References
For selected reviews on metathesis reaction, see:
<A NAME="RD10705ST-1A">1a</A>
Grubbs RH.
Chang S.
Tetrahedron
1998,
54:
4413
<A NAME="RD10705ST-1B">1b</A>
Fürstner A.
Angew. Chem. Int. Ed.
2000,
39:
3013
<A NAME="RD10705ST-1C">1c</A>
Deiters A.
Martin SF.
Chem. Rev.
2004,
104:
2199
<A NAME="RD10705ST-2">2</A> For a recent review, see:
Schmidt B.
Eur. J. Org. Chem.
2004,
1865
<A NAME="RD10705ST-3">3</A>
Bielawski CW.
Louie J.
Grubbs RH.
J. Am. Chem. Soc.
2000,
122:
12872
<A NAME="RD10705ST-4">4</A>
Louie J.
Bielawski CW.
Grubbs RH.
J. Am. Chem. Soc.
2001,
123:
11312
<A NAME="RD10705ST-5">5</A>
Simal F.
Demonceau A.
Noels AF.
Angew. Chem. Int. Ed.
1999,
38:
538
For selected recent references, see:
<A NAME="RD10705ST-6A">6a</A>
Schmidt B.
J. Org. Chem.
2004,
69:
7672
<A NAME="RD10705ST-6B">6b</A>
Van Otterlo WAL.
Ngidi EL.
de Koning CB.
Tetrahedron Lett.
2003,
44:
6483
<A NAME="RD10705ST-6C">6c</A>
Sutton AE.
Seigal BA.
Finnegan DF.
Snapper ML.
J. Am. Chem. Soc.
2002,
124:
13390
<A NAME="RD10705ST-7A">7a</A>
Maynard HD.
Grubbs RH.
Tetrahedron Lett.
1999,
40:
4137
<A NAME="RD10705ST-7B">7b</A>
Fürstner A.
Thiel OR.
Ackermann L.
Schanz HJ.
Nolan SP.
J. Org. Chem.
2000,
65:
2204
<A NAME="RD10705ST-7C">7c</A>
Bourgeois D.
Pancrazi A.
Ricard L.
Prunet J.
Angew. Chem. Int. Ed.
2000,
39:
726
<A NAME="RD10705ST-8">8</A> For mechanistic studies, see:
McGrath DV.
Grubbs RH.
Organometallics
1994,
13:
224
<A NAME="RD10705ST-9">9</A>
Michalak K.
Michalak M.
Wicha J.
Tetrahedron Lett.
2005,
46:
1149
<A NAME="RD10705ST-10A">10a</A>
Krompiec S.
Kuznik N.
Bieg T.
Adamus B.
Majnusz J.
Grymel M.
Pol. J. Chem.
2000,
74:
1197
<A NAME="RD10705ST-10B">10b</A>
Krompiec S.
Pigulla M.
Bieg T.
Szczepankiewicz W.
Kuznik N.
Krompiec M.
Kubicki M.
J. Mol. Catal. A: Chem.
2002,
189:
169
<A NAME="RD10705ST-11">11</A> For consecutive use of 7 and then 5, see:
van Otterlo WAL.
Pathak R.
de Koning CB.
Synlett
2003,
1859
<A NAME="RD10705ST-12">12</A> For the use of 5 together with a hydrogenation catalyst, see:
Cossy J.
Bargiggia FC.
BouzBouz S.
Tetrahedron Lett.
2002,
43:
6715
<A NAME="RD10705ST-13">13</A>
Typical Procedures.
Methyl (3a
R*
,4
R*
,8a
R*
)-8a-Methyl-1-oxo-1,2,3,3a,4,5,8,8a-octahydroazulene-4-carboxylate (10)
To a solution of 6 (3.9 mg, 0.0048 mmol, 3% mol) in benzene (10 mL), diene 8 (42 mg, 0.159 mmol) in benzene (10 mL) was added and the mixture was heated under
reflux for 72 h. Then solvent was evaporated, and the residue was purified by chromatography
on silica gel (5% EtOAc-hexanes) to give 10 (oil, 20 mg, 56%): HPLC. t
R = 6.42 min, 94% purity (RI detector, MeOH-H2O = 6:4). 1H NMR (500 MHz): δ = 6.08-5.97 (m, 1 H), 5.82-5.71 (m, 1 H), 3.67 (s, 3 H), 2.90-2.84
(m, 1 H), 2.72-2.63 (m, 1 H), 2.50-2.33 (m, 3 H), 2.25-2.06 (m, 3 H), 2.04-1.97 (m,
1 H), 1.96-1.87 (m, 1 H), 0.76 (s, 3 H). 13C NMR (50 MHz): δ = 221.0, 174.2, 131.5, 127.7, 53.5, 51.5, 49.4, 42.9, 35.5, 35.2,
30.4, 24.2, 14.9. HRMS: m/z calcd for C13H18O3: 222.1256; found: 222.1262.
S
-(
tert
-Butyl) (3a
R*
,4
R*
,8a
R*
)-7,8a-Dimethyl-1-oxo-1,2,3,3a,4,5,8,8a-octahydroazulene-4-carbothioate (16).
A flame-dried flask equipped with a condenser was charged with 5 (8.8 mg, 0.010 mmol, 5 mol%), 7 (9.9 mg, 0.010 mmol, 5 mol%) and benzene (10 mL). The mixture was briefly stirred
to dissolve the catalysts and then ester 12 (69.9 mg, 0.208 mmol) in benzene (10 mL) was added. The solution was heated under
reflux for 6 h. The solvent was evaporated and the residue was purified by chromatography
on silica gel (5% EtOAc-hexanes) to give 16 (61.1 mg, 100%). 1H NMR (200 MHz): δ = 5.69 (br t, J = 6.0 Hz, 1 H), 2.95-2.85 (m, 1 H), 2.65-1.90 (m, 9 H), 1.78 (s, 3 H), 1.44 (s, 9
H), 0.86 (s, 3 H). 13C NMR (50 MHz): δ = 222.8, 201.5, 136.9, 123.4, 53.2, 52.8, 49.0, 48.0, 40.2, 35.4,
30.0, 29.7, 27.4, 24.0, 15.7. HRMS: m/z calcd for C17H26O2S: 294.1654; found: 294.1651.
<A NAME="RD10705ST-14">14</A> Confer:
Bourgeois D.
Pancrazi A.
Nolan SP.
Prunet J.
J. Organomet. Chem.
2002,
643:
247
<A NAME="RD10705ST-15">15</A>
The respective β,γ-unsaturated thioester was isolated in ca. 5% yield.
Typical Procedure for
S
-(
tert
-Butyl) (2
R*
)-2-[(1
R*
,2
R*
)-2-Methyl-2-(2-methylprop-2-enyl)-3-oxocyclo-pentyl]hex-4-enethioate (20).
To a solution of 7 (5.1 mg, 0.054 mmol, 1% mol) in benzene (4 mL), 12 (180.6 mg, 0.54 mmol) in benzene (4 mL) was added and the mixture was heated under
reflux for 10 min (GC analysis indicated consumption of the substrate). The solvent
was evaporated and the residue was purified by chromatography on silica gel (5% EtOAc-hexanes)
to give 20 (157.1 mg, 87%). R
f
= 0.64 (10% EtOAc-hexanes). GC: 15.5 and 15.9 (E:Z = 2.6:1, 150-250 °C, 150 °C, 1 min, 10 °C/min). 1H NMR (200 MHz): δ = 5.64-5.26 (m, 2 H), 4.85 (br s, 1 H), 4.68 (br s, 1 H), 2.76-1.96
(m, 10 H), 1.63 (d, J = 5.2 Hz, 3 H), 1.58 (s, 3 H), 1.45 (s, 9 H), 1.03, 1.02 (s, 3 H). 13C NMR (50 MHz): δ = 222.6, 202.4, 141.5, 127.8, 126.9, 126.2, 126.0, 115.2, 55.1,
54.7, 51.6, 48.5, 43.7, 42.5, 37.5, 34.8, 29.7, 28.9, 24.6, 23.4, 23.3, 20.2, 17.8.
HRMS: m/z calcd for C32H48O6Na: 336.2123; found: 336.2126.
<A NAME="RD10705ST-16A">16a</A>
Mukaiyama T.
Tamura M.
Kobayashi S.
Chem. Lett.
1987,
743
<A NAME="RD10705ST-16B">16b</A>
Narasaka K.
Soai K.
Mukaiyama T.
Chem. Lett.
1974,
1223
<A NAME="RD10705ST-17A">17a</A>
Tsuji J.
Minami I.
Shimizu I.
Chem. Lett.
1983,
1325
<A NAME="RD10705ST-17B">17b</A>
Typical Procedure for S
-(
tert
-Butyl) (2
R*
)-2-[(1
R*
,2
R*
)-2-Allyl-2-methyl-3-oxocyclopentyl]hex-5-enethioate (15).
To a solution of 1-(tert-butylthio)-1-trimethylsilyloxyhexa-1,5-diene (1.551 g, 6 mmol, 1.2 equiv) in CH2Cl2 (45 mL), TMSOTf (45 µL, 0.3 mmol, 5 mol%), 2-methylcyclopent-2-en-1-one (0.5 mL,
5 mmol) were consecutively added at
-78 °C. The mixture was stirred for 3 h and then the reaction was quenched with 2-pyridinemethanol
(36 µL, 0.37 mmol, 7.5 mol%). After 15 min, hexane (90 mL) was added, the bright yellow
solution was filtered through silica gel (10 g, deactivated with 2% Et3N in hexane), and the solvent was evaporated to give tert-butyl (2R*)-2-{(1R*)-2-methyl-3-[1,1,1-(trimethylsilyl)oxy]-2-cyclopentenyl}-5-hexene-thioate (silyl
enol ether, oil, 1.806 g, 98%). To a solution of Pd2 (dba)3 (137 mg, 0.15 mmol, 3 mol%) and dppe (356 mg, 0.92 mmol, 18 mol%) in THF (24 mL),
the crude silyl enol ether in THF (12 mL) and allyl methyl carbonate (1.138 g, 9.8
mmol) were added. The mixture was heated under refluxed for 6 h, cooled and the solvent
was evaporated. The residue was purified by chromatography on silica gel (3% EtOAc-hexanes)
to give 15 (yellow oil, 1.58 g, 68%):
1H NMR (200 MHz): δ = 5.90-5.50 (m, 2 H), 5.10-4.92 (m, 4 H), 2.70-2.25 (m, 4 H), 2.20-1.85
(m, 5 H), 1.80-1.55 (m, 3 H), 1.49 (s, 9 H), 1.01 (s, 3 H). 13C NMR (50 MHz):
δ = 221.9, 202.9, 137.8, 133.8, 118.7, 115.3, 54.0, 52.3, 48.7, 43.1, 39.8, 37.5,
30.8, 29.6, 23.4, 18.7. HRMS: m/z calcd for C19H30O2S: 322.1967; found: 322.1970.