J Chem Crystallogr (2012) 42:508–512
Experimental
509
152.9, 148.1, 136.1, 135.6, 130.5, 125.9, 125.0, 122.8,
121.5, 118.7, 116.0, 115.3, 36.8.
Materials
Method 2: Hydrobromide Salt [2]
Bromoacetyl bromide and 2-aminothiophenol were obtained
from Aldrich and used without purification. All solvents
were reagent grade and used as received.
Alternatively, the uncharacterized white solid (0.9914 g)
was dissolved in 5 mL of hot methanol. The clear yellow
solution was allowed to cool to room temperature. Small
white needles of [2] were filtered via gravity filtration,
washed with methanol and analyzed by NMR and X-ray
crystallography. 1H-NMR (d4-MeOD, 500 MHz, d (ppm)):
7.95 (d, J = 1.4 Hz, 1H), 7.93 (d, J = 1.6 Hz, 1H), 7.71
(dd, J = 1, 8.0 Hz, 1H), 7.52 (dt, J = 1, 7.9 Hz, 1H),
7.48–7.41 (overlapped m, 3H), 7.37 (dt, J = 2, 7.5 Hz,
1H), 3.34 (s, 2H). 13C-NMR (d4-MeOD, 500 MHz, d
(ppm)): 170.2, 153.2, 137.4, 136.7, 135.5, 131.9, 130.4,
128.9, 127.7, 127.0, 124.4, 123.4, 123.1. 13C-NMR
(d6-DMSO, 500 MHz, d (ppm)): 168.8, 152.3, 135.2, 134.8,
134.2, 131.1, 129.6, 126.2, 125.3, 122.4, 122.3, 35.7.
Physical Measurements
1H- and 13C-NMR spectra were obtained in d4-MeOD and
referenced to the MeOH solvent signal at 3.30 ppm using a
Bruker DRX 500 MHz Spectrometer. Electrospray ioni-
zation mass spectrometry (ESI–MS) was performed at the
University of Missouri using a Finnigan TSQ7000 triple-
quadrupole mass spectrometer in the positive ion mode.
2-[(2-Benzothiazolylmethyl)thio]-benzenamine
Bromoacetyl bromide (0.87 mL, 10 mmol) was added
to 20 mL of dichloromethane with stirring and cooled to
-78 °C. 2-Aminothiophenol (2.2 mL, 21 mmol) was
diluted with 20 mL of dichloromethane, and then added
dropwise to the bromoacetyl bromide solution. During
addition, a white precipitate formed immediately. The
reaction mixture was continuously stirred for 30 min at
-78 °C and then warmed overnight to room temperature.
The resultant mixture contained green-yellow solids, which
were filtered and washed with dichloromethane to yield a
white precipitate and an orange-brown filtrate. Yield:
2.3549 g (87%). ESI–MS (m/z): 272.88 (calc. 273.05
[M ? H]?).
X-ray Diffraction Analysis
The crystal of [1] was approximately 0.55 9 0.25 9
0.05 mm; [2] approximately 0.50 9 0.20 9 0.05 mm.
Intensity data were obtained on a Bruker APEXII using the
x-scan mode with Mo Ka radiation from a graphite
˚
monochromator (k = 0.71073 A). Important information
regarding the crystal data and structure refinement are lis-
ted in Table 1. Lattice constants for the crystal of [1] were
obtained from 2,968 centered reflections (1.76° B h
B 27.57°); [2] 3,698 centered reflections (2.26° B h
B 27.55°). The structures were solved by direct methods
and refined with full-matrix least-squares techniques,
employing the SHELX programs and X-Seed [8, 9]. All
non-hydrogen atoms were refined with anisotropic thermal
parameters. The hydrogen atoms were placed at calculated
positions and included in the refinement using a riding
model, with fixed isotropic U. The final least-squares cycle
for the crystal of [1] was calculated with 18 atoms and 165
parameters and afforded R = 0.0343, Rw = 0.0844. The
final least-squares cycle for the crystal of [2] was calcu-
lated with 21 atoms and 195 parameters and afforded
R = 0.0296, Rw = 0.0599. The polarity of the structure of
[2] was determined by refinement of the Flack parameter,
0.012 (5). Final difference maps of both structures had no
features of chemical significance.
Method 1: Free Base [1]
The uncharacterized white solid (0.2749 g) was added
to 10 mL of methanol and stirred to yield a clear, pale-
yellow solution. Nickel(II) acetate tetrahydrate (0.1521 g,
0.6112 mmol) dissolved in about 4 mL of deionized water
(clear, pale green solution) was added to the pale-yellow
solution, which became noticeably cloudy upon addition.
The mixture was allowed to stir for about 45 min at room
temperature, filtered, and the filtrate collected. The filtrate
was heated and mixture remained slightly cloudy. The
mixture was allowed to cool to room temperature, capped,
and placed in the freezer for 1 week. The light green
mother liquor was decanted and crystals of [1] were har-
vested from the sides of the vial and analyzed by X-ray
crystallography. 1H-NMR (CDCl3, 500 MHz, d (ppm)):
7.94 (d, J = 8.0 Hz, 1H), 7.80 (d, J = 7.5 Hz, 1H), 7.43
(t, J = 7.3 Hz, 1H), 7.4-7.29 (overlapped m, 2H), 7.12
(br s, 1H), 6.68 (br s, 1H), 6.59 (br s, 1H) 4.33 (s, 2H), 4.09
(br s, 2H). 13C-NMR (CDCl3, 500 MHz, d (ppm)): 168.8,
Results and Discussion
The previously reported 2-[(2-benzothiazolylmethyl)thio]-
benzenamine was inadvertently synthesized during a pro-
cedure to synthesize a new N2S2 ligand. The product was
123
Demoin, Dustin W.
