S. Bhaduri, G. K. Lahiri et al.
FULL PAPER
romethane (35 mL) and distilled triethylamine (5 mg) was added
under nitrogen. A solution of 2-(diphenylphosphanyl)ethylamine
(4.367 mmol, 1 g) in dry dichloromethane (10 mL) was added drop
wise to the solution of chlorodiphenylphosphane at 0 °C over
20 min under nitrogen. The stirring was allowed to continue for
another 10 min at 0 °C. The solution was then allowed to stir for
next 16 h at room temp., and crystalline triethylammoniumhydro-
chloride precipitated out. The solution was filtered and the filtrate
was evaporated to dryness. The gummy solid obtained was dis-
solved in minimum volume of distilled hot ethanol and allowed to
cool inside a refrigerator overnight. The crystalline mass was col-
lected by filtration and dried under vacuum (Yield: 5.3 g, 80%).
The ligand was characterized by single-crystal X-ray diffraction
(Figure 1) and 1H (Figure S1a) and 31P NMR spectroscopy (Figure
S2a). C38H34NP3 (597.1904): calcd. C 76.36, H 5.74, N 2.34; found
ization and absorption effects, and the non-hydrogen atoms were
refined anisotropically. Hydrogen atoms were included in the re-
finement process as per the riding model. The crystal of 2 contains
one normal CH3CN molecule and one disordered CH3CN mole-
cule as solvent of crystallization. Important crystallographic details
and selected bond lengths and angles are listed in Tables S1 and
Table S2, respectively.
CCDC-773831 (for L) and -773832 (for 2) contain the supplemen-
tary crystallographic data for this paper. These data can be ob-
tained free of charge from The Cambridge Crystallographic Data
Centre via www.ccdc.cam.ac.uk/data_request/cif.
Supporting Information (see footnote on the first page of this arti-
cle): X-ray parameters, product distribution in different palladium-
catalyzed reactions, characterization of ligand L, catalyst 1, inter-
mediates, different substituted phenols, and substituted biphenyls.
1
C 76.21, H 5.70, N 2.21. H NMR (CDCl3, 300 MHz): δ = 7.10–
7.36 (m, 30 H, Ph–H), 3.37–3.42 (sx, 2 H, H2C–PPh2), 1.55 [t, 2
H, H2C–N(PPh2)2] ppm. 31P NMR (CDCl3, 300 MHz, δ [ppm]):
–21.802 [s, 1P, H2C–P(3)Ph2], 60.605 [s, 2P, H2C–N{P(1,2)Ph2}2]
Acknowledgments
ppm. IR (KBr): ν = 2924, 2853, 3068, 3049, 1584, 1478, 1433, 1091,
˜
1054, 842, 740 cm–1.
The financial support received from Department of Science and
Technology (DST), New Delhi and Council of Scientific and Indus-
trial Research (CSIR) (fellowship to A. D. C.) New Delhi is grate-
fully acknowledged. X-ray and NMR studies were carried out at
the National Single-Crystal X-ray Diffraction Facility and Sophis-
ticated Analytical Instrumentation Facilities (SAIF), IIT Bombay,
respectively.
Synthesis of 1: To a solution of L (50 mg, 0.084 mmol) in dichloro-
methane (10 mL) in a two-necked round-bottomed flask was added
dropwise Pd(COD)Cl2 (22 mg, 0.078 mmol) in dichloromethane
(5 mL) over 10 min under nitrogen. The transparent yellow solu-
tion was stirred for 6 h. The solution was then concentrated (ca.
2–3 mL) under reduced pressure and diethyl ether was added to
precipitate the yellow complex. It was allowed to stand overnight
inside the refrigerator for complete precipitation. The product was
collected by filtration, washed with diethyl ether and dried under
vacuum. C38H34Cl2NP3Pd (773.0316): calcd. C 58.99, H 4.40, N
1.69; found C 58.76, H 4.43, N 1.71. 1H NMR [(CD3)2SO,
300 MHz]: δ = 6.9–7.9 (m, 30 H, Ph–H), 3.1–3.2 (sx, 2 H, H2C–
PPh2), 1.8 [t, 2 H, H2C–N(PPh2)2] ppm. 31P NMR [(CD3)2SO,
300 MHz (ppm)]: δ = 19.015 [s, 1 P, H2C–P(3)Ph2–Pd], 56.2 [d, 1 P,
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H C–NP(2)Ph ], 74.10 [dd, 1 P, Pd–P(1)Ph –N] ppm. IR (KBr): ν
˜
2
2
2
= 3053, 2921, 2854, 1629, 1434, 1183, 1099, 1077, 997, 825, 744,
714, 690, 513 cm–1.
Catalytic Experiments: Catalyst 1 (5 mg, 0.0065 mmol) and aryl-
boronic acid (0.65 mmol) were dissolved in solvent (5 mL) along
with freshly distilled NEt3 (2 mg, 0.02 mmol). The resultant reac-
tion mixture was stirred for 24 h at 298 K either under bubbling of
O2 or air through the mixture. The progress of each reaction was
monitored by GC. In each case authenticated samples were used
to standardize the GC experiments. The solvent was removed under
reduced pressure after each reaction and the product was passed
through a silica gel (60–120 mesh) column using hexane/ethyl acet-
ate as the eluent. In case of more than one product, further separa-
tion was performed on a preparatory TLC plate using a hexane/
petroleum ether–ethyl acetate mixture. On removal of the solvent
under reduced pressure pure products were obtained in each case
and the isolated products were used to calculate the yield. The for-
mation of pure products were further confirmed by 1H NMR spec-
troscopy. All the reactions were carried out three times to establish
the reproducibility and reliability of the results.
Crystallographic Details: Single crystals of L (Figure 1) and 2 (Fig-
ure 2) were grown by slow evaporation of 1:1 acetonitrile/hexane
solutions of L and 1 at 298 K. Single-crystal X-ray diffraction data
were collected using an OXFORD XCALIBUR-S CCD single-
crystal X-ray diffractometer at 150 K. The structures were solved
and refined by full-matrix least-squares techniques on F2 using the
SHELX-97 program.[25] All data were corrected for Lorentz polar-
3238
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