Observation of an Unusual C–C Insertion
phane (27.7 mmol, 6.18 g, M = 223.31) was added. The resulting
brown solution was again heated to reflux for 18 h, then all vola-
tiles were carefully evaporated under high vacuum to give an
orange solid. The residue was triturated three times with cyclohex-
ane to remove impurities and the solid was then filtered and dried
under vacuum to give the title compound as an orange powder
and the mixture was stirred while warming to room temperature
over a period of 3 h. After addition of water (1 mL) to quench the
reaction, all volatiles were evaporated under vacuum. The dark-
brown residue was directly deposited on a silica gel column and
2 2 f
purified (CH Cl /PE, 5:5; R = 0.3). The relevant fractions were
evaporated to yield the title compound as a light-brown oil that
rapidly crystallized upon standing (1.43 g, 34% for two steps). IR
(
8.98 g, 86%), which was used without further purification. Col-
umn chromatography could be used (Et O/PE, 5:5; R = 0.38), but
with drastic loss of product (43% on 1.8 g scale). IR (neat): ν˜ =
–
1 1
2
f
(neat): ν˜ = 2937, 2861, 1904, 1602, 1417 cm . H NMR (300 MHz,
CDCl ): δ = 8.88 (d, J = 5 Hz, 1 H, 6-H), 7.32 (d, J = 5 Hz, 1 H,
050, 2929, 1728, 1659, 1621, 1591 cm . H NMR (300 MHz, 7-H), 7.05 and 6.95 (AB system, J = 7.3 Hz, 2 H, 11-H, 12-H),
CDCl ): δ = 11.34 (d, J = 14 Hz, 1 H, NH), 8.36 (d, J = 14 Hz, 1 6.51–6.52 (m, 2 H, 16-H, 17-H), 5.73 and 5.60 (AB system, J =
H, 17-H), 6.60 (dd, J = 2, 8 Hz, 1 H, 7-H), 6.45–6.48 (m, 3 H, 8- 7.9 Hz, 2 H, 19-H, 20-H), 4.20–4.27 (m, 1 H, 2-H), 3.98 (dd, J =
3
–1
1
3
3
H, 12-H, 13-H), 6.34–6.38 (m, 2 H, 15-H, 16-H), 6.10 (s, 1 H, 5-
9, 13.5 Hz, 1 H, 2-HЈ), 3.20 (dd, J = 9.4, 12.9 Hz, 1 H, 13-H), 3.00–
1
3
H), 3.25–3.33 (m, 1 H, 2-H), 2.77–3.11 (m, 7 H, 2-HЈ, 9-H, 10-H,
3.11 (m, 4 H, 1-H, 14-H), 2.69–2.79 (m, 1 H, 13-HЈ) ppm.
C
3
1
-H), 1.72 (s, 3 H, 21-H), 1.68 (s, 3 H, 21-HЈ) ppm. 1 C NMR
NMR (75 MHz, CDCl ): δ = 153.2, 153.0, 147.9, 139.3, 138.1,
3
2
(75 MHz, CDCl
3
): δ = 166.0 (19-C), 163.7 (19-CЈ), 152.3 (17-C), 135.4, 134.8, 134.4, 132.9, 131.8, 128.0, 127.8, 122.6, 118 (q, JC–F
1
1
42.6, 139.3, 138.9, 136.9, 136.0, 133.8, 133.4, 131.5, 130.9, 127.7,
21.9, 105.2, 87.1 (20-C), 35.1, 34.9, 33.6, 32.0, 27.2 (21-C), 27.0
= 318 Hz), 112.0, 36.6, 34.6, 34.4, 31.9 ppm. HRMS: calcd. for
NO S 408.0881; found 408.0911.
C
20
H
17
F
3
3
(
3
4
21-CЈ) ppm. HRMS: calcd. for C23H24NO 378.1705; found
78.1697.
PPY-Paracyclophane 14: In a sealed tube, triflate 13 (51.3 mg) was
dissolved in neat pyrrolidine (2 mL) and the mixture was heated to
150 °C for 10 d. The volatiles were evaporated under vacuum and
the residue was purified by column chromatography over silica gel
Quinolones 7 and 8: Into a 100 mL round-bottomed flask purged
with argon was introduced diphenyl ether (60 mL) and enamine
6
(3.8 g, 10 mmol, M = 377.43). After dissolution, the flask was
(MeOH/CH
(49.3 mg, 86%). H NMR (300 MHz, CDCl
2
Cl
2
, 5:95; R
f
= 0.2) to give the title compound
): δ = 8.59 (d, J =
1
immerged in a metallic bath heated to 260 °C. Ebullition occurred
after a few minutes and gas evolution was observed. The mixture
was maintained at this temperature for 15 min. The flask was then
taken out of the bath and the hot solution was poured with caution
into pre-cooled pentane (1 L) at 0 °C to induce precipitation of the
product. TLC analysis indicated the presence of two compounds 7
and 8 in roughly equal amounts. These compounds could be sepa-
rated by column chromatography with CH
=
used without purification in the next step.
3
5.3 Hz, 1 H, 6-H), 6.82 (d, J = 7.1 Hz, 1 H, 7-H), 6.70–6.66 (m, 2
H, 16-H, 17-H), 6.58 and 6.53 (2ϫdd AB system, J = 7.9, 1.5 Hz,
2 H, 11-H, 12-H), 5.95 and 5.57 (2ϫdd AB system, J = 7.8 Hz, 2
H, 19-H, 20-H), 4.18–4.10 (m, 1 H, 21-H), 3.76–3.67 (m, 2 H),
3.35–3.32 (m, 1 H), 3.19–3.05 (m, 3 H), 2.91–2.77 (m, 3 H), 2.7–
1
3
2.65 (m, 1 H), 2.17–1.85 (m, 3 H) ppm. C NMR (75 MHz,
CDCl ): δ = 154.5, 150.6, 146.8, 139.5, 138.2, 137.3, 137.2, 133.9,
131.7, 131.6, 131.2, 127.4, 127.1, 122.6, 104.4, 54.1, 49.1, 35.3, 35.0,
34.5, 32.6 ppm. HRMS: calcd. for C23 328.1939; found
28.1954.
2
Cl
2
/MeOH, 95:5; R
f
(8)
3
0.43 and R (7) = 0.22. For preparative purposes, the mixture was
f
24 2
H N
3
1
Compound 7: H NMR (300 MHz, CDCl
3
): δ = 10.8 (br. s, 1 H,
NH), 7.66 (t, J = 6.6 Hz, 1 H, 6-H), 6.74 (d, J = 7.3 Hz, 1 H, 12- DMAP-Paracyclophanes 16A and 16B: In a sealed tube, triflate 13
H), 6.50–6.54 (m, 2 H, 11-H, 17-H), 6.37 (dd, J = 1.7, 7.9 Hz, 1
H, 16-H), 6.16 (dd, J = 1.3, 7.7 Hz, 1 H, 2-H), 5.93–5.99 (m, 2 H,
(51 mg, 0.173 mmol) was dissolved in anhydrous toluene (10 mL)
and (S,S)-3,4-bis(tert-butyldimethylsilyloxy)pyrrolidine (15)
3
2
-H, 7-H), 4.55–4.63 (m, 1 H, 13-H), 3.59–3.64 (m, 1 H, 2-H), (287 mg, 0.867 mmol, 5 equiv.) was added. After degassing with ar-
.85–3.11 (m, 4 H), 2.68–2.82 (m, 2 H) ppm. 13C NMR (75 MHz,
): δ = 178.8 (8-C), 141.4, 140.8, 138.9, 137.6, 136.9, 135.7,
33.0, 132.2, 129.6, 129.0, 128.1, 127.8, 126.0, 110.7 (7-C), 35.0,
gon, the mixture was heated to reflux (150 °C) for 20 d by which
time, all starting material was consumed. Volatiles were removed
and the brown residue was deposited on a silica-gel column and
purified (gradient from EtOAc/PE, 3:7 to pure EtOAc). Evapora-
CDCl
3
1
3
2
3.6, 32.7, 30.9 ppm. HRMS: calcd. for C19
76.1405.
H18NO 276.1388; found
f
tion of the first fractions gave 16A (51 mg, 49.9%; R = 0.35); fol-
lowing fractions gave 16B (33 mg, 32%; R
f
= 0.27) as a brown oil.
Compound 8: IR (neat): ν˜ = 3200, 3049, 2924, 1726, 1606, 1545,
–1
1
Compound 16A: [α] 52 80 9 = +161 (c = 0.0561, CH
20
1
1
1
500 cm . H NMR (300 MHz, CD
H, 9-H), 7.62 (d, J = 8.7 Hz, 1 H, 6-H), 7.15 (dd, J = 1.3, 8.7 Hz,
3
OD): δ = 7.67 (d, J = 0.8 Hz,
2
Cl
2
), [α]365 = –27800
1
(c = 0.0561, CH
2
Cl
2
). H NMR (300 MHz, CDCl
3
): δ = 8.61 (d, J
H, 7-H), 6.68 (d, J = 1.3 Hz, 1 H, 12-H), 6.44 and 6.33 (2ϫdd = 7.9 Hz, 1 H, 6-H), 6.83 (d, J = 10.8 Hz, 1 H, 11-H), 6.71–6.67
AB system, J = 2.1, 7.9 Hz, 2 H, 19-H, 20-H), 6.19 and 6.06 (2ϫdd
AB system, J = 1.9, 7.7 Hz, 2 H, 16-H, 17-H), 3.3–3.2 (m, 1 H),
(m, 2 H, 11-H, 7-H), 6.56 and 6.51 (2ϫdd AB system, J = 2.3,
11.8 Hz, 2 H, 16-H, 17-H), 5.92 and 5.52 (2ϫdd AB system, J =
2
.94–2.85 (m, 4 H), 2.65–2.64 (m, 1 H), 2.44–2.49 (m, 2 H) ppm. 2, 11.8 Hz, 2 H, 19-H, 20-H), 4.2–3.9 (m, 4 H), 3.71–3.59 (m, 3 H),
13
C NMR (75 MHz, CD
3
OD): δ = 181.8 (8-C), 145.9, 144.3, 141.1, 3.36–3.31 (m, 1 H), 3.16–2.67 (m, 6 H), 0.93 (s, 9 H, SitBu), 0.87
1
3
1
1
2
38.7, 136.7, 131.2, 130.9, 129.6, 129.4, 128.3, 128.2, 126.0, 125.1,
17.4, 36.6, 36.1, 35.4, 25.5 ppm. HRMS: calcd. for C19
76.1388; found 276.1418.
(s, 9H SitBu), 0.08 (br. s, 12 H, SiCH
CDCl ): δ = 161.7, 154.4, 147.1, 139.5, 138.3, 137.8, 137.2, 133.8,
131.8, 131.5, 127.4, 127.2, 122.4, 105.2, 60.0, 54.9, 52.0, 50.2, 35.8,
5.3, 34.6, 32.5, 29.7, 25.8, 25.7, 18.1, –4.5, –4.6, –4.7, –4.8 ppm.
3
) ppm. C NMR (75 MHz,
H18NO
3
3
Triflate 13: The above mixture of products 7 and 8 was introduced
into a 100 mL round-bottomed flask purged with argon. Anhy-
drous dichloromethane (70 mL) was added and the resulting sus-
pension was cooled to 0 °C with an ice bath. To this solution was
added successively, DMAP (126 mg, 1.03 mmol, 0.1 equiv., M =
HRMS: calcd. for C35
H
53
N
2
O
2
Si
2
589.3646; found 589.3655.
Compound 16B: [α] 52 80 9 = –31 (c = 0.0326, CH
20
2
2
Cl ), [α]365 = –44170
1
(c = 0.0326, CH
2
Cl
2
). H NMR (300 MHz, CDCl
3
): δ = 8.58 (d, J
= 5.4 Hz, 1 H, 6-H), 6.82 (d, J = 7.1 Hz, 1 H, 11-H), 6.69–6.66 (m,
2 H, 12-H, 7-H), 6.58 and 6.51 (2ϫdd AB system, J = 1.5, 7.9 Hz,
2 H, 16-H, 17-H), 5.97 and 5.56 (2ϫdd AB system, J = 1.5, 7.7 Hz,
2 H, 19-H, 20-H), 4.17–4.0 (m, 4 H), 3.78–3.60 (m, 2 H), 3.24–315
122.17) and 2,6-lutidine (1.8 mL, 15.45 mmol, 1.5 equiv., M =
107.15, 0.92). Trifluoromethansulfonic anhydride (2.1 mL,
12.36 mmol, 1.2 equiv., M = 282.14, d 1.677) was added dropwise
d
Eur. J. Org. Chem. 2011, 1980–1984
© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
1983