SYNTHESIS, SPECTRALꢀLUMINESCENT PROPERTIES
1189
Zinc(II) complex with 3,3',5,5'ꢀtetraphenylꢀms
azaꢀ2,2'ꢀdipyrrolylmethene (6). A solution of 0.124 g
0.556 mmol) of Zn(AcO)2 2H O in 12 mL of
ꢀbutanol was added to a solution of 0.301 g (0.667 mmol)
of 3,3',5,5'ꢀtetraphenylꢀmsꢀazaꢀ2,2'ꢀdipyrrolylmethene
in 10 mL of 1ꢀbutanol and the mixture was heated at
reflux for 2 h. The solvent was completely removed
under reduced pressure, the residue was dissolved in
methylene chloride and chromatographed on silica gel
(L 100/250). The eluate was evaporated and the comꢀ
plex was precipitated with methanol on strong cooling.
Yield 0.243 g (0.243 mmol, 72.8%).
ꢀ
R
R
X
(
1
⋅
2
R
R
N
N
N
N
X
Zn(OAc)
2
⋅
2H
2
O
R
R
R
R
2
Zn
X
ROH
NH
N
R
R
R
R
R = Me, Х = СН (
R = Ph, Х = N (
4
); R = Ph, Х = СН (
); ROH – is the corresponding alcohol
5
);
6
.
Electronic absorption spectrum (
λ
max, nm (log )):
ε
Scheme 2.
650 (4.71), 590 (4.91), 480–495 (4.02), 306 (4.81)
(
CHCl ); 652 (4.74), 595 (4.91), 480–494 (3.81), 303
3
Zinc(II) complex with 3,3',5,5'ꢀtetramethylꢀ2,2'ꢀ
(
4.80) (DMF).
dipyrrolylmethene (4). 3,3',5,5'ꢀTetramethylꢀ2,2'ꢀ
dipyrrolylmethene hydrobromide (0.115 g, 0.407
mmol) was dissolved on heating and stirring in 5 mL of
methanol, 0.11 mL (0.814 mmol) of triethylamine and
1H NMR (500 MHz, CDCl ),
, ppm): 6.73 (s,
δ
3
4
2
H, CH ), 7.51–7.52 (d, 20H, H Ph), 7.87–7.89 (d,
pyr
0H, H Ph).
For C H N Zn anal. calcd. (%): C,79.87; H,
a solution of 0.178 g (0.814 mmol) of Zn(AcO)2
⋅
64 44
6
4
.61; N, 8.73.
2
H O in 3 mL of methanol was added. The solution
2
was heated at reflux for 1 h. The mixture was cooled,
the precipitate of complex was separated by filtration,
washed sequentially with hot water, methanol, and
ether and dried in air. Yield 0.090 g (0.194 mmol,
Found (%): C, 79.54; H, 4.27; N, 8.53.
The corresponding dipyrrolylmethenes for the synꢀ
thesis of the complexes were prepared by condensation
of appropriate pyrrole with formylpyrrole.
9
5.2%).
Electronic absorption spectrum (
88 (5.08), 464 (4.80), 354–367 (3.81) (CHCl ); 486
3,3',5,5'ꢀTetramethylꢀ2,2'ꢀdipyrrolylmethene hydroꢀ
λ
max, nm (log )):
ε
bromide was prepared, isolated, and identified accordꢀ
ing to [31]. Two milliliters of concentrated HBr was
added on stirring at ambient temperature to a solution
of 1.2 g (12.6 mmol) of 2,6ꢀdimethylpyrrole and 1.55 g
4
3
(
5.05), 464 (4.77), 354–366 (3.84) (DMF).
1
H NMR (500 MHz, CDCl3, , ppm): 1.96 (s,
δ
1
7
2H, CH ), 2.34 (s, 12H, CH ), 6.01 (s, 4H, CH ),
.04 (s, 2H, –CH=meso).
3
3
pyr
(
12.6 mmol) of 2ꢀformylꢀ3,4ꢀdimethylpyrrole in 20 mL
of methanol. The mixture was stirred for 2 h, the preꢀ
cipitate was separated by filtration, washed with methꢀ
anol, ether and dried at ambient temperature in air.
Yield 2.4 g (67.7%).
For C H N Zn anal. calcd. (%): C, 67.32; H,
.52; N, 12.08.
26
30
4
6
Found (%): C, 67.05; H, 6.48; N, 12.02.
Zinc(II) complex with 3,3',5,5'ꢀtetraphenylꢀ2,2'ꢀ
1H NMR (
δ, ppm): 13.12 (br s, 2H, NH), 7.09 (s,
dipyrrolylmethene (5). A mixture of solutions of 0.144 g
1
2
H, msꢀH), 6.19 (s, 2H, 4,4'ꢀH), 2.71 (s, 6H, CH ),
.37 (s, 6H, CH3).
3
(
0.321 mmol) of 3,3',5,5'ꢀtetraphenylꢀ2,2'ꢀdipyrrolylꢀ
methene in 10 mL of 1ꢀbutanol and 0.06 g (0.273 mmol)
of Zn(AcO)2 2H O in 6 mL of 1ꢀbutanol was heated
For BrC H N anal. calcd. (%): C, 55.70; H,
13
17
2
⋅
2
6
.12; N, 10.00.
Found (%): C, 55.25; H, 6.05; N, 9.89.
Synthesis of required pyrroles is described in [33].
at reflux for 1 h. The mixture was cooled, the precipiꢀ
tate was washed sequentially with hot water and ether and
dried in air. The matter was dissolved in methylene chloꢀ
ride and chromatographed on silica gel (L 100/250). The
eluate was evaporated and the complex was precipiꢀ
tated with methanol on strong cooling. Yield 0.150 g
3,3',5,5'ꢀTetraphenylꢀ2,2'ꢀdipyrrolylmethene was
prepared using procedure described in [34]. A mixture
of 0.44 g (2.02 mmol) of 3,5ꢀdiphenylpyrrole, 0.5 g
(
0.156 mmol, 97%).
(
2.02 mmol) of 2ꢀformylꢀ3,4ꢀdimethylpyrrole, 10 mL
Electronic absorption spectrum (
74 (4.70), 529 (4.88), 391–409 (3.79), 293 (4.66)
λ
max, nm (log )):
ε
of acetic acid, and 2.5 mL of acetic anhydride was
heated at reflux for 1 h. The solution became crimson
and a precipitate formed. The resultant precipitate was
separated by filtration, washed with methanol, and dried.
5
(
CHCl ); 574 (4.73), 531 (4.91), 385–408 (3.94), 291
3
(
4.73) (DMF).
1H NMR (500 MHz, CDCl3,
δ
, ppm): 6.45 (s, 4H, The acetic acid solution was poured into 200 mL of
CH ), 7.10 (s, 2H, –CH=meso), 7.46–7.50 (m, water, the precipitate was separated by filtration,
4
pyr
0H, H Ph).
For C H N Zn anal. calcd. (%): C, 82.53; H, chloroform as an eluent). Total yield is 0.7 g (77.2%).
dried, and chromatographed on silica gel (L 100/250,
66
46
4
4.83; N, 5.83.
Electronic absorption spectrum (
λ
= 532, 295 nm
max
Found (%): C, 82.17; H, 4.48; N, 5.65.
(benzene).
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 59 No. 10 2014