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zine), 7.05–7.09 (d, 3H, ArH para, ortho, meta to CF3),
7.27–7.41 (m, 1H, ArH ortho to CF3), 7.44–7.58 (m, 3H,
ArH meta, para to CO), 7.90–7.99 (m, 2H, ArH ortho to
CO).
4.3.4. ( )-1-Phenyl-3-[4-(3-trifluoromethyl-phenyl)-pip-
erazin-1-yl]-propan-1-ol hydrochloride salt (9). Spectral
data: IR (cmÀ1): 3318, 3024, 2929, 2557, 1610, 1351,
1251, 1166, 1125, 944. Mass (m/e): 365, 243, 188, 144,
107. 1H NMR (d ppm): 2.28–2.31 (m, 2H, CH2CHOH),
3.17–3.32 (m, 4H, N–CH2 piperazine), 3.48–3.96 (m,
6H, N–CH2 piperazine), 7.14–7.24 (m, 3H, ArH para,
ortho, meta to CF3), 7.29–7.42 (m, 6H, ArH ortho to
CF3 Ph).
4.2.5. 1-Phenyl-3-(4-pyridin-2-yl-piperazin-1-yl)-propan-
1-one hydrochloride salt (5). Spectral data: IR (cmÀ1):
3076, 2962, 1684, 1602, 1280, 1184, 974. Mass (m/e):
1
296 (M++1), 176, 121, 107. H NMR (d ppm): 3.75–
3.82 (m, 8H, CH2CO, N–CH2 piperazine), 4.09–4.13
(m, 4H, N–CH2 piperazine), 7.23–7.26 (t, 1H, ArH meta
to N), 7.44–7.49 (d, 1H, ArH para to N), 7.62–7.70 (m,
2H, ArH ortho to CO), 7.77–7.81 (m, 1H, ArH meta to
N), 8.09–8.13 (m, 3H, ArH meta, para to CO), 8.18–8.22
(m, 1H, ArH ortho to N).
4.3.5. ( )-1-Phenyl-3-(4-pyridin-2-yl-piperazin-1-yl)-pro-
pan-1-ol hydrochloride salt (10). Spectral data: IR
(cmÀ1): 3575, 3024, 2938, 1596, 1126, 942. Mass (m/e):
297, 202, 189, 175, 121, 107, 92, 71. 1H NMR (d
ppm): 1.88–1.96 (m, 2H, CH2CHOH), 2.58–2.77 (m,
6H, N–CH2 piperazine), 3.58–3.63 (t, 4H, N–CH2 piper-
azine), 4.94–5.00 (t, 1H, CHOH), 6.61–6.67 (d, 2H, ArH
meta to N), 7.28–7.35 (m, 1H, ArH para to N), 7.38–
7.53 (m, 5H, ArH of Ph), 8.18–8.20 (d, 1H, ArH ortho
to N).
4.2.6. 1-Phenyl-3-(4-pyrimidin-2-yl-piperazin-1-yl)-pro-
pan-1-one hydrochloride salt (6). Spectral data: IR
(cmÀ1): 3024, 2928, 1678, 1148, 980. Mass (m/e): 297,
279, 202, 189, 149, 122, 106, 91, 77. 1H NMR (d
ppm): 2.55–2.60 (t, 4H, N–CH2 piperazine), 2.84–2.92
(t, 2H, CH2CO), 3.19–3.26 (t, 2H, N–CH2, piperazine),
3.81–3.86 (t, 4H, N–CH2 piperazine), 6.45–6.49 (t, 1H,
ArH meta to N), 7.43–7.60 (m, 3H, ArH para, meta to
CO), 7.95–7.99 (d, 2H, ArH ortho to CO), 8.28–8.31
(d, 2H, ArH ortho to N).
4.3.6. ( )-1-Phenyl-3-(4-pyrimidin-2-yl-piperazin-1-yl)-
propan-1-olhydrochloride salt (11). Spectral data: IR
(cmÀ1): 3214, 3024, 2895, 1582, 1130, 975. Mass (m/e):
1
299, 203, 177, 148, 122, 108. H NMR (d ppm): 1.87–
1.96 (m, 2H, CH2CHOH), 2.49–2.81 (m, 6H, N–CH2
piperazine), 3.86–3.91 (t, 4H, N–CH2 piperazine),
4.94–5.00 (t, 1H, CHOH), 6.47–6.52 (t, 1H, ArH meta
to N), 7.35–7.41 (m, 5H, ArH of Ph), 8.30–8.32 (d,
2H, ArH ortho to N).
4.3. Synthesis of ( )-3-(4-(substituted)-piperazin-1-yl)-1-
phenyl-propan-1-ol hydrochloride salt (7–11)
4.3.1. General procedure. The 3-(4-(substituted)-pipera-
zin-1-yl)-1-phenyl-propan-1-one free base (0.01 mol)
was taken into methanol and cooled in icebath
(0–5 ꢁC) and NaBH4 (0.015 mol) was added in small por-
tions with stirring. After completion (as monitored by
TLC), the methanol was distilled off and the residue was
taken into water and extracted with ethyl acetate. The
combined organic layer was washed with water and dried
over Na2SO4. The Na2SO4 was filtered off and washed
with ethyl acetate and the solvent is evaporated on rotava-
por. The formed oily residue was taken into methanol and
cooled in icebath (0–5 ꢁC) and concd HCl (2 equiv) was
added dropwise and kept stirring in icebath for 3 h. Later
the methanol was distilled off and the residue was taken
into hexane. A white solid separated out which was fil-
tered, washed with hexane, and dried.
4.4. Synthesis of ( )-1-(substituted)-4-[3-phenyl-3-(4-tri-
fluoromethyl-phenoxy)-propyl]-piperazine hydrochloride
salt (12–16)
4.4.1. General procedure. To a precooled mixture of
NaH (0.02 mol) and DMAC (5 ml), 3-(4-(substituted)-
piperazin-1-yl)-1-phenyl-propan-1-ol
(0.01 mol)
in
DMAC (5 ml) was added and the reaction mixture
was brought to room temperature and then heated in
oilbath to 90 ꢁC for 2 h. The reaction mixture was
cooled to room temperature and 4-chlorobenzotrifluo-
ride (0.02 mol) was added dropwise and the reaction
mixture was again heated to 110 ꢁC until the reaction
was complete (as monitored by TLC). The reaction mix-
ture was then diluted with water and extracted with eth-
yl acetate. The organic layer was washed and dried over
Na2SO4. The Na2SO4 was filtered off and washed with
ethyl acetate and the solvent was evaporated on rotava-
por. The formed oily residue was taken into methanol
and cooled in icebath (0–5 ꢁC) and concd HCl (2 equiv)
was added dropwise and kept stirring in icebath for 3 h.
Later the methanol was distilled off and the residue was
taken into ethyl acetate/hexane (1:1) mixture. A white
solid separated out which was filtered, washed with ethyl
acetate/hexane (1:1), and dried.
4.3.2. ( )-3-(4-Methyl-piperazin-1-yl)-1-phenyl-propan-1-
ol hydrochloride salt (7). Spectral data: IR (cmÀ1): 3360,
3018, 2914, 2426, 1218, 1036, 758. Mass (m/e): 234,127,
1
113, 107, 83, 70. H NMR (d ppm): 1.74–1.89 (m, 2H,
CH2CHOH), 2.28 (s, 3H, N–CH3), 2.51–2.76 (m, 10H,
N–CH2 piperazine), 4.90–4.95 (t, 1H, CHOH), 7.33–
7.36 (m, 5H, ArH).
4.3.3. ( )-3-[4-(3-Chloro-phenyl)-piperazin-1-yl]-1-phen-
yl-propan-1-ol hydrochloride salt (8). Spectral data: IR
(cmÀ1): 3408, 3120, 2922, 2550, 1244, 1084, 898. Mass
4.4.2. ( )-1-Methyl-4-[3-phenyl-3-(4-trifluoromethyl-
phenoxy)-propyl]-piperazine hydrochloride salt (12).
1
(m/e): 330, 209, 111, 83, 70. H NMR (d ppm): 2.25–
2.31 (m, 2H, CH2CHOH), 3.00 (m, 4H, N–CH2 pipera-
zine), 3.26–3.34 (t, 2H, N–CH2 ), 3.64 (m, 4H, N–CH2
piperazine), 4.79–4.89 (t, 1H, CHOH), 6.79–6.90 (m,
3H, ArH meta to Cl), 7.16–7.50 (m, 6H, ArH).
Spectral data: IR (cmÀ1): 3014, 2930, 1326, 1217, 1164,
1013, 764. Mass (m/e): 379, 251, 235, 127, 113, 105. H
1
NMR (d ppm): 1.81–1.90 (m, 2H, CH2CHOR), 2.28–
2.30 (s, 3H, N–CH3), 2.45–2.60 (m, 10H, N–CH2 piper-