FULL PAPERS
Nicolas L. Rotta-Loria et al.
(606 mg, 1.8 mmol), amine (0.63 mmol), dihaloarene
(0.6 mmol), and toluene (0.6 mL) were added to a screw
capped vial containing a small magnetic stir bar. The vial
was sealed with a cap containing a PTFE septum, removed
from the glove-box, placed in a temperature-controlled alu-
minum heating block set at 908C, and vigorous magnetic
stirring was initiated. The reaction progress was monitored
qualitatively by use of GC methods. For example, in the
case of reactions involving n-octylamine, upon formation of
the independently prepared and characterized intermediate
N-(2-chlorophenyl)octylamine B (6 h), the vial was removed
from the heat, cooled to room temperature and returned to
the glove-box. The cap was removed and the corresponding
ketone (0.6–1.2 mmol as specified, except for 10 equivalents
in the case of acetone) was added to the reaction mixture.
The PTFE septum cap was then reaffixed to the vial, the
vial was removed from the glove-box and placed back on
the aluminum heating block set at 908C for 16 h. Subse-
quently, the vial was removed from the heating block and
left to cool to ambient temperature. The crude reaction mix-
ture was dissolved in ethyl acetate (10 mL) and poured onto
brine (10 mL). The layers were separated and the organic
layer was extracted with ethyl acetate (2ꢂ10 mL). The or-
ganic fractions were combined, dried over Na2SO4 and con-
centrated under reduced pressure. The crude residue was
purified by use of column chromatography over alumina or
preparative thin layer chromatography using a glass-backed
silica plate. Note that for reactions employing acetone, a re-
sealable glass reaction vessel equipped with a PTFE stopper
was employed.
Synthetic Procedure for N-(2-Chlorophenyl)octyl-
amine (B)
Pre-catalyst complex (Mor-DalPhos)Pd(h1-cinnamyl)Cl (A)
(17.7 mg, 0.024 mmol), Mor-DalPhos (5.6 mg, 0.012 mmol),
Cs2CO3 (606 mg, 1.8 mmol), octylamine (104.1 mL,
0.63 mmol), 1-chloro-2-iodobenzene (73.3 mL, 0.6 mmol),
and toluene (0.6 mL) were added to a screw capped vial
containing a small magnetic stir bar. The vial was sealed
with a cap containing a PTFE septum, removed from the
glove-box, placed in a temperature-controlled aluminum
heating block set at 908C, and vigorous magnetic stirring
was initiated. After 6 h the vial was removed from the heat-
ing block and left to cool to ambient temperature. The
crude reaction mixture was dissolved in ethyl acetate
(10 mL) and poured onto brine (10 mL). The layers were
separated and the organic layer was extracted with ethyl
acetate (2ꢂ10 mL). The organic fractions were combined,
dried over Na2SO4 and concentrated under reduced pres-
sure. The crude residue was purified by column chromatog-
raphy. The title product was isolated as a brown oil (yield:
96%) over alumina using 100% hexanes as the eluent
1
system. H NMR (500 MHz, CDCl3): d=7.30 (d, J=7.5 Hz,
1H), 7.19 (t, J=7.8 Hz, 1H), 6.72–6.65 (m, 2H), 4.32 (s,
1H), 3.23–3.19 (m, 2H), 1.75–1.70 (m, 2H), 1.50–1.36 (m,
10H), 0.96 (t, J=7.2 Hz, 3H); 13C{1H} NMR (125.8 MHz,
CDCl3): d=144.6, 129.4, 128.1, 119.3, 117.1, 111.4, 44.0, 32.2,
29.7 (two signals), 29.6, 27.5, 23.0, 14.4; HR-MS (ESI+):
m/z=240.1514 [M+H]+, calculated for C14H23ClN:
240.1519.
General Catalytic Procedure (GP2) for the
Formation of Indoles Using a “One-Pot, One-Step”
Protocol Under Non-Inert Atmosphere Conditions
Acknowledgements
We thank the Natural Sciences and Engineering Research
Council of Canada (Discovery and CHRP Grants to M.S.;
Postgraduate Scholarships to P.G.A. and C.B.L.), the Canadi-
an Institutes of Health Research (CHRP), the Nova Scotia
Health Research Foundation, and Dalhousie University for
their generous support of this work.
Unless specified otherwise in the text, pre-catalyst complex
(Mor-DalPhos)Pd(h1-cinnamyl)Cl
(A)
(17.7 mg,
0.024 mmol), Mor-DalPhos (5.6 mg, 0.012 mmol), Cs2CO3
(606 mg, 1.8 mmol), octylamine (0.63 mmol), 1-chloro-2-io-
dobenzene (73.3 uL, 0.6 mmol), ketone (1.2 mmol), and tol-
uene (0.6 mL) were all added to a screw capped vial con-
taining a small magnetic stir bar within the glove-box.
Please note that the use of the glove-box in this manner was
necessitated by the location of the high-precision analytical References
balance within the laboratory. The vial was sealed with
a cap containing a PTFE septum, removed from the glove-
box, opened to an atmosphere of air for a minimum of three
minutes and subsequently sealed under air. The vial was
then placed in a temperature-controlled aluminum heating
block set at 908C for 16 h. The vial was removed from the
heating block and left to cool to ambient temperature. The
crude reaction mixture was dissolved in ethyl acetate
(10 mL) and poured onto brine (10 mL). The layers were
separated and the organic layer was extracted with ethyl
acetate (2ꢂ10 mL). The organic fractions were combined,
dried over Na2SO4 and concentrated under reduced pres-
sure. The crude residue was purified by use of column chro-
matography over alumina or preparative thin layer chroma-
tography using a glass-backed silica plate. Note that for re-
actions employing acetone, a resealable glass reaction vessel
equipped with a PTFE stopper was employed.
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