Full Papers
doi.org/10.1002/ejoc.202100251
(
4
(
d, J=8.2 Hz, CH), 70.72 (CH), 67.22 (CH ), 45.89 (C), 44.46 (CH ),
Elemental analysis calc forC H FNO: C 76.22, H 7.41, N 4.68, found:
19 22
C 76.13, H 7.40, N 4.66.
2
2
1.57 (CH ), 40.95 (2xCH ), 39.49 (CH ), 34.25 (CH ), 29.02(CH ). ESI
2
2
2
2
2
+
+)-MS: m/z (%)=409 (100) [M+1] . Elemental analysis calcd for
C H FN O : C 70.57, H 6.17, N 6.86, found: C 70.69, H 6.17, N 6.89.
2
4
25
2
3
2
,3,5,6,6’,7’,9’,9a’-octahydro-8’H-spiro[pyran-4,10’-[6,9]
ethanopyrido[1,2-a]indol]-8’-one (3p/3’p)
6
’,7’,9’,9a’-tetrahydro-8’H-spiro[cyclohexane-1,10’-[6,9]
General procedure was followed using: 2’,3’,5’,6’-tetrahydrospiro
ethanopyrido[1,2-a]indol]-8’-one (3n/3’n)
[indole-3,4’-pyran] 1d (38 mg, 0.2 mmol), Yb(OTf)3 (25 mg,
General procedure was followed using: spiro[cyclohexane-1,3’-
indole] 1a (37 mg, 0.2 mmol), Yb(OTf)3 (25 mg, 0.04 mmol) in
toluene (1.6 ml) and (cyclohexa-1,5-dien-1-yloxy)trimethylsilane 2c
0.04 mmol) in toluene (1.6 ml) and (cyclohexa-1,5-dien-1-yloxy)
trimethylsilane 2c (74 μl, 0.4 mmol). Purification by flash chroma-
tography (SiO2, cyclohexane/EtOAc 3:1 to 2:1) yielded the two
diastereoisomers 3p (18 mg, 32%) and 3’p 19 mg, 34%) as white
(74 μl, 0.4 mmol). Purification by flash chromatography (SiO2,
1
cyclohexane/EtOAc 9:1 to 8:2) yielded the two diastereoisomers
solids (m.p. T>150° C (Dec), 118.6–120.9° C, respectively). 3p: H-
3
1
7
4
1
1
2
1
n (24 mg, 43%) and 3’n (14 mg, 25%) as white solids (m.p. 132.3–
NMR (300 MHz, CDCl ) 7.19–7.10 (m, 2H), 6.85 (td, J=7.4, 0.8 Hz,
3
1
34.7° C; 61.8–63.3° C respectively). 3n: H-NMR (300 MHz, CD Cl )
1H), 6.69 (d, J=7.8 Hz, 1H), 4.13–3.99 (m, 3H), 3.89 (m, 1H), 3.60 (td,
J=11.9, 2.5 Hz, 1H), 3.51 (td, J=12.0, 2.4 Hz, 1H), 3.00 (dt, J=18.3,
2.6 Hz, 1H), 2.41-2.51 (m, 2H) 2.34–2.12 (m, 2H), 1.82–1.69 (m, 2H),
2
2
.18–7.07 (m, 2H), 6.82 (t, J=7.3 Hz, 1H), 6.69 (d, J=7.8 Hz, 1H),
.09 (d, J=3.3 Hz, 1H), 4.04 (s, 1H), 2.99 (d, J=18.3 Hz, 1H), 2.53 (s,
H), 2.43 (dd, J=18.3, 3.3 Hz, 1H), 2.18 (m, 1H), 1.98–1.81 (m, 3H),
13
1.66–1.54 (m, 3H), 1.31 (m, 1H). C-NMR (75 MHz, CDCl ) 212.6 (C),
3
13
.77–1.55 (m, 5H), 1.50–1.22 (m, 5H). C-NMR (75 MHz, CD Cl )
150.5 (C), 138.8 (C), 127.9 (CH), 122.3 (CH), 119.9 (CH), 112.4 (CH),
67.1 (CH), 65.9 (CH ), 64.3 (CH ), 50.9 (CH), 44.3 (CH ), 44.2 (CH), 44.0
2
2
12.9 (C), 150.7 (C), 140.7 (C), 127.2 (CH), 122.1 (CH), 119.3 (CH),
2
2
2
12.1 (CH), 67.1 (CH), 50.8 (CH), 46.2 (C), 44.3 (CH ), 44.2 (CH), 41.7
(C), 41.3 (CH ), 32.3 (CH ), 21.9 (CH ), 17.2 (CH ). ESI(+)-MS: m/z
2 2 2 2
+
2
(
(
CH ), 32.0 (CH ), 25.5 (CH ), 24.3 (CH ), 22.4 (CH ), 21.8 (CH ), 17.5
CH ). ESI(+)-MS: m/z (%)=282 (100) [M+1] . Elemental analysis
(%)=284 (100) [M+1] . Elemental analysis calcd for C H NO : C
2
2
2
2
2
2
18 21
2
+
1
76.30, H 7.47, N 4.94, found: C 76.48, H 7.45, N 4.92. 3’p: H-NMR
2
calcd for C H NO: C 81.10, H 8.24, N 4.98, found: C 80.93, H 8.23, N
(300 MHz, CDCl ) 7.14 (t, J=7.6 Hz, 1H), 7.08 (d, J=7.4 Hz, 1H), 6.82
(t, J=7.4 Hz, 1H), 6.69 (d, J=7.9 Hz, 1H), 4.17–4.02 (m, 3H), 3.96 (dt,
J=12.0, 3.6 Hz, 1H), 3.64 (td, J=11.8, 2.4 Hz, 1H), 3.54 (td, J=11.7,
19
23
3
1
4
.98. 3’n: H-NMR (300 MHz, CDCl ) 7.08 (td, J=7.8, 1.2 Hz, 1H), 7.01
d, J=6.8 Hz, 1H), 6.76 (td, J=7.4, 0.9 Hz, 1H), 6.64 (d, J=7.9 Hz,
3
(
1
1
H), 4.08 (m, 1H), 3.96 (s, 1H), 2.70 - 2.75 (m, 2H), 2.31 (m, 1H), 2.17–
.80 (m, 6), 1.71–1.58 (m, 4H), 1.46–1.23 (m, 4H). C-NMR (75 MHz,
2.8 Hz, 1H), 2.69–2.57 (m, 2H), 2.34 (m, 1H), 2.26–1.89 (m, 6H), 1.79
13
13
(m, 1H), 1.63 (m, 1H). C-NMR (75 MHz, CDCl ) 213.3 (C), 149.0 (C),
3
CDCl ) 213.54 (C), 148.98 (C), 139.86 (C), 127.78 (CH), 123.19 (CH),
138.1 (C), 128.4 (CH), 123.2 (CH), 120.6 (CH), 112.6 (CH), 72.7 (CH),
66.0 (CH ), 64.5 (CH ), 49.8 (CH), 44.7 (C), 44.4 (CH), 41.6 (CH ), 40.9
3
120.15 (CH), 112.41 (CH), 73.03 (CH), 49.90 (CH), 47.04 (C), 44.31
2
2
2
(
2
[
CH), 41.63 (CH ), 41.30 (CH ), 31.42 (CH ), 25.42 (CH ), 24.38 (CH ),
(CH ), 31.5 (CH ), 24.3 (CH ), 23.0 (CH ). ESI(+)-MS: m/z (%)=284
2 2 2 2
+
2
2
2
2
2
3.90 (CH ), 23.31 (CH ), 22.61 (CH ). ESI(+)-MS: m/z (%)=282 (70)
(100) [M+1] . Elemental analysis calcd for C H NO : C 76.30, H
18 21 2
2
2
2
+
M+1] . Elemental analysis calcd for C H NO: C 81.10, H 8.24, N
7.47, N 4.94, found: C 76.07, H 7.46, N 4.95.
19
23
4.98, found: 80.85, H 8.26, N 4.96.
2
’-methyl-2,3,5,6,6’,7’,9’,9a’-octahydro-8’H-spiro
2
’-fluoro-6’,7’,9’,9a’-tetrahydro-8’H-spiro
[pyran-4,10’-[6,9]ethanopyrido[1,2-a]indol]-8’-one (3q/3’q)
[
(
cyclohexane-1,10’-[6,9]ethanopyrido[1,2-a]indol]-8’-one
3o/3’o)
General procedure was followed using: 5-methyl-2’,3’,5’,6’-tetrahy-
drospiro[indole-3,4’-pyran] 1e (40 mg, 0.2 mmol), Yb(OTf) (25 mg,
3
General procedure was followed using: 5’-fluorospiro[cyclohexane-
,3’-indole] 1c (41 mg, 0.2 mmol), Yb(OTf) (25 mg, 0.04 mmol) in
0.04 mmol) in toluene (1.6 ml) and (cyclohexa-1,5-dien-1-yloxy)
trimethylsilane 2c (74 μl, 0.4 mmol). Purification by flash chroma-
tography (SiO2, cyclohexane/EtOAc 3:1 to 2:1) yielded the two
diastereoisomers 3q (14 mg, 24%) and 3’q (10 mg, 16%) as white
1
3
toluene (1.6 ml) and (cyclohexa-1,5-dien-1-yloxy)trimethylsilane 2c
74 μl, 0.4 mmol). Purification by flash chromatography (SiO2,
cyclohexane/EtOAc 8:2) yielded the two diastereisomers 3o
(
1
solid (m.p. T>157.9° C (Dec); T>107° C (Dec), respectively). H-
(
(
6
2
1
1
2
13 mg, 22%) and 3’o (21 mg, 36%) as white solids (m.p. T>68° C
NMR (300 MHz, CDCl ) 6.99–6.91 (m, 2H), 6.59 (d, J=7.9 Hz, 1H),
3
1
Dec), 78.3–81.6° C, respectively). 3o: H-NMR (300 MHz, CDCl )
4.10 (s, 1H), 4.08–4.00 (m, 2H), 3.89 (m, 1H), 3.65–3.45 (m, 2H), 2.98
3
.86–6.75 (m, 2H), 6.55 (dd, J=8.3, 4.3 Hz, 1H), 4.06–3.93 (m, 2H),
.97 (dt, J=18.3, 2.7 Hz, 1H), 2.51 (t, J=3.0 Hz, 1H), 2.42 (dd, J=
8.4, 3.4 Hz, 1H), 2.14 (m, 1H), 1.85–1.76 (m, 3H), 1.73–1.55 (m, 5H),
(m, 1H), 2.44 (dd, J=18.6, 3.2 Hz, 2H), 2.31 (s, 3H), 2.30–2.11 (m, 2H),
13
1.81–1.68 (m, 2H), 1.64–1.53 (m, 3H), 1.30 (m, 1H). C-NMR (75 MHz,
CDCl ) 212.7 (C), 148.1 (C), 138.9 (C), 129.3 (C), 128.4 (CH), 122.9
(CH), 112.3 (CH), 67.1 (CH), 65.9 (CH ), 64.4 (CH ), 51.0 (CH), 44.3
), 32.3 (CH ), 21.7 (CH ), 20.9
). ESI(+)-MS: m/z (%)=298 (100) [M+1] . Elemental
3
13
.41–1.21 (m, 5H). C-NMR (75 MHz, CDCl ) 213.0 (C), 157.5 (d, J=
2
2
3
36.5 Hz, C), 146.3 (C), 142.2 (d, J=6.9 Hz, C), 113.6 (d, J=23.4 Hz,
(CH
(CH
2
), 44.2 (CH), 44.0 (C), 41.4 (CH
), 17.2 (CH
2
2
2
+
CH), 112.4 (d, J=8.4 Hz, CH), 109.6 (d, J=23.9 Hz, CH), 67.4 (CH),
1.1 (CH), 46.4 (C), 44.3 (CH ), 43.9 (CH), 41.5 (CH ), 31.9 (CH ), 25.3
3
2
5
analysis calcd for C19
H 7.83, N 4.73. 3’q: H-NMR (300 MHz, CDCl
H
23NO
2
: C 76.74, H 7.80, N 4.71, found: C 76.51,
) 6.92 (dd, J=8.0,
2
2
2
1
(
(
CH ), 24.1 (CH ), 22.2 (CH ), 21.6 (CH ), 17.3 (CH ). ESI(+)-MS: m/z
%)=300 (100) [M+1] . Elemental analysis calc forC H FNO: C
3
2
2
2
2
2
+
1.0 Hz, 1H), 6.85 (s, 1H), 6.56 (d, J=8.0 Hz, 1H), 4.08–3.99 (m, 3H),
3.92 (dt, J=11.9, 3.6 Hz, 1H), 3.61 (td, J=11.8, 2.5 Hz, 1H), 3.51 (td,
J=11.6, 2.9 Hz, 1H), 2.67–2.55 (m, 2H), 2.31 (m, 1H), 2.25 (s, 3H),
19
22
1
76.22, H 7.41, N 4.68, found: C 76.44, H 7.43, N 4.67. 3’o: H-NMR
(
300 MHz, CDCl ) 6.80 (dd, J=8.7, 2.6 Hz, 1H), 6.73 (m, 1H), 6.54 (dd,
3
13
J=8.5, 4.4 Hz, 1H), 4,05–3.96 (m, 2H), 2.67–2.53 (m, 2H), 2.29 (m,
2.16–1.84 (m, 6H), 1.76 (m, 1H), 1.60 (m, 1H). C-NMR (75 MHz,
CDCl ) 213.1 (C), 146.6 (C), 138.2 (C), 129.9 (C), 128.9 (CH), 123.8
(CH), 112.5 (CH), 72.9 (CH), 65.9 (CH ), 64.5 (CH ), 50.0 (CH), 44.7 (C),
44.4 (CH), 41.5 (CH ), 41.0 (CH ), 31.4 (CH ), 24.3 (CH ), 23.0 (CH ),
20.9 (CH ). ESI(+)-MS: m/z (%)=298 (100) [M+1] . Elemental
13
1
H), 2.16–1.96 (m, 3H), 1.72–1.57 (m, 4H), 1.45–1.26 (m, 4H). C-NMR
3
(
(
1
4
2
75 MHz, CDCl ) 213.3 (C), 157.8 (d, J=237.2 Hz, C), 144.9 (C), 141.5
d, J=7.2 Hz, C), 114.2 (d, J=23.6 Hz, CH), 112.7 (d, J=8.3 Hz, CH),
10.5 (d, J=23.7 Hz, CH), 73.3 (CH), 50.2 (CH), 47.2 (C), 44.1 (CH),
2
2
3
2
2
2
2
2
+
3
1.4 (CH ), 41.1 (CH ), 31.2 (CH ), 25.3 (CH ), 24.3 (CH ), 23.7 (CH ),
analysis calcd for C19
H 7.79, N 4.70.
H
23NO
: C 76.74, H 7.80, N 4.71, found: C 76.86,
2
2
2
2
2
2
2
+
3.0 (CH ), 22.5 (CH ). ESI(+)-MS: m/z (%)=300 (100) [M+1] .
2
2
Eur. J. Org. Chem. 2021, 2440–2447
2446
© 2021 Wiley-VCH GmbH