Rh(II)-Catalyzed Reactions of R-Diazo Carbonyls
J . Org. Chem., Vol. 61, No. 1, 1996 69
mL of wet acetone was stirred at 80 °C for 12 h. After the
solvent was removed under reduced pressure, the reaction
mixture was diluted with ether, washed with a saturated
NaHCO3 solution, and dried over anhydrous Na2SO4. The
solvent was removed under reduced pressure, and the result-
ing residue was chromatographed on silica gel to give 2.68 g
(89%) of methyl 2-(3-butenyl)-3-benzoylpropionate as a color-
4-oxo-4-phenyl-3-(2-propenyl)butyric acid as a viscous yellow
oil: IR (neat) 2981, 1702, 1603, and 1453 cm-1
;
1H NMR
(CDCl3, 300 MHz) δ 2.35 (dt, 1H, J ) 14.5 and 7.5 Hz), 2.51
(dd, 1H, J ) 12.1 and 6.0 Hz), 3.56 (dd, 1H, J ) 17.3 and 4.8
Hz), 2.76 (dd, 1H, J ) 17.3 and 9.5 Hz), 2.94-3.03 (m, 1H),
5.10-5.15 (m, 2H), 5.68-5.82 (m, 1H), 7.48 (t, 2H, J ) 7.5
Hz), 7.60 (t, 1H, J ) 7.5 Hz), 8.09 (d, 2H, J ) 7.5 Hz), and
10.58 (s, 1H); 13C NMR (CDCl3, 75 MHz) δ 34.5, 35.5, 40.4,
118.4, 128.4, 129.1, 130.1, 133.8, 172.2, 178.3, and 180.4.
To a solution containing 1.5 g (7.0 mmol) of the above acid
and 0.65 mL (8.5 mmol) of methyl chloroformate in 100 mL of
ether was added 0.98 mL (7.0 mmol) of triethylamine. The
resulting white suspension was stirred at rt for 1 h. The
precipitated triethylamine hydrochloride was removed by
filtration, and the resulting clear solution was immediately
treated with 40 mmol of diazomethane at 0 °C. The mixture
was allowed to warm to rt overnight, and the excess diazo-
methane was removed under reduced pressure. The resulting
oil was chromatographed on silica gel to give 1.2 g (75%) of
1-diazo-5-phenyl-4-(2-propenyl)-2,5-pentanedione (13) as a
1
less oil: IR (neat) 1734, 1449, 1217, and 691 cm-1; H NMR
(CDCl3, 300 MHz) δ 1.62-1.76 (m, 1H), 1.78-1.89 (m, 1H),
2.13 (q, 2H, J ) 7.4 Hz), 3.04 (dd, 1H, J ) 18.5 and 4.7 Hz),
3.07-3.15 (m, 1H), 3.47 (dd, 1H, J ) 18.5 and 10.1 Hz), 3.70
(s, 3H) 4.97-5.08 (m, 2H), 5.74-5.88 (m, 1H), 7.45 (t, 2H, J )
7.3 Hz), 7.56 (t, 1H, J ) 7.3 Hz), and 7.96 (d, 2H, J ) 7.3 Hz).
A solution containing 1.90 g (7.71 mmol) of the above ester
in 100 mL of THF was treated with 0.99 g (7.71 mmol) of
potassium trimethylsilanolate. After the solution was stirred
at 25 °C for 2 h, 0.90 mL (11.6 mmol) of methyl chloroformate
was added. The reaction mixture was stirred for 4 h at rt and
was then treated with 50 mmol of diazomethane in ether at 0
°C. The solution was allowed to warm to 25 °C over a 12 h
interval. The solvent was removed under reduced pressure,
and the resulting oil was chromatographed on silica gel to give
1.26 g (64%) of 3-(3-butenyl)-1-diazo-5-phenyl-2,5-pentanedione
bright yellow oil: IR (neat) 2105, 1739, and 1683 cm-1
;
1H
NMR (CDCl3, 300 MHz) δ 2.15-2.26 (m, 1H), 2.41-2.57 (m,
2H), 2.90-2.98 (m, 1H), 4.05-4.14 (m, 1H), 5.00-5.05 (m, 2H),
5.28 (s, 1H), 5.58-5.74 (m, 1H), and 7.42-7.57 (m, 5H); 13C
NMR (CDCl3, 75 MHz) δ 32.1, 36.3, 41.6, 55.0, 117.8, 125.7,
128.4, 128.6, 133.1, 134.3, 193.2, and 202.1.
(9) as a yellow oil: IR (neat) 2103, 1686, 1351, and 691 cm-1
;
1H NMR (CDCl3, 300 MHz) δ 1.38-1.47 (m, 1H), 1.62-1.69
(m, 1H), 1.97 (dd, 2H, J ) 14.5 and 7.3 Hz), 2.85 (dd, 1H, J )
18.0 and 9.0 Hz), 2.83-2.99 (m, 1H), 3.40 (dd, 1H, J ) 18.0
and 3.8 Hz), 4.83-4.93 (m, 2H), 5.39 (s, 1H), 5.51-5.73 (m,
1H), 7.26 (t, 2H, J ) 7.3 Hz), 7.37 (t, 1H, J ) 7.3 Hz), and
7.79 (d, 2H, J ) 7.3 Hz); 13C NMR (CDCl3, 75 MHz) δ 30.7,
37.2, 40.3, 43.9, 54.6, 114.9, 127.5, 128.1, 132.7, 136.0, 137.1,
196.8, and 197.6.
3,5-Met h a n o-8-oxa t r icyclo-7-oxo-4-p h en yl[3.2.1.01,4]-
octa n e (14) was isolated as a clear oil: IR (neat) 2960, 1725,
1
and 1127 cm-1; H NMR (CDCl3, 300 MHz) δ 1.41 (dt, 1H, J
) 13.1 and 2.5 Hz), 2.27 (d, 1H, J ) 13.1 Hz), 2.67-2.77 (m,
1H), 2.83 (dd, 1H, J ) 16.4 and 1.6 Hz), 3.00-3.10 (m, 1H),
3.46 (dd, 1H, J ) 16.4 and 6.2 Hz), 3.50-3.57 (m, 1H), 3.65-
3.73 (m, 1H), 4.73 (d, 1H, J ) 6.6 Hz), and 7.30-7.56 (m, 5H);
13C NMR (CDCl3, 75 MHz) δ 27.9, 37.0, 37.4, 39.2, 43.3, 84.5,
85.6, 124.6, 127.5, 128.4, 141.0, and 213.2; HRMS calcd for
C14H14O2 214.0994, found 214.0994.
8-P h en yl-7-oxa tr icyclo[4.3.1.03,8]d eca n -10-on e (10): mp
140-141 °C; IR (KBr) 1735, 1034, and 704 cm-1 1H NMR
;
(CDCl3, 300 MHz) δ 1.45-1.59 (m, 1H), 1.81 (ddd, 1H, J )
14.5, 7.7, and 3.3 Hz), 2.17-2.37 (m, 4H), 2.42-2.61 (m, 3H),
3.13 (dd, 1H, J ) 9.2 and 8.6 Hz), 4.31 (dd, 1H, J ) 8.2 and
1.7 Hz), and 7.23-7.45 (m, 5H); 13C NMR (CDCl3, 75 MHz) δ
21.1, 30.6, 40.4, 41.4, 42.0, 50.5, 82.6, 83.9, 124.5, 127.1, 128.2,
143.4, and 210.8. Anal. Calcd for C15H16O2: C, 78.92; H, 7.06.
Found: C, 78.95; H, 7.01.
tr a n s-4-Ben zoylbicyclo[4.1.0]h ep ta n -2-on e (15) was iso-
lated as an oil: IR (neat) 2931, 1683, 1598, and 1580 cm-1; 1H
NMR (CDCl3, 300 MHz) δ 1.06 (dd, 1H, J ) 10.7 and 5.1 Hz),
1.35 (td, 1H, J ) 9.0 and 5.1 Hz), 1.77-1.84 (m, 2H), 1.92 (dd,
1H, J ) 13.0 and 12.0 Hz), 2.29-2.36 (m, 1H), 2.37-2.44 (m,
1H), 2.50 (dd, 1H, J ) 15.0 and 13.0 Hz), 3.85-3.96 (m, 1H),
and 7.26-7.93 (m, 5H); 13C NMR (CDCl3, 75 MHz) δ 19.1, 24.7,
26.7, 38.6, 45.7, 128.3, 128.7, 128.8, 133.5, 135.2, 199.7, and
209.1; HRMS calcd for C14H14O2 214.0994, found 214.0992.
1-Hyd r oxy-5-p h en yl-4-(2-p r op en yl)-2,5-p en ta n ed ion e
(18) was isolated as a clear oil: IR (neat) 2954, 1737, and 1683
1-P h en yl-7-oxa tr icyclo[4.3.1.03,8]d eca n -9-on e (11): mp
154-155 °C; IR (KBr) 1731, 1080, and 698 cm-1 1H NMR
;
(CDCl3, 300 MHz) δ 1.72 (dd, 1H, J ) 7.5 and 3.5 Hz), 1.90
(dd, 1H, J ) 8.2 and 3.5 Hz), 1.99-2.17 (m, 2H), 2.17-2.37
(m, 2H), 2.42-2.61 (m, 2H), 2.71 (dt, 1H, J ) 8.5 and 2.0 Hz),
2.72 (dd, 1H, J ) 9.9 and 2.0 Hz), 4.41 (d, 1H, J ) 6.9 Hz),
and 7.27-7.48 (m, 5H); 13C NMR (CDCl3, 75 MHz) δ 22.6, 22.9,
34.6, 39.0, 41.5, 41.9, 82.6, 83.3, 124.1, 127.2, 128.3, 144.4, and
211.3. Anal. Calcd for C15H16O2: C, 78.92; H, 7.06. Found:
C, 78.89; H, 7.10.
1
cm-1; H NMR (CDCl3, 300 MHz) δ 2.40 (m, 1H), 2.65 (ddd,
1H, J ) 14.5, 7.5, and 7.0 Hz), 2.97 (dd, 1H, J ) 13.2 and 7.5
Hz), 3.06 (dd, 1H, J ) 17.0 and 4.8 Hz), 3.53 (dd, 1H, J ) 17.0
and 9.3 Hz), 3.61 (s, 2H), 4.74-4.83 (m, 1H), 5.04-5.09 (m,
2H), 5.78-5.92 (m, 1H), 7.47 (t, 2H, J ) 6.0 Hz), 7.56 (t, 1H,
J ) 6.0 Hz), and 7.98 (d, 2H, J ) 6.0 Hz); 13C NMR (CDCl3, 75
MHz) δ 34.9, 36.4, 41.9, 51.7, 117.9, 128.4, 128.7, 133.1, 134.2,
137.8, 188.0, and 201.9; HRMS calcd for C14H16O3 232.1100,
found 232.1104.
tr a n s-3-(2-P h en yl-2-et h yl)b icyclo[4.1.0]h ep t a n -2-on e
(12): IR (neat) 1717, 1221, and 691 cm-1 1H NMR (CDCl3,
;
300 MHz) δ 1.18 (dd, 1H, J ) 10.6 and 5.2 Hz), 1.24-1.32 (m,
1H), 1.59-1.66 (m, 1H), 1.72-1.83 (m, 2H), 1.84-1.93 (m, 2H),
2.05-2.17 (m, 1H), 2.70 (dd, 1H, J ) 17.6 and 7.1 Hz), 2.87-
2.98 (m, 1H), 3.55 (dd, 1H, J ) 17.6 and 5.2 Hz), 7.43 (t, 2H,
J ) 7.4 Hz), 7.52 (t, 1H, J ) 7.4 Hz), and 7.95 (d, 2H, J ) 7.4
Hz); 13C NMR (CDCl3, 75 MHz) δ 18.1, 21.2, 22.3, 25.8, 32.1,
38.7, 40.1, 128.0, 128.5, 133.0, 137.0, 198.6, and 210.4. Anal.
Calcd for C15H16O2: C, 78.92; H, 7.06. Found: C, 78.91; H,
7.09.
P r ep a r a tion of 1-Dia zo-5-p h en yl-4-(2-p r op en yl)-2,5-
p en ta n ed ion e (13). To a solution containing 6.7 g (42 mmol)
of 1-phenyl-4-pentenone in 200 mL of THF was added 100 mL
(50 mmol) of 0.5 M potassium bis(trimethylsilyl)amide at -78
°C. The solution was stirred for 0.5 h after which 6.9 mL (63
mmol) of ethyl 2-bromoacetate was added. The reaction
mixture was allowed to warm to rt for 2 h and cooled to 0 °C,
the reaction was quenched with 100 mL of 5% HCl, and the
solution was extracted with ether. The organic extracts were
treated with 100 mL of 10% KOH and 100 mL of methanol at
rt for 2 h. The crude reaction mixture was washed with ether
and acidified with 10% HCl. The solution was extracted with
ether, washed with brine, dried over anhydrous MgSO4, and
concentrated under reduced pressure to give 6.9 g (75%) of
4-(2,4,6-Cycloh ep t a t r ien yl)-1-p h en yl-2-(2-p r op en yl)-
1,4-bu ta n ed ion e (19) was isolated (87%) as a clear viscous
liquid when the reaction was carried out using benzene as the
solvent: IR (neat) 2979, 1717, and 1681 cm-1; 1H NMR (CDCl3,
300 MHz) δ 2.14 (ddd, 1H, J ) 14.6, 8.0, and 6.8 Hz), 2.38-
2.46 (m, 2H), 2.69 (dd, 1H, J ) 18.2 and 4.0 Hz), 3.24 (dd, 1H,
J ) 18.2 and 4.0 Hz), 4.01-4.08 (m, 1H), 4.97-5.08 (m, 4H),
5.59-5.73 (m, 1H), 6.22-6.29 (m, 2H), 6.53-6.55 (m, 2H), 7.43
(t, 2H, J ) 7.5 Hz), 7.52 (t, 1H, J ) 7.5 Hz), and 7.97 (d, 2H,
J ) 7.5 Hz); 13C NMR (CDCl3, 75 MHz) δ 36.2, 40.9, 42.6, 47.9,
106.8, 107.1, 117.7, 126.0, 126.2, 128.4, 128.6, 129.7, 129.8,
132.9, 134.4, 136.3, 202.2, and 207.8; HRMS calcd for C20H20O2
292.1464, found 292.1465.
P r ep a r a tion of 4-Ben zoyl-1-d ia zo-2-oxo-7-octen e (20).
A solution of 75.8 mL (37.9 mmol) of 0.5 M potassium
hexamethyldisilazide in toluene and 45 mL of THF was cooled
to -78 °C, and 6.0 g (34.4 mmol) of 1-phenyl-5-hexen-1-one43
(43) Reissig, H.-U.; Hippeli, C. Synthesis 1991, 56, 3087.