Z. Xi et al.
2,4,6-Tris(3-bromophenyl)-3,7-bis[4-(trifluoromethyl)phenyl]-1H-pyrrolo-
[3,2-c]pyridine (1h): White solid, isolated yield: 42% (365 mg). 1H NMR
was purified by column chromatography (silica gel, hexane/ethyl acetate
(10:1) as eluent) to afford 1q as a white solid.
N
(300 MHz, CDCl3, 258C, TMS): d=6.91–7.77 (m, 20H), 8.46 ppm (s,
1H); 13C NMR (75 MHz, CDCl3, 258C, TMS): d=115.38, 117.11, 121.50,
122.24, 122.92, 124.95, 125.00, 126.46, 126.51, 126.56, 126.60, 127.61,
127.85, 128.97, 129.28, 130.37, 130.55, 130.61, 130.77, 130.90, 131.13,
131.79, 132.85, 132.92, 133.37, 135.68, 137.39, 139.09, 140.64, 140.68,
141.69, 147.35, 151.84 ppm; HRMS: m/z: calcd for C39H21N2F6Br2:
869.9139; found: 869.9146; elemental analysis calcd (%) for
C39H21N2F6Br2: C 53.76, H 2.43, N 3.22; found: C 53.60, H 2.68, N 3.00.
2,4,6-Tris(biphenyl-3-yl)-3,7-diphenyl-1H-pyrrolo
G
(1q):
White solid, isolated yield: 82% (300 mg); m.p. >3008C. 1H NMR
(300 MHz, CDCl3, 258C, TMS): d=6.95–7.66 (m, 37H), 8.51 ppm (s,
1H); 13C NMR (75 MHz, CDCl3, 258C, TMS): d=116.31, 117.79, 121.43,
125.74, 126.05, 126.30, 126.68, 126.80, 126.91, 126.94, 126.98, 127.12,
127.21, 127.47, 127.67, 127.80, 128.23, 128.27, 128.46, 128.51,128.69,
129.02, 129.43, 129.52, 129.62, 130.27, 130.83, 132.28, 134.48, 136.15,
136.25, 139.87, 140.02, 140.16, 140.29, 140.77, 141.06, 141.13, 141.34,
141.35, 147.88, 152.81 ppm; HRMS: m/z: calcd for C55H38N2: 726.3035;
found: 726.3022; elemental analysis calcd (%) for C55H38N2: C 90.88, H
5.27, N 3.85; found: C 90.72, H 5.30, N 5.08.
2,4,6-Tri(thiophen-2-yl)-3,7-di-p-tolyl-1H-pyrrolo
G
(1j):
Yellow solid, isolated yield: 50% (272 mg); m.p. 2568C. 1H NMR
(300 MHz, CDCl3, 258C, TMS): d=2.40 (s, 3H), 2.51 (s, 3H), 6.19–6.26
(m, 1H), 6.50–6.64 (m, 2H), 6.76–6.84 (m, 1H), 6.88–6.96 (m, 2H), 7.04–
7.32 (m, 7H), 7.32–7.50 (m, 4H), 8.13 ppm (s, 1H); 13C NMR (75 MHz,
CDCl3, 258C, TMS): d=21.37, 21.49, 115.40, 116.24, 119.95, 125.69,
125.78, 126.20, 126.39, 126.58, 126.62, 126.82, 127.09, 127.28, 128.70,
128.73, 128.83, 128.87, 128.94, 129.10, 129.15, 129.20, 129.50, 129.62,
129.82, 129.88, 130.00, 130.07, 130.56, 130.92, 131.31, 131.68, 132.11,
133.59, 137.25, 138.56, 141.34, 142.14, 143.39, 145.30, 145.65 ppm; HRMS:
m/z: calcd for C33H24N2S3: 544.1102; found: 544.1111.
2,4,6-Tris(biphenyl-4-yl)-3,7-diphenyl-1H-pyrrolo
(1p):
White solid, isolated yield: 53% (385 mg); m.p. >3008C. 1H NMR
(300 MHz, CDCl3, 258C, TMS): d=6.70–7.91 (m, 37H), 8.51 ppm (s,
1H); 13C NMR (75 MHz, CDCl3, 258C, TMS): d=116.23, 117.61, 121.70,
125.77, 125.81, 126.11, 126.37, 126.92, 127.00, 127.04, 127.09, 127.12,
127.22, 127.61, 127.77, 127.84, 128.64, 128.67, 128.74, 128.85, 129.38,
129.91, 130.22, 130.79, 130.92, 131.00, 134.66, 135.63, 136.13, 138.50,
139.50, 139.61, 139.92, 140.14, 140.65, 140.97, 141.11, 141.46, 147.61,
152.55 ppm; HRMS: m/z: calcd for C55H38N2: 726.3035; found: 726.3096.
2,4,6-Tricyclopropyl-3,7-diphenyl-1H-pyrroloACHTUNGETRN[UNNG 3,2-c]pyridine (1l): White
1
solid, isolated yield: 71% (277 mg); m.p. 150–1518C. H NMR (300 MHz,
CDCl3, 258C, TMS): d=0.51–0.53 (m, 2H), 0.59–0.74 (m, 4H), 0.74–0.85
(m, 2H), 0.97–1.08 (m, 2H), 1.08–1.20 (m, 2H), 1.62–2.07 (m, 3H), 6.89–
7.91 ppm (m, 11H); 13C NMR (75 MHz, CDCl3, 258C, TMS): d=7.10,
7.81, 9.07, 9.22, 13.58, 14.42, 115.42, 115.59, 120.78, 126.47, 127.39, 127.70,
129.02, 130.28, 131.33, 136.13, 136.36, 138.22, 148.63, 153.30 ppm; HRMS:
m/z: calcd for C28H26N2: 390.2096; found: 390.2088.
Formation of pyrrole derivatives 3a–d from one silicon-tethered diyne
and two identical organonitriles—general procedure for the preparation
of 1-(5-sec-butyl-2-benzyl-4-phenyl-1H-pyrrol-3-yl)-2-methylbutan-1-one
(3b): nBuLi (2.1 mmol, 1.6m, 1.32 mL) was added dropwise through a sy-
ringe to a toluene (10 mL) solution of [Cp2ZrCl2] (1.05 mmol, 307 mg) at
À788C (dry ice/acetone) in a 20 mL Schlenk tube. After the addition, the
reaction mixture was stirred at À788C for 1 h. Then bis(phenylethynyl)di-
methylsilane (2a; 1 mmol) was added and the reaction mixture was
warmed to 508C and stirred at this temperature for 3 h. Isobutyronitrile
(1.5 mmol, 0.135 mL) was then added and the reaction mixture was
stirred at this temperature for 1 h. The reaction mixture was quenched
with a saturated aqueous solution of NaHCO3 and the resulting mixture
was extracted with diethyl ether three times and then washed with water
and brine. The extract was dried over anhydrous MgSO4. The solvent was
evaporated in vacuo to give a yellow solid, which was subjected to SiO2
column chromatography using hexane/diethyl ether (1:1) as the eluent.
The characterisation data for compound 3a has been published in our
previous communication.[9a]
2,4,6-Tricyclohexyl-3,7-diphenyl-1H-pyrroloACHTUNGRETN[UNNG 3,2-c]pyridine (1m): White
1
solid, isolated yield: 59% (305 mg); m.p. 244–2458C. H NMR (300 MHz,
CDCl3, 258C, TMS): d=0.46–0.96 (m, 2H), 0.96–1.42 (m, 9H), 1.42–2.13
(m, 19H), 2.31–2.93 (m, 3H), 7.00–7.58 (m, 10H), 7.62 ppm (s, 1H);
13CNMR (75 MHz, CDCl3, 258C, TMS): d=25.74, 26.18, 26.29, 26.47,
26.60, 26.66, 32.23, 33.11, 33.21, 33.39, 35.60, 41.52, 41.71, 113.30, 115.28,
116.62, 126.80, 127.32, 127.78, 128.94, 129.96, 131.22, 136.68, 136.73,
138.48, 140.57, 153.12, 157.84 ppm; HRMS: m/z: calcd for C37H42N2:
516.3505; found: 516.3506.
2,4,6-Tris(4-bromophenyl)-3,7-diphenyl-1H-pyrroloACHTNUTRGNEUNG[3,2-c]pyridine (1n):
White solid, isolated yield: 61% (448 mg). 1H NMR (300 MHz, CDCl3,
258C, TMS): d=6.86–7.72 (m, 22H), 8.42 ppm (s, 1H); 13C NMR
(75 MHz, CDCl3, 258C, TMS): d=116.78, 118.34, 121.33, 121.56, 121.94,
122.62, 126.94, 127.33, 128.04, 128.10, 128.26, 128.63, 129.04, 129.51,
130.03, 130.07, 130.10, 130.44, 130.53, 130.96, 131.13, 132.74, 133.34,
133.56, 133.66, 134.83, 135.14, 140.96, 141.05, 142.34, 146.73, 151.42 ppm;
HRMS: m/z: calcd for C37H23Br3N2: 733.9391; found: 733.9388; elemental
analysis calcd (%) for C37H23Br3N2: C 60.44, H 3.15, N 3.81; found: C
88.61, H 6.06, N 5.00.
1-(5-sec-Butyl-2-benzyl-4-phenyl-1H-pyrrol-3-yl)-2-methylbutan-1-one
(3b): White solid, isolated yield: 50% (160 mg); m.p. 1258C. 1H NMR
(300 MHz, CDCl3, 258C, TMS): d=0.48–0.61 (m, 3H), 0.61–0.74 (m,
3H), 0.78–0.86 (m, 3H), 0.95–1.10 (m, 3H), 1.10–1.60 (m, 4H), 2.21–2.46
(m, 1H), 2.46–2.67 (m, 1H), 4.00–4.43 (s, 2H) 7.90 ppm (s,1H); 13C NMR
(75 MHz, CDCl3, 258C, TMS): d=11.64, 11.70, 11.97, 12.03, 15.87, 15.90,
16.29, 16.33, 20.89, 20.91, 26.39, 26.43, 26.75, 29.93, 29.99, 31.74, 33.84,
44.44, 44.51, 121.09, 121.19, 121.25, 126.58, 126.60, 127.98, 128.75, 128.97,
130.68, 132.64, 132.67, 132.69, 135.04, 135.06, 136.71, 136.75, 138.56,
204.54 ppm; HRMS: m/z: calcd for C26H31NO: 373.2406; found:
373.2408.
2,4,6-Tris(3-bromophenyl)-3,7-diphenyl-1H-pyrroloACHTNUTRGNEUNG[3,2-c]pyridine (1o):
White solid, isolated yield: 58% (404 mg). 1H NMR (300 MHz, CDCl3,
258C, TMS): d=6.86–7.48 (m, 22H), 8.38 ppm (s, 1H); 13C NMR
(75 MHz, CDCl3, 258C, TMS): d=116.35, 117.88, 121.53, 121.80, 122.47,
126.62, 128.01, 128.16, 129.04, 129.54, 129.89, 130.02, 130.09, 130.57,
130.78, 130.85, 131.02, 131.87, 132.05, 133.98, 135.14, 135.46, 138.11,
139.27, 141.07, 146.99, 151.73 ppm; HRMS: m/z: calcd for C37H23Br3N2:
733.9391; found: 733.9385; elemental analysis calcd (%) for C37H23Br3N2:
C 60.44, H 3.15, N 3.81; found: C 88.61, H 6.06, N 5.00.
1-(5-sec-Butyl-2-p-tolylmethyl-4-p-tolyl-1H-pyrrol-3-yl)-2-methylbutan-1-
one (3c): Yellow solid, isolated yield: 40% (187 mg); m.p. 118–1208C.
1H NMR (300 MHz, CDCl3, 258C, TMS): d=0.45–0.64 (m, 3H), 0.64–
0.75 (m, 3H), 0.75–0.92 (m, 3H), 0.92–1.09 (m, 3H), 1.09–1.21 (m, 1H),
1.22–1.42 (m, 2H), 1.42–1.66 (m, 1H), 2.18–2.36 (s, 3H), 2.36–2.45 (s,
3H), 2.45–2.66 (m, 2H), 3.96–4.61 (s, 2H), 6.63–7.50 (m, 8H), 8.09 ppm
(s, 1H); 13C NMR (75 MHz, CDCl3, 258C, TMS): d=11.66, 11.72, 12.00,
12.07, 15.96, 16.38, 20.94, 21.07, 21.23, 26.51, 26.78, 29.91, 29.97, 31.73,
33.51, 44.27, 44.33, 120.92, 121.00, 121.14, 128.67, 128.90, 129.44, 130.52,
132.55, 133.63, 133.66, 135.35, 135.40, 136.04, 136.08, 204.60 ppm; HRMS:
m/z: calcd for C28H35NO: 401.2719; found: 401.2718.
Formation of pyrroloACHTUNGTRENNUNG[3,2-c]pyridine derivatives (5-azaindoles) 1p and 1q
by Suzuki coupling of 1n and 1o and benzeneboronic acid—typical pro-
cedure for the preparation of 2,4,6-tri(biphenyl-3-yl)-3,7-diphenyl-1H-
pyrroloACHTUNGTRENNUNG[3,2-c]pyridine (1q): A solution of potassium carbonate (690 mg,
5.0 mmol) in water (2.5 mL) was added to a mixture of 1o (368 mg,
0.5 mmol) and benzeneboronic acid (244 mg, 2.0 mmol) in THF (5 mL).
After degassing the mixture and backfilling with nitrogen, [PdACTHUNRTGNEUNG(PPh3)4]
(29 mg, 0.025 mmol) was added and then the reaction mixture was
heated at reflux for 16 h. The mixture was extracted with dichlorome-
thane and washed with brine (3ꢂ100 mL). The organic extracts were
dried with anhydrous MgSO4. After removal of the solvent, the residue
[2-Benzyl-4-phenyl-5-(1-phenylcyclopropyl)-1H-pyrrol-3-yl](1-phenylcy-
clopropyl)methanimine (3d): Yellow solid, isolated yield: 53% (260 mg);
m.p. 166–1678C. H NMR (300 MHz, CDCl3, 258C, TMS): d=0.87 (t, J=
6.3 Hz, 2H), 0.95 (t, J=6.9 Hz, 2H), 1.85 (t, J=7.2 Hz, 2H), 1.31 (t, J=
7.2 Hz, 2H), 3.45 (s, 2H), 6.63–6.78 (m, 2H), 6.88–6.99 (m, 2H), 7.06–
7.32 (m, 16H), 7.42 (s, 1H), 7.65 ppm (s, 1H); 13C NMR (CDCl3, TMS):
1
12614
ꢀ 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Eur. J. 2009, 15, 12608 – 12617