6
48
RULEV et al.
on a Bruker DPX-400 instrument (400 and 100 MHz,
(III), bp 43 44 C (1 mm). IR spectrum, , cm 1:
1
respectively) from solutions in CDCl at room tem-
1585 (C C), 1698 (C O). H NMR spectrum,
,
3
perature. The 13C signals were assigned using the
DEPT sequence. GC MS data were acquired on
a Hewlett Packard HP 5971A mass selective-detector
coupled with an HP-5890 chromatograph (energy
of ionizing electrons 70 eV; Ultra-2 column, 5% of
phenylmethylsilicone).
ppm (J, Hz): 1.45 1.70 m (6H, , -CH , piperidine),
2
2.30 s (3H, CH CO), 2.70 2.75 m (4H, -CH2,
3
piperidine), 4.47 d (1H, CH , J = 0.9), 4.87 d (1H,
2
1
3
CH , J = 0.9). C NMR spectrum, C, ppm: 24.16,
2
25.68 ( , -CH , piperidine); 27.69 (CH ), 50.66
2
3
(NCH ); 98.52 ( CH ); 157.34 ( C N); 200.54
2
2
+
(
1
C O). Mass spectrum, m/z (I , %): 153 (41, M ),
-
Bromocinnamaldehyde (IV) was prepared by
rel
52 (34), 110 (100), 54 (44), 43 (42). Found, %:
successive bromination and dehydrobromination of
cinnamaldehyde [12]. 3-Bromo-3-buten-2-one (I)
was synthesized by a procedure analogous to that
reported in [13].
C 70.00; H 10.00; N 8.87. C H NO. Calculated, %:
9
15
C 70.55; H 9.87; N 9.14.
3,4-Dipiperidinobutan-2-one (II) was identified
1
13
by the H and C NMR spectra, as well as by the
3
-Bromo-3-buten-2-one (I). A solution of 16 g
GC MS data [in a mixture with 3-piperidino-3-buten-
(
10 mmol) of bromine in 15 ml of CHCl was added
3
1
2
-one (III)]. H NMR spectrum, , ppm (J, Hz): 1.30
over a period of 0.5 h at 0 C to a solution of 7.0 g
10 mmol) of methyl vinyl ketone in 20 ml of CHCl3.
1
.55 m (12H, , -CH , piperidine), 2.14 s (3H,
(
2
CH CO), 2.30 2.50 m (10H, NCH ), 3.08 d.d (1H,
When the addition of bromine was complete, the
mixture was allowed to warm up to room temperature
and was left to stand for 3 h. The solution was
evaporated, the residue was dissolved in 20 ml of
diethyl ether, the solution was cooled to 10 C, a solu-
tion of 12.1 g (10 mmol) of N,N -dimethylaniline in
3
2
1
3
CHN, J = 9.1, 5.1). C NMR spectrum, C, ppm:
2
2
4.46, 24.61, 26.20, 26.52 ( , -CH , piperidine);
2
8.27 (CH ); 52.01, 55.27 (NCH ); 210.22 (C O).
3
2
+
Mass spectrum, m/z (I , %): 238 (< 1, M ), 195 (1),
rel
98 (100), 41 (13).
2
0 ml of Et O was added, and the mixture was left to
(Z,E)-2-[Methyl(phenyl)amino]-3-phenylpro-
2
stand for 12 h at room temperature. The mixture was
treated with water and extracted with ether (2 50 ml),
the extracts were dried over MgSO , the solvent was
distilled off, and the residue was distilled under
reduced pressure. Yield 6.0 g (40%), bp 55 56 C
penal (V). a. A mixture of 1.1 g (10 mmol) of
N-methylaniline, 1.1 g (5 mmol) of -bromocinnam-
aldehyde (IV), and 0.6 g (5.5 mmol) of triethylamine
in 2 ml of anhydrous THF was heated for 30 min at
90 C in a sealed ampule. The precipitate of triethyl-
amine hydrobromide was filtered off, and the filtrate
was evaporated. The residue was subjected to column
chromatography on silica gel using hexane ether (1:1)
as eluent to isolate 0.6 g (51%) of (E,Z)-2-[methyl-
(phenyl)amino]-3-phenylpropenal (V) as a colorless
oil. Both isomers were isolated by column chromatog-
4
1
(
(
(
20 mm) (cf. [14]). IR spectrum, , cm : 1609
C C), 1697 (C O). H NMR spectrum, , ppm
J, Hz): 2.43 s (3H); 6.38 d (1H, J = 2.4), 6.76 d (2H,
1
1
3
J = 2.4). C NMR spectrum, C, ppm: 26.03 (CH3),
29.53 ( CH ), 131.96 ( CBr), 191.88 (C O). Mass
1
2
+
spectrum, m/z (I , %): 150, 148 (45, M ); 107, 105
rel
1
raphy. IR spectrum, , cm : 1592 (C C), 1684
(
27); 143 (100). Found, %: C 32.11; H 3.68; Br 53.66.
1
(
(
C O). H NMR spectrum, , ppm: Z isomer: 3.03 s
C H BrO. Calculated, %: C 32.25; H 3.38; Br 53.63.
4
5
3H, NMe); 7.28 s (1H, CH ); 6.65 7.55 m (10H,
Reaction of 3-bromo-3-buten-2-one (I) with
C H ); 9.50 s (1H, CHO); E isomer: 3.24 s (3H,
piperidine. A solution of 2.8 g (18 mmol) of
-bromo-3-buten-2-one in 30 ml of anhydrous THF
was added with stirring to a solution of 3.4 g
40 mmol) of piperidine in 40 ml of anhydrous THF.
6
5
NMe); 6.90 7.50 m (11H, CH , C H ); 9.81 s (1H,
3
6
5
CHO). 13C NMR spectrum, , ppm: Z isomer: 37.81
NMe); 113.78, 118.87, 129.05, 129.47, 130.28,
(
1
(
1
1
(
(
39.77, 133.40, 146.79 (C H ); 142.36 (CH ); 143.54
The mixture was kept for 24 h at room temperature,
the precipitate of piperidine hydrobromide was filtered
off, and the filtrate was evaporated. A solution of
sodium methoxide in methanol (prepared from 0.2 g
of sodium and 20 ml of methanol) was added to the
residue, and the mixture was left to stand for 24 h
at room temperature. The mixture was treated with
water (10 ml) and extracted with ether (5 50 ml),
6 5
C N); 192.39 (CHO); E isomer: 40.52 (NMe);
19.00, 121.23, 128.33, 128.49, 128.78, 129.66,
34.18, 148.42 (C H ); 135.41 (CH ); 146.10
6
5
C N); 189.57 (CHO). Mass spectrum, m/z (I , %):
rel
+
2
37 (37, M ), 208 (56), 193 (100), 165 (44), 77 (60).
Found, %: C 80.27; H 6.56; N 5.86. C H NO.
16 15
Calculated, %: C 80.98; H 6.37; N 5.90.
the extracts were dried over MgSO and evaporated,
and the residue was distilled under reduced pressure
to obtain 0.6 g (22%) of 3-piperidino-3-buten-2-one
b. The reaction mixture (prepared as described
above in a) was kept for 15 min in a sealed ampule
placed in a microwave oven at a power of 700 W.
4
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 39 No. 5 2003