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4.19.1. 3-(Furan-2-yl)-3,3a,4,5,6,7-hexahydro-2-methyl-2H-
indazole (11b)
128.9 (CH), 128.5 (CH), 126.6 (CH), 76.0 (CH), 52.1 (CH), 41.3 (CH3),
28.8 (CH2), 28.3 (CH2), 25.9 (CH2), 24.3 (CH2). HRMS: (FAB) calcd for
C14H18N2 [MþH]þ 215.1548, found 215.1547.
IR (neat) 2933, 2858, 2780, 1614, 1447, 1149, 1009, 743 cmꢁ1
;
1H NMR (CDCl3)
d 7.38–7.35 (m, 1H), 6.35–6.31 (m, 1H), 6.26 (d,
J¼3.1 Hz, 1H), 3.46 (d, J¼12.7 Hz, 1H), 3.09–2.95 (m, 1H), 2.74 (s,
4.22. Synthesis of compounds (8b) and (9b)
3H), 2.65–2.54 (m, 1H), 2.19–2.03 (m, 2H), 2.00–1.91 (m, 1H),
1.87–1.78 (m, 1H), 1.53–1.18 (m, 4H); 13C NMR (CDCl3)
d
157.1
These compounds were prepared from compound 2d (0.1 g,
0.52 mmol) and methylhydrazine (0.22 mL, 4.17 mmol) using the
same procedure given for compound 11a. The crude product was
purified by column chromatography on silica (heptane/EtOAc) to
yield product 8b (58.4 mg, 51%) as a brown oil and product 9b
(26 mg, 23%) as a dark yellow oil.
(C), 152.4 (C), 142.5 (CH), 110.3 (CH), 107.6 (CH), 72.8 (CH), 51.5
(CH), 42.6 (CH3), 31.6 (CH2), 27.6 (CH2), 25.8 (CH2), 24.5 (CH2).
HRMS: (FAB) calcd for C12H16N2O [MþH]þ 205.1341, found
205.1339.
4.19.2. 3-(Furan-2-yl)-4,5,6,7-tetrahydro-1-methyl-1H-
indazole (12b)
4.22.1. 3a,4,5,6,7,7a-Hexahydro-1-methyl-3-(thiophen-2-yl)-1H-
IR (neat) 3116, 2932, 2853, 1440, 1297, 1160, 1009, 729 cmꢁ1; 1H
indazole (8b)
NMR (CDCl3)
d
7.43 (d, J¼1.7 Hz,1H), 6.50 (d, J¼3.3 Hz,1H), 2.44 (dd,
IR (neat) 2933, 2859, 2786, 1733, 1443, 1119, 845, 701 cmꢁ1
;
1H
J¼3.3 and 1.7 Hz, 1H), 3.76 (s, 3H), 2.64 (t, J¼5.9 Hz, 2H), 2.56 (t,
NMR (CDCl3) d 7.33–7.26 (m, 2H), 7.06–7.00 (m, 1H), 2.88 (s, 3H),
2.67–2.48 (m, 2H), 2.35–2.22 (m, 1H), 2.18–2.09 (m, 1H), 1.97–1.85
(m, 2H), 1.63–1.47 (m, 2H), 1.40–1.25 (m, 2H); 13C NMR (CDCl3)
J¼5.9 Hz, 2H), 1.89–1.71 (m, 4H); 13C NMR (CDCl3)
d
149.3 (C), 141.4
(CH), 139.7 (C), 139.6 (C), 113.4 (C), 111.1 (CH), 105.9 (CH), 35.7 (CH3),
22.9 (CH2), 22.5 (CH2), 21.6 (CH2), 21.5 (CH2). HRMS: (FAB) calcd for
C12H14N2O [MþH]þ 203.1184, found 203.1185.
d
148.2 (C), 136.9 (C), 127.4 (CH), 126.5 (CH), 125.8 (CH), 76.0 (CH),
52.5 (CH), 41.2 (CH3), 28.8 (CH2), 28.1 (CH2), 25.8 (CH2), 24.4
(CH2). HRMS: (FAB) calcd for C12H16N2S [M]þ 220.1034, found
220.1030.
4.20. Synthesis of compounds (11d) and (12d)
These compounds were prepared from compound 6d (0.1 g,
0.53 mmol) and methylhydrazine (0.22 mL, 4.23 mmol) using the
same procedure given for 11a. The crude product was purified by
column chromatography on silica (heptane/EtOAc) to yield product
11d (63 mg, 54.9%) as a yellow oil and product 12d (17 mg, 15%) also
as a yellow oil.
4.22.2. 4,5,6,7-Tetrahydro-2-methyl-3-(thiophen-2-yl)-2H-
indazole (9b)
IR (neat) 2928, 2854, 1656, 1443, 1411, 1372, 1058, 846,
698 cmꢁ1
;
1H NMR (CDCl3)
d
7.34 (dd, J¼5.1 and 1.2 Hz, 1H), 7.08–
7.04 (m, 1H), 7.03–7.00 (m, 1H), 3.82 (s, 3H), 2.62 (t, J¼6.1 Hz, 2H),
2.48 (t, J¼6.1 Hz, 2H), 1.81–1.63 (m, 4H); 13C NMR (CDCl3)
d 148.3
(C), 133.0 (C), 131.4 (C), 127.5 (CH), 127.2 (CH), 126.5 (CH), 116.0 (C),
37.6 (CH3), 23.6 (CH2), 23.4 (2ꢂCH2), 21.6 (CH2). HRMS: (FAB) calcd
for C12H14N2S [MþH]þ 219.0956, found 219.0960.
4.20.1. 3,3a,4,5,6,7-Hexahydro-2-methyl-3-(1-methyl-1H-pyrrol-2-
yl)-2H-indazole (11d)
IR (neat) 2931, 2856, 2777, 1624, 1497, 1446, 1291, 708 cmꢁ1; 1H
NMR (CDCl3)
2.70–2.57 (m, 5H), 2.22–2.05 (m, 2H), 2.02–1.92 (m, 1H), 1.88–1.79
(m, 1H), 1.53–1.18 (m, 4H); 13C NMR (CDCl3)
156.8 (C), 129.1 (C),
d
6.59 (t, J¼2.2 Hz, 1H), 6.13–6.04 (m, 2H), 3.67 (s, 3H),
4.23. 4,5,6,7-Tetrahydro-1-methyl-3-phenyl-1H-
indazole (12a)33
d
123.8 (CH), 109.2 (CH), 107.0 (CH), 73.4 (CH3), 52.8 (CH), 42.4 (CH3),
35.1 (CH), 32.2 (CH2), 27.8 (CH2), 25.9 (CH2), 24.6 (CH2). HRMS:
(FAB) calcd for C13H19N3 [MþH]þ 218.1657, found 218.1658.
Compound 8a (0.14 g, 0.65 mmol) was dissolved in dry dioxane
(40 mL) and p-chloranil (0.16 g, 0.65 mmol) was added. The re-
action mixture was heated at reflux temperature overnight. The
resulting black solution was allowed to reach room temperature
and then 20% aq KOH was added. The reaction mixture was
extracted with ether (3ꢂ60 mL) and the combined organic ex-
tracts were washed with water, dried (Na2SO4) and evaporated to
give 12a as a brown oil (0.14 g, 100%). IR (neat) 3059, 2929, 2852,
4.20.2. 4,5,6,7-Tetrahydro-1-methyl-3-(1-methyl-1H-pyrrol-2-yl)-
1H-indazole (12d)
IR (neat) 3100, 2931, 2852, 1691, 1578, 1493, 1458, 715 cmꢁ1; 1H
NMR (CDCl3)
(m, 1H), 3.87 (s, 3H), 3.76 (s, 3H), 2.58 (q, J¼5.8 Hz, 4H), 1.91–1.69
(m, 4H); 13C NMR (CDCl3)
141.2 (C), 139.3 (C), 126.3 (C), 123.7 (CH),
d
6.65 (t, J¼2.2 Hz, 1H), 6.29–6.25 (m, 1H), 6.18–6.14
1732, 1443, 1371, 770, 695 cmꢁ1 1H NMR (CDCl3)
; d 7.68–7.61 (m,
d
2H), 7.35–7.27 (m, 2H), 7.23–7.16 (m, 1H), 3.69 (s, 3H), 2.63 (t,
114.6 (C), 109.4 (CH), 107.4 (CH), 36.1 (CH3), 35.6 (CH3), 23.2 (CH2),
22.6 (CH2), 22.0 (CH2), 21.6 (CH2). HRMS: (FAB) calcd for C13H17N3
[MþH]þ 216.1501, found 216.1497.
J¼6.1 Hz, 2H), 2.51 (t, J¼6.1 Hz, 2H), 1.82–1.62 (m, 4H); 13C NMR
(CDCl3)
d 147.1 (C), 139.9 (C), 134.4 (C), 128.5 (CH), 127.1 (CH),
126.7 (CH), 113.8 (C), 35.6 (CH3), 23.4 (CH2), 22.5 (2ꢂCH2), 21.7
(CH2). HRMS: (FAB) calcd for C14H16N2 [MþH]þ 213.1392, found
213.1392.
4.21. Synthesis of compounds (8a) and (9a)
These compounds were prepared from compound 2b (0.51 g,
2.74 mmol) and methylhydrazine (1.17 mL, 21.94 mmol) using the
same procedure given for compound 11a. The crude product was
purified by column chromatography on silica (heptane/EtOAc),
which gave 0.27 g (46%) of product 8a as a yellow oil and 0.12 g
(20.6%) of product 9a also as a yellow oil.
4.24. 4,5,6,7-Tetrahydro-2-methyl-3-phenyl-2H-
indazole (9a)30
This compound was prepared from compound 11a (0.3 g,
1.4 mmol) and DDQ (0.3 g, 1.4 mmol) using the same procedure
given for 12a. The product was obtained without further purifica-
tion as a dark yellow oil (0.26 g, 88%). IR (neat) 3057, 2928, 2852,
4.21.1. 3a,4,5,6,7,7a-Hexahydro-1-methyl-3-phenyl-1H-
1678, 1489, 1371, 760, 698 cmꢁ1
;
1H NMR (CDCl3)
d
7.42–7.24 (m,
5H), 3.71 (s, 3H), 2.64 (t, J¼6.2 Hz, 2H), 2.40 (t, J¼6.2 Hz, 2H), 1.84–
1.62 (m, 4H); 13C NMR (CDCl3)
148.2 (C), 139.8 (C), 130.6 (C), 129.2
indazole (8a)29
IR (neat) 2931, 2859, 2783,1496,1443,1175,1117, 928, 758 cmꢁ1
;
d
1H NMR (CDCl3)
2.74–2.59 (m, 1H), 2.54–2.44 (m, 1H), 2.37–2.11 (m, 2H), 1.97–1.83
(m, 2H), 1.67–1.21 (m, 4H); 13C NMR (CDCl3)
157.7 (C), 133.5 (C),
d
7.68–7.61 (m, 2H), 7.42–7.30 (m, 3H), 2.91 (s, 3H),
(CH), 128.7 (CH), 128.2 (CH), 114.9 (C), 37.1 (CH3), 23.7 (CH2), 23.5
(CH2), 23.4 (CH2), 21.3 (CH2). HRMS: (FAB) calcd for C14H16N2
[MþH]þ 213.1392, found 213.1392.
d