the application of this alternative method of data analysis,
a novel product, N-(2-methylvinyl)-2-phenylindole 5, was
identified.
Experimental
General procedures
The handling of all air sensitive reagents was performed in a
glove bag purged with argon. Reagents were purchased from
Aldrich and used as received unless otherwise stated. All solvents
were pre-dried and distilled under an atmosphere of argon.
Acetone and acetone-d6 were dried with CaSO4 and distilled
under argon prior to use. Methanol was dried over molecular
sieves (4 A) and distilled from CaH2. 1,1,2,2-Tetrachloro-
ethane (TCE) was dried with CaCl2 and distilled under
argon. Thf-d8 was distilled from Na–benzophenone imme-
diately prior to use. 1,2,3,4,5-Pentamethylcyclopentadiene
was purchased from Lancaster and used without further
purification. Ir(III) chloride hydrate and rhodium(III) chloride
hydrate were obtained from Precious Metals Online (PMO)
and were used without further purification. Sodium
Fig. 1 Graphical representation of well components and catalytic
conversions of 2 using direct UV analysis. Each well contains 10 mol%
[M]2, 20 mol% ligand and 20 mol% NaBF4, and the reaction was
performed at 50 1C for 18 h in acetone–MeOH (2.5 : 1) and was
analysed using a direct UV analysis.
tetrakis[(3,5-trifluoromethyl)phenyl]borate
(NaBArF24),10
diluted and analysed via UV spectroscopy. The UV absor-
bance data for each time point were normalised using an
isosbestic point in the data set and the internal standard series
included in column 12, Fig. 1, was utilised for calibration of
the UV absorbances.
[Ir(COD)Cl]2,11 [Ir(CO)2Cl]n,12 [Ir(COE)2Cl]2,11 [Rh(COD)Cl]2,13
[Rh(CO)2Cl]2,14 [Rh(COE)2Cl]2,11 [RhCpCl2]2,15 [RhCp*Cl2]2
and [IrCp*Cl2]2,15 bis(1-pyrazolyl)methane (bpm),16 bis(N-methyl-
imidazolyl)methane (bim),17 N,N-bis(p-tolyl)diazabutadiene
(ptolDAD),18
N,N-bis(p-tolyl)1,2-dimethyldiazabutadiene
(dmptolDAD),19,20 N,N-(bismesityl)1,2-dimethyldiazabuta-
diene (dmmesDAD),21 N,N-(bismesityl)diazabutadiene (mesDAD),
bis(2,4,6-trimethylphenylimino)acenapthene (mesBIAN),22,23
Synthesis of [RhClCO(MesBIAN)] (6)
[Rh(CO)2Cl]2 (27 mg, 0.07 mmol) and bis(2,4,6-trimethyl-
phenylimino)acenapthene (mesBIAN) (53 mg, 0.13 mmol)
were dissolved in dichloromethane (15 mL) to give a dark
green solution. The reaction mixture was stirred at rt, under an
atmosphere of nitrogen, for 10 min. The solvent volume was
reduced to approximately a third of the volume and hexane
(5 mL) was added. A dark green solid began to precipitate out.
The mixture was cooled in an ice-bath to give a dark green
solid and a light green filtrate. The solid was collected by
filtration, washed with hexane (2 ꢁ 1 mL) and dried in vacuo.
[RhCl(CO)(mesBIAN)] was obtained as a dark green powder
(50 mg, 70%), mp 246–252 1C (dec.); Anal (%) found: C,
63.06; H, 5.32; N, 4.28. C31H28N2OClRh ꢁ 0.5 H2O, requires
C, 62.68; H, 4.74; N, 4.79; vmax/cmꢂ1 (nujol): 1980s (Rh–CO);
1H NMR (d, 600 MHz, tetrahydrofuran-d8): 8.21 (1H, d,
2-(2-phenylethynyl)aniline 2,24 [Rh(bim)(CO)2]BPh4 1,4,25
26
[Ir(bpm)(CO)2]BPh4
(dmbpm)]BF4,
[Cp*IrCl(mesim-mim)]BF4 and [Cp*IrCl(mesBIAN)]BF4
and [Cp*IrCl(bpm)]BF4, [Cp*IrCl-
[Cp*IrCl(bim)]BF4,
[Cp*IrCl(bik)]BF4,
15
were prepared by literature methods.
1H NMR spectra were recorded on a Bruker DPX300,
DMX500 and 600 spectrometers. All spectra were recorded
1
at 323 K unless otherwise specified. H NMR chemical shifts
were referenced internally to residual solvent resonances. UV
spectra were recorded in Helma quartz 96-well plates using
Bio-Tek PowerWave XS plate reader and analysed using KC4
Microplate Data Analysis Software.
Screening of hydroamination in acetone–MeOH with NaBF4
as counterion
3
3
0
0
JH5-H4 = 8.2 Hz, 5-H), 8.17 (1H, d, JH5 -H4 = 8.2 Hz,
3
3
50-H), 7.53 (1H, dd, JH4 -H5 = 8.2 Hz, JH4 -H3 = 7.2 Hz,
40-H), 7.40 (1H, dd, 3JH4-H5 = 8.2 Hz, 3JH4-H3 = 7.2 Hz, 4-H),
0
0
0
0
Full experimental details describing the generation of the
library of rhodium and iridium complexes screened as
catalysts can be found in our previous report.9 The library
of complexes was generated in situ by reacting standard
solutions of 2 molar equivalents of ligand and 1 molar
equivalent of bimetallic metal precursor in acetone at rt,
along with 2 molar equivalents of NaBF4 which was added
as a MeOH standard solution. Fig. 1 illustrates the compo-
nents in each well of the 96-well plate. An acetone solution of
substrate 2 was then immediately added to each of the wells
and an aliquot was taken from each well for analysis. The
reaction block was sealed and heated at 50 1C for 18 hours,
after which time an aliquot was again taken from each well,
3
7.14 (2H, s, 10-H), 7.04 (2H, s, 100-H), 6.80 (1H, d, JH3 -H4
0
0
=
7.2 Hz, 30-H), 6.65 (1H, d, 3JH3-H4 = 7.2 Hz, 3-H), 2.43 (3H, s,
p-CH3), 2.404 (3H, s, p0-CH3), 2.399 (6H, s, o-CH3), 2.32 (6H,
s, o0-CH3) ppm; 13C NMR (d, 125 MHz, tetrahydrofuran-d8):
188.3 (d, 1JRh-CO = 79.8 Hz, Rh-CO), 175.0 (C10), 166.9 (C1),
148.7 (C8), 145.0 (C7), 144.4 (C80), 138.5 (C11), 137.6 (C110),
133.7 (C6), 132.7 (C50), 131.3 (C4), 130.9 (C10), 130.6 (C40),
130.5 (C90), 130.4 (C100), 130.3 (C2), 130.0 (C5), 129.6 (C9),
128.1 (C20), 125.5 (C30), 122.8 (C3), 21.9 (p0-CH3), 21.7
(p-CH3), 19.2 (o0-CH3), 18.3 (o-CH3) ppm; m/z: (ES+) 605
(M + Na, 32%), 519 (100).
ꢀc
This journal is The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2009
New J. Chem., 2009, 33, 818–824 | 819