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154.3, 131.1,128.4, 125.0,112.4, 111.8, 102.5, 102.4, 56.0. 55 loading at 150 °C. Pure decarbonylated product was
GC–MS (m/z): 147.2 [M]+.
1H–Indole (Scheme 2, entry 18). Decarbonylation was
done by general procedure
carbaldehyde (0.12 mmol, 17.4 mg), and
isolated by column chromatography through a silica gel
column (mesh 100–200). Yellow liquid 1–p–Tolyl–1H–
indazole was eluted by pet ether: ethyl acetate mixture
A
with 1H–indole–3–
mol%
1
5
7
(98:2 v/v). Isolated yield 79% (19.7 mg). H NMR (400
palladium acetate (0.0084 mmol, 1.9 mg) loading at 150
°C. Pure decarbonylated product was isolated by column
chromatography through a silica gel column (mesh 100–
200). White crystalline solid 1H–indole was eluted by pet
10 ether: ethyl acetate mixture (98:2 v/v). Isolated yield 78%
1
(11 mg). H NMR (400 MHz, CDCl3) δ: 8.15 (brs, 1H),
60 MHz, CDCl3) δ: 8.18 (s, 1H), 7.79 (dd, 1H, J= 7.8, 1.5),
7.71 (d, 2H, J= 8.6), 7.49 (m, 1H), 7.42 (m, 2H), 7.31 (m,
1H), 7.20 (m, 1H), 2.43 (s, 3H). 13C NMR (100 MHz,
CDCl3) δ: 139.0, 137.9, 136.8, 135.3, 130.2, 127.2, 125.4,
122.9, 121.6, 121.5, 110.6, 21.3. GC–MS (m/z): 208.2
65 [M]+.
7.66–7.64 (m, 1H), 7.41–7.38 (m, 1H), 7.21–7.18 (m, 2H),
7.14–7.10 (m, 1H), 6.57–6.55 (m, 1H). 13C NMR (100
MHz, CDCl3) δ: 135.9, 128.0, 124.2, 122.2, 120.9, 119.9,
15 111.2, 102.8. GC–MS (m/z): 117.1 [M]+.
Same reaction was carried out at 1 mmol scale (145.16
mg). Isolated yield 85% (100 mg).
3–Phenylpropanal
(Scheme
2,
entry
19).
Decarbonylation was done by general procedure A with 3–
20 phenylpropanal (0.12 mmol, 16 µL) and 16 mol%
palladium acetate (0.02 mmol, 4.3 mg) loading at 150 °C.
Yield was determined by gas chromatography using
naphthalene as internal standard. GC yield 43%.
1–p–tolyl–1H–pyrrolo[2,3–b]pyridine–5–carbaldehyde.
70 Following general procedure B, p–tolyl iodide (1.5 mmol,
327 mg); 7–azaindole–5–carbaldehyde (1.5 mmol, 219
mg); CuI (0.3 mmol, 28 mg); 1,10–phenanthrolene (0.6
mmol, 59 mg) and K2CO3 (3 mmol, 414 mg) were used.
Column chromatography provided the desired compound
75 as white solid using pet ether: ethyl acetate mixture (80:20
v/v) as eluent. 1H NMR (400 MHz, CDCl3) δ: 10.06 (s,
1H), 8.62 (dd, 1H, J= 7.9, 1.6), 8.45 (dd, 1H, J= 4.7, 1.6),
8.08 (s, 1H), 7.59 (d, 2H, 8.3), 7.36 (d, 2H, J= 8.2), 7.30
(dd, 1H, J= 7.9, 4.7), 2.44 (s, 3H). 13C NMR (100 MHz,
80 CDCl3) δ: 185.1, 148.8, 145.8, 138.3, 137.9, 134.6, 130.9,
130.4, 124.6, 119.6, 118.2, 117.5, 21.3. GC–MS (m/z):
236.1 [M]+.
1–p–Tolyl–1H–pyrrolo[2,3–b]pyridinepyrazole (Scheme
2, entry 22). Decarbonylation was done by general
85 procedure A with 1–p–tolyl–1H–pyrrolo[2,3–b]pyridine–
5–carbaldehyde (0.12 mmol, 28 mg), and 16 mol%
palladium acetate (0.02 mmol, 4.3 mg) loading at 150 °C.
Pure decarbonylated product was isolated by column
chromatography through a silica gel column (mesh 100–
90 200). Yellow oily liquid 1–p–Tolyl–1H–pyrrolo[2,3–
b]pyridinepyrazolewas eluted by pet ether: ethyl acetate
mixture (93:7 v/v). Isolated yield 70% (17.4 mg). 1H NMR
(400 MHz, CDCl3) δ: 8.40 (s, 1H), 8.00 (m, 1H), 7.61 (m,
2H), 7.50 (m, 2H), 7.35 (m, 2H), 7.13 (m, 1H), 6.63 (m,
95 1H), 2.42 (s, 3H). 13C NMR (100 MHz, CDCl3) δ: 143.8,
141.2, 136.7, 136.5, 130.2, 129.2, 128.3, 124.3, 121.6,
116.8, 101.5, 21.3. GC–MS (m/z): 208.2 [M]+.
Ethene–1,1–diyldibenzene (Scheme 2, entry 20).
25 Decarbonylation was done by general procedure A with
3,3–diphenylacrylaldehyde (0.12 mmol, 25 mg) and 7
mol% palladium acetate (0.0084 mmol, 1.9 mg) loading at
150 °C. Pure decarbonylated product was isolated by
column chromatography through a silica gel column (mesh
30 100–200). Yellow liquid ethene–1,1–diyldibenzenewas
1
eluted by pet ether only. Isolated yield 93% (20 mg). H
NMR (400 MHz, CDCl3) δ: 7.35–7.27 (m, 10H), 5.45 (s,
2H). 13C NMR (100 MHz, CDCl3) δ: 150.2, 141.6, 128.4,
128.3, 127.9, 114.5. GC–MS (m/z): 180.2 [M]+.
35
1–p–Tolyl–1H–indazole–5–carbaldehyde.
Following
general procedure B, p–tolyl iodide (1.5 mmol, 327 mg);
40 1H–indazole–5–carbaldehyde (1.5 mmol, 219 mg); CuI
(0.3 mmol, 28 mg); 1,10–phenanthrolene (0.6 mmol, 59
mg) and K3PO4 (3 mmol, 637 mg) were used. Column
chromatography provided the desired product as white
crystalline solid using pet ether: ethyl acetate mixture (95:5
3–Methyl–1–phenyl–1H–pyrazole (Scheme 2, entry 23).
Decarbonylation was done by general procedure A with 3–
1
45 v/v) as eluent. H NMR (400 MHz, CDCl3) δ: 10.08 (s,
1H), 8.35–8.32 (m, 2H), 7.97 (dd, 1H, J= 8.8, 1.5), 7.77–
7.75 (m, 1H), 7.60–7.51 (m, 2H), 7.38–7.36 (m, 2H), 2.45
(s, 3H). 13C NMR (100 MHz, CDCl3) δ: 191.6, 141.4,
137.8, 137.1, 131.2, 130.4, 127.6, 126.2, 125.1, 123.3,
50 111.4, 21.3. GC–MS (m/z): 236.1 [M]+.
1–p–Tolyl–1H–indazole (Scheme 2, entry 21).
Decarbonylation was done by general procedure A with 1–
p–tolyl–1H–indazole–5–carbaldehyde (0.12 mmol, 28 mg),
and 16 mol% palladium acetate (0.02 mmol, 4.3 mg)
100 methyl–1–phenyl–1H–pyrazole–4–carbaldehyde
(0.12
mmol, 22 mg) and 16 mol% palladium acetate (0.02 mmol,
4.3 mg) loading at 150 °C. Pure decarbonylated product
was isolated by column chromatography through a silica
gel column (mesh 100–200). Colorless liquid 3–methyl–
105 1–phenyl–1H–pyrazolewas eluted by pet ether: ethyl
acetate mixture (99:1 v/v). Isolated yield 58% (11 mg). 1H
NMR (400 MHz, CDCl3) δ: 7.78 (d, 1H, J= 2.2), 7.64–7.62
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