd for C22H25NO5: C, 68.92; H, 6.52;
N, 3.65. Found: C, 68.75; H, 6.28; N, 3.51.
1-Acetoxy-E-3-nonen-5-methylene-8-one (32). Light yellow oil.
Rf: 0.39 (1:1 petroleum ether:ether). IR (neat): 2958, 1739, 1716, 1650,
1
1609, 1434, 1386, 1365, 1240, 1162, 1038, 971 cm-1. H NMR (300
MHz, CDCl3): δ 6.12 (d, J ) 15.9, 1H), 5.64 (dt, J1 ) 15.9, J2 ) 7.1,
1H), 4.93 (s, 1H), 4.87 (s, 1H), 4.10 (t, J ) 6.7, 2H), 2.62 (t, J ) 7.3,
2H), 2.48-2.38 (m, 4H), 2.15 (s, 3H), 2.04 (s, 3H). 13C NMR (75 MHz,
CDCl3): δ 208.2, 171.1, 144.4, 134.1, 125.1, 114.6, 63.6, 42.1, 32.1,
30.0, 25.7, 20.9. Anal. Calcd for C12H18O3: C, 68.55; H, 8.63. Found:
C, 68.56; H, 8.55.
General Procedure B. The allene (0.25 mmol) and methyl vinyl
ketone (0.375 mmol, 0.032 mL, 1.5 equiv), dissolved in DMF (1 mL),
were added to [CpRu(CH3CN)3]PF6 (10.9 mg, 0.025 mmol, 0.1 equiv)
and CeCl3‚7H2O (14.0 mg, 0.0375 mmol, 0.15 equiv) in a pressure
tube. The tube is capped and then heated to 60 °C for 4 h. It is then
cooled to room temperature, and after adding 50 mL of ether the
reaction mixture is washed three times with saturated sodium bicarbon-
ate solution and dried over MgSO4. Removal of the solvent by rotary
evaporation gave a crude oil which was chromatographed on silica gel.
A typical example is given below.
The allene 10 (49 mg, 0.25 mmol) and methyl vinyl ketone (26.5
mg, 0.375 mmol, 0.032 mL, 1.5 equive), dissolved in DMF (1 mL),
were added to [CpRu(CH3CN)3]PF6 (10.9 mg, 0.025 mmol, 0.1 equiv)
and CeCl3‚7H2O (14.0 mg, 0.0375 mmol, 0.15 equiv) in a pressure
tube. The tube is capped and then heated to 60 °C for 4 h. It is then
cooled to room temperature, and after adding 50 mL of ether the
reaction mixture is washed three times with saturated sodium bicarbon-
ate solution and dried over MgSO4. Removal of the solvent by rotary
evaporation gave a crude oil which was chromatographed (ether) on
silica gel to give 54 mg (81%) of 1,3-diene 55.
Compound 78. Colorless oil. Rf: 0.13 (1:2 petroleum ether:ethyl
acetate). IR (neat): 3342, 2922, 2854, 1711, 1599, 1536, 1497, 1441,
1
1409, 1359, 1320, 1161 cm-1. H NMR (500 MHz, CDCl3): δ 8.75
(brs, 1H), 7.57 (d, J ) 7.6, 2H), 7.35 (t, J ) 8.1, 1H), 7.13 (t, J ) 7.4,
2H), 5.36 (s, 1H), 4.37-4.32 (m, 1H), 4.30-4.25 (m, 1H), 3.73 (d, J
) 7.6, 1H), 3.40 (dd, J ) 6.6, 2.9, 1H), 3.03 (m, 1H), 2.87-2.83 (m,
1H), 2.61 (t, J ) 7.2, 2H), 2.39-2.31 (m, 2H), 2.28-2.33 (m, 1H),
2.18 (s, 3H), 1.80-1.74 (m, 2H). 13C NMR (125 MHz, CDCl3): δ
210.6, 184.7, 137.9, 137.5, 128.9, 124.3, 123.9, 120.3, 119.9, 66.5,
45.2, 41.5, 40.7, 33.6, 30.9, 30.1, 28.7, 28.0. HRMS: calcd for C20H34-
NO4 341.1627, found 341.1620.
Acknowledgment. We thank the National Science Founda-
tion and the National Institutes of Health, General Medical
Sciences, for their generous support of our programs. Mass
spectra were provided by the Mass Spectrometry Regional
Center of the University of CaliforniasSan Francisco, supported
by the NIH Division of Research Resources. A.B.P. thanks
Abbott Laboratories, Glaxo-Wellcome, the ACS Division of
Organic Chemistry (sponsored by Bristol-Myers Squibb) and
Eli Lilly for fellowship support. M.S. was supported by the
Deutscher Akademischer Austauschdienst (DAAD).
Ethyl 3-n-Pentyl-4-methylene-E-2-octen-7-one (55). Intense yellow
oil. Rf: 0.32 (ether). IR (neat): 3090, 2930, 2860, 1717, 1640, 1494,
1
1461, 1394, 1361, 1265, 1160, 1128, 1059, 899 cm-1. H NMR (300
MHz, CDCl3): δ 5.94 (s, 1H), 5.15 (s, 1H), 5.00 (s, 1H), 2.98 (s, 3H),
2.96 (s, 3H), 2.55 (t, J ) 6.9, 2H), 2.48 (t, J ) 6.9, 2H), 2.40 (t, J )
7.2, 2H), 2.12 (s, 3H), 1.40-1.18 (m, 6H), 0.86 (t, J ) 6.6, 3H). 13C
NMR (75 MHz, CDCl3): δ 207.9, 168.5, 149.1, 146.5, 119.4, 114.3,
42.3, 37.8, 34.6, 31.8, 30.0, 29.5, 28.5, 27.7, 22.4, 14.0.
Anal. Calcd for C16H27O2N: C, 72.41; H, 10.25; N, 5.28. Found:
C, 72.60; H, 10.37; N, 4.95.
Synthesis of Bicyclic Lactone 78. The diene 32 (50 mg, 0.24 mmol)
and N-phenylmaleimide (54.0 mg, 0.33 mmol) were heated in toluene
Supporting Information Available: Text giving experi-
mental details and tables listing characterization data (PDF).
This material is available free of charge via the Internet at
JA011428G