96
D. Saha et al. / Journal of Organometallic Chemistry 776 (2015) 89e97
1
.33e1.08 (m,11H, Cy-H). 13C NMR (CDCl
3
,125.8 MHz, ppm).
d
147.9,
6H, eCH
3
), 1.94e1.92 (m, 2H, Cy-H), 1.83e1.65 (m, 10H, Cy-H),
1
3
47.7, 134.1, 133.9, 133.6, 129.3, 127.5, 127.2, 123.4, 108.4, 34.4, 34.3,
0.5, 30.4, 29.3, 29.2, 27.5, 27.4, 27.3, 27.2, 26.7, 26.5; P NMR
1.42e1.37 (m, 2H, Cy-H), 1.32e1.24 (m, 4H, Cy-H), 1.19e1.11 (m,
31
13
2H, Cy-H); C NMR (CDCl
3
, 125.8 MHz, ppm)
d
141.8 (J ¼ 8.8 Hz),
(
CDCl
3
, 202.44 MHz, ppm).
d
ꢁ14.08 (s); HRMS (ESI) m/z calculated
137.3, 133.5, 132.7, 130.0, 130.0, 128.0, 126.3 (J ¼ 32.5 Hz), 36.3
þ
31
for C22
C
H31NP [MþH] 340.2194, found 340.2186; Anal. calcd for
(J ¼ 26.3 Hz), 29.1, 29.0, 27.2, 27.1, 27.1, 27.0, 25.9, 16.7. P NMR
22
H
30NP C, 77.84; H, 8.91; N, 4.13; found C, 77.08; H. 8.91; N, 4.03.
3
(CDCl , 202.44 MHz, ppm). d 33.50 (s); Anal. calcd for
24 2
C H34Cl NPPd. C, 52.91; H, 6.29; N, 2.57; found C, 51.88; H. 6.24; N,
1-(2-(Diphenylphosphino)phenyl)-1H-pyrrole (L6)
2.46.
To a stirred solution of 1-(2-bromophenyl)-1H-pyrrole (1k)
Typical procedure for the SuzukieMiyaura cross-coupling reaction
(
349.3 mg, 1.78 mmol) in THF (6 mL) under argon atmosphere was
ꢀ
added n-BuLi (1.3 mL, 2.13 mmol, 1.6 M in THF) drop wise at ꢁ78 C.
2 3
A solution of ligand (L) (2/4 mol%), Pd (dba) (1 mol%), chlor-
The mixture was slowly warmed to rt and then stirred for further ½
oarene (0.75 mmol), arylboronic acid (1.125 mmol), and CsF
ꢀ
h at rt. After the mixture was cooled to ꢁ78 C, chloro diphenyl-
(
341.7 mg, 2.25 mmol) in toluene (1.5 mL) was stirred under argon
phosphine (0.4 mL, 2.13 mmol) was added and stirring was
ꢀ
atmosphere at 100 C for 5e6 h (depending on the substrate). The
reaction mixture was then cooled to rt, filtered through celite and
diluted with diethyl ether (20 mL). The organic layer was succes-
sively washed with cold water (3 ꢂ 10 mL) and brine and dried over
continued for 11 h. It was then quenched with saturated NH
4
Cl
ꢀ
solution at 0 C and extracted with diethyl ether (2 ꢂ 30 mL). The
combined organic layer was washed with water and brine and
2 4
dried over anhydrous Na SO . Evaporation of the solvent under
reduced pressure gave the crude product. Purification by flash
column chromatography (Silica gel 230e400 mesh, 1% ethyl ace-
2 4
anhydrous Na SO . The solvent was removed under reduced pres-
sure and the residue was purified by flash chromatography on silica
gel (230e400 mesh) with 1e10% ethyl acetate in petroleum ether
or petroleum ether alone as eluent.
tate/petroleum ether) afforded ligand (L6) as a colorless liquid
1
(
5
272 mg, 53%). R
00.1 MHz, ppm).
f
(petroleum ether) 0.27; H NMR (CDCl
3
,
d
7.39 (t, J ¼ 7 Hz, 1H, AreH), 7.34e7.30 (m, 7H,
Typical procedure for the Hiyama cross-coupling reaction
AreH), 7.27e7.21 (m, 5H, AreH), 7.03 (dd, J ¼ 7.5 Hz, 3 Hz, 1H,
AreH), 6.65 (d, J ¼ 1.5 Hz, 2H, eCH of pyrrole), 6.19 (t, J ¼ 2 Hz, 2H,
2
A solution of ligand (L) (3/6 mol%), Pd(OAc) (3 mol%), chlor-
eCH of pyrrole); 13C NMR (CDCl
, 125.8 MHz, ppm). d 145.9, 145.7,
3
oarene (0.75 mmol), phenyltrimethoxy silane (1.125 mmol), and
TBAF (1.1 mL) in dioxane (2.0 mL) was stirred under argon atmo-
1
1
1
C
C
37.1, 137.0, 134.9, 134.8, 134.0, 133.9, 133.5, 129.8, 128.9, 128.7,
31
28.6, 128.5, 128.4, 127.8, 127.0, 123.0, 123.0, 109.0; P NMR (CDCl
3
,
ꢀ
sphere at 100 C for 4e8 h (depending on the substrate). The re-
61.99 MHz, ppm).
d
ꢁ16.35 (s); HRMS (ESI) m/z calculated for
action mixture was then cooled to rt, filtered through celite and
diluted with diethyl ether (20 mL). The organic layer was succes-
sively washed with cold water (3 ꢂ 10 mL) and brine and dried over
þ
22
H19NP [MþH] 328.1255, found 328.1252; Anal. calcd for
22
H18NP C, 80.72; H, 5.54; N, 4.28; found C, 79.65; H. 5.57; N, 4.18.
2 4
anhydrous Na SO . The solvent was removed under reduced pres-
Procedure for synthesis of Pd-L1 complex (I)
sure and the residue was purified by flash chromatography on silica
gel (230e400 mesh) with 1e10% ethyl acetate in petroleum ether
or petroleum ether alone as eluent.
3 2 2
A solution of L1 (368.5 mg, 1 mmol) and Pd(CH CN) Cl
259.4 mg, 1 mmol) in dichloromethane (5 mL) was stirred for
(
2
0 min at rt. The color of the solution changed into yellow. The
4
-Acetylbiphenyl (4a)
solvent was removed under reduced pressure. The residue was
rinsed with hexane and dried in vacuo, affording I as yellow pow-
der (505 mg, 93%), which was crystallized from dichloromethane/
1
[
24] H NMR (300 MHz, CDCl
3
, ppm)
d
8.04 (d, J ¼ 8.4 Hz, 2H),
13
7
(
1
.70e7.62 (m, 4H), 7.47e7.40 (m, 3H), 2.64 (s, 3H); C NMR
75 MHz, CDCl , ppm) 197.8, 145.8,139.9,135.9, 129.0,129.0, 128.3,
27.3, 127.3, 26.7.
ꢀ
1
petroleum ether; mp > 200 C; H NMR (CD
7.74 (t, J ¼ 8 Hz, 1H, AreH), 7.67 (t, J ¼ 8 Hz, 1H, AreH), 7.61 (t,
J ¼ 7.5 Hz, 1H, AreH), 7.47 (dd, J ¼ 8 Hz, 3.5 Hz, 1H, AreH), 6.43 (s,
H, eCH of pyrazole), 5.34 (s, 2H, CH Cl ), 2.86 (s, 3H, eCH ), 2.32
s, 3H, eCH ), 2.10e1.63 (m,15H, Cy-H),1.29e1.18 (m, 7H, Cy-H);
Cl , 125.8 MHz, ppm). 154.9, 144.0, 140.1, 140.0, 131.9,
2 2
Cl , 500.1 MHz, ppm)
3
d
d
1
(
2
2
3
13
4-Methoxybiphenyl (4b)
3
C
NMR (CD
2
2
d
1
[
24] H NMR (300 MHz, CDCl
3
, ppm)
d
7.48e7.43 (m, 4H), 7.32 (t,
1
2
d
31.4, 129.0, 128.9, 126.6, 126.5, 121.6, 113.0, 36.2, 28.9, 28.0, 27.4,
7.4, 27.3, 27.2, 25.9, 16.2, 14.2. P NMR (CD
31
J ¼ 7.2 Hz, 2H), 7.21 (t, J ¼ 7.2 Hz,1H), 6.89 (d, J ¼ 8.8 Hz, 2H), 3.75 (s,
2 2
Cl , 202.44 MHz, ppm).
13
3
H); C NMR (75 MHz, CDCl
3
, ppm) d 159.3, 140.9, 133.9, 128.9,
29.12 (s); Anal. calcd for C23 PPd. C, 50.61; H, 6.09; N, 5.13;
2 2
H33Cl N
128.3, 126.9, 126.8, 114.3, 55.5.
found C, 49.68; H. 5.99; N, 5.19. After repeated attempts, a crystal
suitable for diffraction studies was grown from dichloromethane/
petroleum ether. Details of crystal structure determination are
provided in the supporting information.
4
-Methylbiphenyl (4c)
1
[
15] H NMR (300 MHz, CDCl
3
, ppm)
d
7.60 (d, J ¼ 7.6 Hz, 2H),
7
.53 (d, J ¼ 7.0 Hz, 2H), 7.44 (t, J ¼ 7.2 Hz, 2H), 7.35 (d, J ¼ 6.7 Hz,1H),
Procedure for synthesis of Pd-L3 complex (II)
13
7.26 (d, J ¼ 7.5 Hz, 2H), 2.41 (s, 3H); C NMR (75 MHz, CDCl
3
, ppm)
d
141.3, 138.5, 137.2, 129.7, 128.9, 127.2127.2, 21.3.
A solution of L3 (367.5 mg, 1 mmol) and Pd(CH
259.4 mg, 1 mmol) in dichloromethane (5 mL) was stirred for
0 min at rt. The color of the solution changed into red. The solvent
3 2 2
CN) Cl
(
2
3-Phenylpyridine (4d)
was removed under reduced pressure. The residue was rinsed with
hexane and dried in vacuo, affording II as red powder (495 mg,
[24] 1H NMR (300 MHz, CDCl
, ppm) d 8.85 (s, 1H), 8.59 (d,
3
ꢀ
1
9
1%), which was crystallized from acetone/hexane; mp > 200 C; H
NMR (CDCl , 500.1 MHz, ppm) 7.86e7.81 (m, 3H, AreH), 7.74e7.71
m, 2H, AreH), 7.24 (s, 1H, AreH), 2.73e2.66 (m, 2H, Cy-H), 1.95 (s,
J ¼ 3.2 Hz, 1H), 7.87 (d, J ¼ 7.6 Hz, 1H), 7.57 (d, J ¼ 6.9 Hz, 2H),
13
3
d
3
7.50e7.35 (m, 4H); C NMR (75 MHz, CDCl , ppm) d 148.5, 148.3,
(
137.9, 136.8, 134.5, 129.2, 128.2, 127.2, 123.7.