Organometallics
Article
24PS,
+
even lead to new transformations such as distal ring-closing
opportunities relevant in the one-pot construction of
catenanes/rotaxanes, for instance.
δ 51.8 (1P). HRMS (+ESI) m/z: (M + H) calcd for C22
51.1336; found, 351.1341.
′. White solid. Mp: 273.8- 274.3 °C. H NMR (CDCl , 400
H
3
1
3
3
MHz): δ 7.78−7.73 (m, 4H, Ar), 7.47−7.45 (m, 4H, Ar), 7.43−7.43
(
m, 2H, Ar), 7.41−7.39 (m, 4H, Ar), 7.19−7.15 (m, 6H, Ar), 5.21 (d,
EXPERIMENTAL SECTION
2 13
■
1
2
1
H, J = 11.6 Hz, PCH). C NMR (CDCl , 126 MHz): δ 136.9 (d,
P
H
3
General Information. All reactions were carried out under a
positive pressure of nitrogen using standard Schlenk techniques.
Solvents were purchased from their respective companies (ACN,
MeOH, DCM, VWR Chemicals; DEE, Merck; toluene, n-hexane,
Avantor; acetone, Sigma-Aldrich; THF, Tedia) and distilled under an
atmosphere of nitrogen prior to use. A PSL-1400 Low Temp
Pairstirrer was used for controlling low-temperature reactions.
Column chromatography was done on silica gel 60 (Merck). Melting
points were measured using an SRS MPA100 Optimelt Automated
Point System. NMR spectra were recorded on Bruker AV 300, AV
2
1
C, J = 2.9 Hz, PCPh ), 132.5 (d, 2C, J = 79.1 Hz, PPhipso),
PC
ipso
PC
4
4
32.2 (d, 4C, J = 3.0 Hz, PCPh ), 131.5 (d, 2C, J = 3.1 Hz,
PC
meta
PC
2
3
PPhpara), 130.4 (d, 4C, J = 6.8 Hz, PPhortho), 128.4 (d, 4C, J
=
PC
PC
5
1
1.9 Hz, PPhmeta), 128.3 (s, 4C, PCPh ), 127.4 (d, 2C, J = 1.7
ortho PC
1
31
1
Hz, PCPhpara), 53.7 (d, 1C, J = 49.1 Hz, H CC). P{ H} NMR
PC
3
+
(
CDCl , 162 MHz): δ 47.3 (1P). HRMS (+ESI) m/z: (M + H)
3
calcd for C H PS, 385.1180; found, 385.1185. Anal. Calcd for
2
5
22
C H PS: C, 78.10; H, 5.51. Found: C, 77.72; H, 5.82.
2
5
21
General Procedure for the Deuteration of C,P-Palladacycle
a. HAsPh (36.0 mg, 0.15 mmol, 5.0 equiv.to Pd) was prestirred in
the stated solvent (2.4 mL) for 2 h at room temperature. Palladacycle
1a (19.50 mg, 0.03 mmol, 1.0 equiv) was added, and the solution was
1
2
4
00, and AV 500 spectrometers. Chemical shifts are reported in ppm
1
and referenced to an internal SiMe standard (0 ppm) for H NMR,
4
1
3
chloroform-d (77.23 ppm) for C NMR, and external 85% H PO for
3
4
31
1
22
22
23
23 21
21
stirred for 30 min at room temperature. S (4.80 mg, 0.15 mmol, 5.0
8
P{ H} NMR. The complexes 1b, 1c, 2b, 3b,
5
and 6
equiv) was subsequently added. After the mixture was stirred for
another 30 min, volatiles were removed and the crude product was
purified by column chromatography (1/1 DCM/hexane) to afford the
pure sulfurized ligand 1′ as a white solid.
were prepared according to literature methods. All other reactants and
reagents were used as supplied.
Synthesis of Metal Perchlorate Complex. The dimeric
complex (1.56 mmol) was dissolved in DCM (80 mL) and MeCN
1
′ (Deuterated). White solid. Mp: 72.9−73.9 °C. 1H NMR
(
5 mL) at room temperature. Following the addition of a solution of
(
CDCl , 300 MHz): δ 8.24−8.16 (m, 2H, Ar), 7.75−7.71 (m, 2H,
AgClO (0.48 g, 2.34 mmol, 1.5 equiv) in H O (2 mL), the solution
3
4
2
Ar), 7.69−7.67 (m, 1H, Ar), 7.62−7.54 (m, 3H, Ar), 7.50−7.47 (m,
was stirred vigorously in the dark for 1 h. The crude product was
1
H, Ar), 7.34−7.29 (m, 1H, Ar), 7.24−7.18 (m, 3H, Ar), 7.07−7.02
passed through a short plug of silica, washed with H O (15 mL × 3),
2
(
3
m, 1H, Ar), 6.91−6.86 (m, 2H, Ar), 4.91 (m, 1H, PCH), 1.70 (dd,
dried over MgSO , and recrystallized from DCM/DEE to give pure
4
3
3
13
H, J = 18.6 Hz, J = 6.9 Hz, CH ); C NMR (CDCl , 75
yellow crystals of complexes 1a, 2a, and 3a. The spectroscopic data
obtained were consistent with the literature.
General Procedure for Protonolysis of C,P-Palladacycles.
PH
HH
3
3
24
2
MHz): δ 133.7−122.1 (14C, Ar), 132.5 (d, 2C,
J
PC = 9.0 Hz,
2
3
PPhortho), 131.5 (d, 2C, JPC = 9.7 Hz, PPhortho), 129.0 (d, 2C, JPC
=
3
HAsPh (36.0 mg, 0.15 mmol, 5.0 equiv.to Pd) was added to a
11.3 Hz, PPhmeta), 127.8 (d, 2C, JPC = 11.9 Hz, PPhmeta), 34.5 (d, 1C,
2
1
31
1
solution of the palladacycle (0.03 mmol, 1.0 equiv) in the stated
solvent (2.4 mL) and stirred for 30 min at room temperature. S (4.80
JPC = 51.0 Hz, H CC), 17.1 (s, 1C, H C); P{ H} NMR (CDCl ,
3
3
3
+
8
162 MHz): δ 52.6 (1P). HRMS (+ESI) m/z: (M + H) calcd for
mg, 0.15 mmol, 5.0 equiv) was subsequently added. After the mixture
was stirred for another 30 min, volatiles were removed and the crude
product was purified by column chromatography (1/1 DCM/hexane)
to afford the pure sulfurized ligands 1′, 2′, and 3′ as white solids.
Colorless crystals of sulfurized ligand 1′ could be recrystallized from
DCM/hexane at −15 °C.
C H DPS, 374.1243; found, 374.1246. Anal. Calcd for C H DPS:
C, 77.18; H, 5.94. Found: C, 77.36; H, 5.61.
General Procedure for Protonolysis of E,C,N-Palladacycles.
2
4
21
24 20
HAsPh (36.0 mg, 0.15 mmol, 5.0 equiv.to Pd) was added to a
2
solution of the palladacycle (0.03 mmol, 1.0 equiv) in DCM (2.4 mL)
and stirred for 30 min at room temperature. Volatiles were removed,
and the crude product was purified by column chromatography (5′,
EA; 6′, 5/1 DCM/hexane) to afford the pure ligands 5′ and 6’ as
white solids. The spectroscopic data obtained were consistent with
1
′ (Protonated). White solid. Mp: 72.8−73.6 °C. 1H NMR
(
CDCl , 500 MHz): δ 8.22−8.18 (m, 2H, Ar), 8.13−8.12 (m, 1H,
3
Ar), 7.75−7.71 (m, 2H, Ar), 7.67−7.66 (m, 1H, Ar), 7.61−7.58 (m,
3
H, Ar), 7.50−7.47 (m, 1H, Ar), 7.33−7.30 (m, 1H, Ar), 7.23−7.18
21
the literature.
(
(
m, 3H, Ar), 7.06−7.03 (m, 1H, Ar), 6.90−6.87 (m, 2H, Ar), 4.91
m, 1H, PCH), 1.70 (dd, 3H, J = 19.0 Hz, J = 7.0 Hz, CH ).
General Procedure for the Attempted Deprotonation of
Palladacycle 1d. Palladacycle 1d (6.50 mg, 0.01 mmol, 1.0 equiv)
3
3
PH
HH
3
13
C NMR (CDCl , 126 MHz): δ 133.7−122.0 (14C, Ar), 132.5 (d,
3
and NEt (14.4 μL, 0.10 mmol, 10.0 equiv) were stirred in CDCl
2
2
3
3
2
1
C, J = 9.1 Hz, PPh ), 131.5 (d, 2C, J = 9.01 Hz, PPh ),
PC ortho PC ortho
3 3
(
0.6 mL) at room temperature for 2 h. The solution was periodically
29.0 (d, 2C, J = 11.2 Hz, PPh ), 127.8 (d, 2C, J = 12.0 Hz,
31
1
PC
meta
PC
monitored by P{ H} NMR spectroscopy, and no conversion of
1
PPh ), 34.5 (d, 1C, J = 51.7 Hz, H CC), 17.1 (s, 1C, H C).
meta
PC
3
3
palladacycle 1d was observed even after 2 h.
31
1
P{ H} NMR (CDCl , 162 MHz): δ 52.6 (1P). HRMS (+ESI) m/z:
3
(
M + H)+ calcd for C H PS, 373.1180; found, 373.1183. Anal.
2
4
22
Calcd for C H PS: C, 77.39; H, 5.68. Found: C, 77.24; H, 5.83.
ASSOCIATED CONTENT
2
4
21
■
1
2
′. White deliquescent solid. H NMR (CDCl , 400 MHz): δ
3
*
S
Supporting Information
8
.15−8.09 (m, 2H, Ar), 7.63−7.56 (m, 4H, Ar), 7.32−7.28 (m, 1H,
Ar), 7.21−7.11 (m, 4H, Ar), 6.95−6.94 (m, 1H, Ar), 6.82−6.80 (m,
H, Ar), 4.17 (m, 1H, PCH), 2.35 (s, 3H, C H), 1.75 (s, 3H,
1
meta
3
3
13
CorthoH), 1.52 (dd, 1H, J = 19.2 Hz, J = 7.2 Hz, CH ).
NMR (CDCl , 75 MHz): δ 135.7 (d, 1C, JPC = 4.6 Hz,
C
PH
HH
3
3
3
2
PCPh
), 135.5 (d, 1C, J = 2.9 Hz, PCPhipso), 133.2
ortho(quaternary)
PC
4
(
d, 1C, 1JPC = 79.0 Hz, PPhipso), 133.2 (d, 1C, JPC = 6.6 Hz,
2
PCPh
), 132.8 (d, 2C, J = 9.0 Hz, PPhortho), 131.9 (d,
meta(quaternary)
PC
4
2
1
1
C, J = 2.8 Hz, PCPh ), 131.6 (d, 2C, J = 9.6 Hz, PPhortho),
31.2 (d, 1C, J = 2.9 Hz, PPh ), 130.5 (d, 1C, J = 74.9 Hz,
PPhipso), 129.9 (d, 1C, JPC = 1.1 Hz, PCPhortho), 129.8 (s, 1C,
PCPhpara), 128.9 (d, 2C, J = 11.4 Hz, PPh ), 128.1 (d, 1C, J =
.0 Hz, PPhpara), 127.9 (d, 2C, J = 11.9 Hz, PPhmeta), 36.3 (d, 1C,
JPC = 49.5 Hz, H CC), 21.4 (s, 1C, C CH ), 19.2 (s, 1C,
CorthoCH ), 16.6 (s, 1C, PCCH ). P{ H} NMR (CDCl , 162 MHz):
PC
meta
PC
Cambridge Crystallographic Data Centre, 12 Union Road,
Cambridge CB2 1EZ, UK; fax: +44 1223 336033.
4
1
PC
para
PC
3
3
4
PC
meta
PC
3
3
PC
1
3
meta
3
3
1
1
3
3
3
E
Organometallics XXXX, XXX, XXX−XXX