J.E. Nycz et al. / Journal of Molecular Structure 1002 (2011) 10–18
11
carried out on Silica Gel 60 (0.15–0.3 mm) Machery Nagel. Melting
points were determined on MPA100 OptiMelt melting point appara-
tus and uncorrected. Compounds 2a, 2b, 2c, 2d and 2e were pur-
chased from LGC Standards.
3-CH3Ar), 2.32 (s, 3H, 4-CH3Ar), 2.84 (s, 3H, NCH3), 4.95 (q,
JHH = 7.3 Hz, 1H, CH3CH), 7.24 (d, JHH = 8.2 Hz, 1H, aromatic), 7.67
(dd, JHH = 7.9 Hz, JHH = 1.4 Hz, 1H, aromatic), 7.72 (s, 1H, aromatic),
9.92 (bs, 1H, NH2); 13C{1H} NMR (CDCl3) d = 16.48, 19.77, 20.21,
31.64, 59.25, 126.54, 129.88, 130.32, 130.78, 137.71, 144.74,
2.1.1. Synthesis of 1a, 1b, 1c, 1d and 1e
194.43; IR (KBr): 3363 (
1688 ( C@O), 1675 (scissor. NH2), 1605, 1572 (
PhH), 1399, 1250 ( C-N), 763, 730 (wag. NH2); UV–Vis (metha-
nol; [nm]) (log ): 262.0 (5.32), 210.0 (5.33); X-ray CCDC 822797.
2-Methylamino-1-(4-methylphenyl)propan-1-one (1d) (yel-
lowish liquid) 1H NMR (CDCl3) d = 1.23 (d, JHH = 7.1 Hz, 3H, CHCH3),
2.26 (bs, 1H, NH), 2.30 (s, 3H, 4-CH3Ar), 2.34 (s, 3H, NCH3), 4.14 (q,
JHH = 7.0 Hz, 1H, CH), 7.21 (d, JHH = 8.1 Hz, 2H, aromatic), 7.80 (d,
JHH = 8.2 Hz, 2H, aromatic); 13C{1H} NMR (CDCl3) d = 19.64, 21.55,
34.47, 59.21, 128.25, 129.35, 133.01, 144.17, 202.68.
1-(4-Methylphenyl)-N-methyl-1-oxopropan-2-aminium chlori-
dum (2d) (colorless solid) m.p. = 230–231 °C (methanol); 1H NMR
(CDCl3) d = 1.79 (d, JHH = 7.1 Hz, 3H, CHCH3), 2.43 (s, 3H, CH3),
2.85 (bs, 3H, NCH3), 4.94 (bs, 1H, CHCH3), 7.30 (d, JHH = 8.0 Hz,
2H, aromatic), 7.84 (d, JHH = 8.1 Hz, 2H, aromatic), 9.32 (m, 1H,
NH2), 10.51 (m, 1H, NH2); 13C{1H} NMR (CDCl3) d = 16.49, 21.78,
31.72, 59.33, 129.00, 129.90, 130.58, 146.05, 194.25; IR (KBr):
m
NH), 2907 (
m
PhH), 2806, 2735 (
mCH3),
The water solution of 2a, 2b, 2c, 2d or 2e was alkalified by
K2CO3. Reagents were shaken for a few minutes. The mixture
was poured into CH2Cl2. The organic phase was separated and
dried by MgSO4. After the solvent was evaporated, the residue
was purified by chromatography.
m
mC@C), 1464
(m
m
e
2.1.2. Crystallization of 2a, 2b, 2c, 2d and 2e
The colorless crystals suitable for X-ray analysis were obtained
by slowly solvents’ evaporating at room temperature for 2a and 2b,
and in ꢀ35 °C for 2c and 2d. Crystallization of 2e is in progress.
2-(Ethylamino)-1-(4-methylphenyl)propan-1-one (1a) (yellow-
ish liquid) 1H NMR (CDCl3) d = 1.10 (t, JHH = 7.1 Hz, 3H, CH2CH3),
1.29 (d, JHH = 7.0 Hz, 3H, CHCH3), 2.22 (m, 1H, NH), 2.41 (s, 3H,
4-CH3Ar), 2.56 (ABX3, JHHgem = 12.8 Hz, JHH = 7.1 Hz, 2H, CH2CH3),
4.29 (q, JHH = 7.0 Hz, 1H, CHCH3), 7.27 (d, JHH = 8.2 Hz, 2H, aro-
matic), 7.86 (d, JHH = 8.2 Hz, 2H, aromatic); 13C{1H} NMR (CDCl3)
d = 15.44, 20.07, 21.63, 42.35, 57.51, 128.33, 129.42, 133.10,
144.21, 203.22.
N-Ethyl-1-(4-methylphenyl)-1-oxopropan-2-aminium chlori-
dum (2a) (colorless solid) m.p. = 198–199 °C (methanol); 1H NMR
(CDCl3) d = 1.53 (t, JHH = 7.3 Hz, 3H, CH2CH3), 1.81 (d, JHH = 7.2 Hz,
3H, CHCH3), 2.43 (s, 3H, 4-CH3Ar), 3.06–3.27 (m, 2H, CH2CH3),
4.96–5.06 (m, 1H, CHCH3), 7.31 (d, JHH = 8.0 Hz, 2H, aromatic),
7.86 (d, JHH = 8.2 Hz, 2H, aromatic), 9.02 (m, 1H, NH2), 10.69 (m,
1H, NH2); 13C{1H} NMR (CDCl3) d = 11.79, 16.86, 21.80, 42.12,
57.83, 128.96, 129.89, 130.44, 146.05, 194.25; IR (KBr): 3438
3356 (
C@O), 1606 (scissor. NH2), 1572 (
1248 ( C-N), 756, 734 (wag. NH2); UV–Vis (methanol; [nm])
(log ): 259.0 (5.20), 211.0 (5.02); X-ray CCDC 822035.
m
NH), 2964, 2910 (
mPhH), 2803, 2741, 2722 (
mCH3), 1687
(m
m
C@C), 1456 (
mPhH), 1358,
m
e
2-(Methylamino)-1-phenylbutan-1-one (1e) (yellowish liquid)
1H NMR (CDCl3) d = 0.84 (dt, JHH = 7.4 Hz, JHH = 1.3 Hz, 3H, CH2CH3),
1.49 (ABMX3, dqd, JHH = 14.1 Hz, JHH = 7.4 Hz, JHH = 5.2 Hz, 1H,
CH2CH3), 1.73 (ABMX3, dqd, JHH = 14.1 Hz, JHH = 7.4 Hz, JHH = 5.2 Hz,
1H, CH2CH3), 2.07 (bs, 1H, NH), 2.29 (s, 3H, NHCH3), 4.01 (dd,
JHH = 6.5 Hz, JHH = 5.3 Hz, 1H, CHCH2), 7.40 (bt, JHH = 7.5 Hz, 2H,
aromatic), 7.49 (tt, JHH = 7.4 Hz, JHH = 1.3 Hz, 1H, aromatic), 7.89
(dd, JHH = 8.3 Hz, JHH = 1.2 Hz, 2H, aromatic); 13C{1H} NMR (CDCl3)
d = 9.76, 26.39, 34.79, 65.07, 127.92, 128.52, 133.01, 136.19,
203.02.
(
m
NH), 2946 (
m
PhH), 2819, 2765 (
m
CH3), 1651 (
C-N), 768, 743
): 259.0 (5.17), 211.0
mC = O, scissor.
NH2), 1602 ( C@C), 1459 (
(wag. NH2); UV–Vis (methanol; [nm]) (log
m
mPhH), 1340, 1263 (m
e
(5.01); X-ray CCDC 823158.
1-(1,3-Benzodioxol-5-yl)-2-(methylamino)propan-1-one (1b)
(yellowish liquid). 1H NMR (CDCl3) d = 1.21 (d, JHH = 7.0 Hz, 3H,
CHCH3), 2.27 (bs, 3H, NCH3), 4.05 (q, JHH = 7.0 Hz, 1H, CHCH3),
5.97 (s, 2H, OCH2), 6.79 (d, JHH = 8.2 Hz, 1H, aromatic), 7.38 (s,
1H, aromatic), 7.51 (d, JHH = 8.2 Hz, 1H, aromatic); 13C{1H} NMR
(CDCl3) d = 19.79, 34.50, 59.15, 101.78, 107.90, 107.92, 124.32,
130.36, 148.22, 151.88, 201.24.
1-(1,3-Benzodioxol-5-yl)-N-methyl-1-oxopropan-2-aminium
chloridum (2b) (colorless solid) m.p. = 225–226 °C (methanol); 1H
NMR (CDCl3) d = 1.80 (d, JHH = 7.2 Hz, 3H, CHCH3), 2.80 (bs, 3H,
NCH3), 4.76 (bs, 1H, CHCH3), 6.11 (s, 2H, OCH2), 6.92 (d,
JHH = 8.3 Hz, 1H, aromatic), 7.42 (s, 1H, aromatic), 7.53 (d,
JHH = 8.8 Hz, 1H, aromatic); 13C{1H} NMR (DMSO-d6) d = 25.26,
40.13, 67.44, 111.99, 117.42, 118.04, 135.32, 136.97, 157.71,
N-Methyl-1-oxo-1-phenylbutan-2-aminium chloridum (2e)
(colorless solid) m.p. = 190–191 °C (methanol); 1H NMR (CDCl3)
d = 1.02 (t, JHH = 7.6 Hz, 3H, CH2CH3), 2.18 (dqd, JHH = 15.0 Hz,
JHH = 7.5 Hz, JHH = 5.1 Hz, 1H, CH2CH3), 2.39 (ABMX3, dqd,
JHH = 15.0 Hz, JHH = 7.5 Hz, JHH = 5.1 Hz, 1H, CH2CH3), 2.85 (s, 3H,
NH2CH3), 5.04 (t, JHH = 5.2 Hz, 1H, CHCH2), 7.52 (t, JHH = 7.7 Hz,
2H, aromatic), 7.65 (t, JHH = 7.4 Hz, 1H, aromatic), 7.98 (d,
JHH = 7.3 Hz, 2H, aromatic), 9.91 (m, 2H, NH2CH3); 13C{1H} NMR
(CDCl3) d = 8.98, 23.71, 32.21, 63.98, 128.77, 129.19, 134.14,
134.70, 194.60.
2.2. DFT calculations
The calculations were carried out by using Gaussian09 [10] pro-
gram. The DFT/B3LYP [11,12] method was used for the geometry
optimization and electronic structure determination. The geometry
optimizations were made for gas phase molecules. The calculations
were performed using the polarization functions for all atoms: 6-
31Gꢁꢁ – carbon, nitrogen, oxygen and hydrogen. The contribution
of a group to a molecular orbital was calculated using Mulliken
population analysis. GaussSum 2.2 [13] was used to calculate
group contributions (aromatic, N-aliphatic, CH3CHC(@O) frag-
ments) to the molecular orbitals and to prepare the density of
states (DOS). The DOS spectra were created by convoluting the
molecular orbital information with Gaussian curves of unit height
and Full Width at Half Maximum (FWHM) of 0.3 eV. The electro-
static potential (ESP) surfaces were plotted by using gOpenMol
v2.31 program. The electronic spectra were calculated by the
time-dependent density functional (TDDFT) [14] method based
on the optimized geometries in the singlet states.
162.18, 203.81; IR (KBr): 3435 (
m
NH), 2920 (
C@O + scissor. NH2), 1603 (
PhH), 1349, 1299 ( C-N), 1261, 1090 ( C-O), 767, 741 (wag.
): 307.8 (4.97), 270.2 (4.88),
m
PhH), 2799, 2735
(m
CH3), 1679 (
m
mC@C), 1502, 1452
(m
m
m
NH2); UV–Vis (methanol; [nm]) (log
e
224.8 (5.19), 192.6 (5.41); X-ray CCDC 819333.
1-(3,4-Dimethylphenyl)-2-(methylamino)propan-1-one
(1c)
(yellowish liquid) 1H NMR (CDCl3) d = 1.19 (d, JHH = 7.1 Hz, 3H,
CH3CH), 1.93 (s, 1H, NH), 2.21 (s, 3H, 3-CH3Ar), 2.22 (s, 3H, 4-
CH3Ar), 2.26 (s, 3H, NCH3), 4.10 (q, JHH = 7.0 Hz, 1H, CH3CH), 7.12
(d, JHH = 7.9 Hz, 1H, aromatic), 7.61 (dd, JHH = 7.9 Hz, JHH = 1.6 Hz,
1H, aromatic), 7.66 (s, 1H, aromatic); 13C{1H} NMR (CDCl3)
d = 19.47, 19.58, 19.70, 34.40, 59.05, 125.65, 129.03, 129.65,
133.40, 136.82, 142.58, 202.85.
1-(3,4-Dimethylphenyl)-N-methyl-1-oxopropan-2-aminium
chloridum (2c) (colorless solid) m.p. = 211–212 °C (methanol); 1H
NMR (CDCl3) d = 1.78 (d, JHH = 7.2 Hz, 3H, CH3CH), 2.30 (s, 3H,