Paper
Dalton Transactions
J = 12.6, 8.8 Hz, 4H), 6.77 (d, J = 8.9 Hz, 2H), 3.12 (s, 6H), 1116 (m, C–O), 896, 797, 753, 694 (m, Ph–H); Elemental
2
.64 (s, 3H).
analysis (%) calculated for C H LaF N O : C, 45.27; H, 2.39;
5
4
34
21
6
8
Synthesis of 4,4,5,5,6,6,6-heptafluoro-1-azobenzene-1,3-hexa- N, 5.87; Found: C, 45.21; H, 2.38; N, 5.86.
6
7
nedione (LA). Sodium hydride (0.13 g, 5.5 mmol) and methyl
Eu(LA)
3
(H
2
O)
2
, orange solid (yield = 95%); mp 128–130 °C;
1
heptafluorobutyrate (1.25 g, 5.5 mmol) were dissolved in dry
H NMR (400 MHz, DMSO-d ) δ 7.84 (s, 9H), 7.67–7.54
6
−
1
ether (10 ml). The solution was stirred at 0–5 °C for 30 min. (m, 15H), 7.00 (s, 3H); 4.77 (s, 3H); FT-IR (KBr, cm ) 3434
Then compound A (1.12 g, 5.0 mmol) was added to the above (s, O–H), 2920 (w, C–H), 1616 (s, CvO), 1523 (m, NvN), 1486
solution. The mixture was further stirred for 16 h at room (w, CvC), 1346 (m, C–N), 1227 (s, C–F), 1116 (m, C–O), 894,
temperature. A few drops of dilute sulfuric acid were added to 791, 749, 692 (m, Ph–H); Elemental analysis (%) calculated for
the solution, which was further washed with water (3 × 15 mL).
The resultant solution was separated and dried with an- H, 2.45; N, 5.75.
hydrous MgSO . Removal of the ether afforded a crude Gd(LA) (H O)
C
54
H
34EuF21
N
6
O
8
: C, 4.86; H, 2.37; N, 5.81; Found: C, 43.45;
4
3
2
2
, yellow solid (yield = 94%); mp 130–132 °C;
−1
product, which was purified by recrystallization with ethanol FT-IR (KBr, cm ) 3448 (s, O–H), 2912 (w, C–H), 1618 (s, CvO),
to give a solid bright yellow pure product (1.41 g, 67%): mp 1523 (m, NvN), 1485 (m, CvC), 1346 (m, C–N), 1226 (s, C–F),
1
9
9–100 °C; ESI(+)-MS (m/z, methanol) = 421.2; H NMR 1116 (s, C–O), 891, 791, 749, 692 (m, Ph–H); Elemental analysis
(400 MHz, CDCl
3
) δ 15.25 (bs, 1H), 8.13 (d, J = 8.6 Hz, 2H), (%) calculated for C54
6 8
H34GdF21N O : C, 44.70; H, 2.36; N, 5.79;
8
.08–7.93 (m, 4H), 7.55–7.50 (m, 3H), 6.68 (s, 1H); FT-IR (KBr, Found: C, 44.74; H, 2.62; N, 5.78. (No NMR data due to the
−
1
cm ) 3440 (s, O–H), 2922 (w, C–H), 1635 (s, CvO), 1516 (m, paramagnetic properties of the Gd(III) ion.)
NvN), 1349 (s, C–N), 1240 (s, C–F), 1128 (s, C–O), 889, 797, Yb(LA) (H O) , yellow solid (yield = 90%); mp 131–133 °C;
50, 691 (m, Ph–H); Elemental analysis (%) calculated for H NMR (400 MHz, CDCl ) δ 9.79 (s, 6H), 8.78 (s, 6H), 8.44
: C, 51.44; H, 2.64; N, 6.67. Found: C, 51.53; (s, 6H), 7.84 (s, 9H), 6.72 (s, 3H); FT-IR (KBr, cm ) 3449
H, 2.75; N, 6.61. (s, O–H), 2920 (w, C–H), 1617 (s, CvO), 1573 (m, CvC), 1521
Synthesis of 4,4,5,5,6,6,6-heptafluoro-1-(4-dimethylamino) (m, NvN), 1343 (m, C–N), 1227 (s, C–F), 1140 (s, C–O), 891,
3
2
2
1
7
3
−
1
18 11 7 2 2
C H F N O
6
7
azobenzene-1,3-hexanedione (LB). Sodium hydride (0.13 g, 792, 753, 691 (m, Ph–H); Elemental analysis (%) calculated for
.5 mmol) and methyl heptafluorobutyrate (1.25 g, 5.5 mmol) : C, 44.21; H, 2.34; N, 5.73; Found: C, 44.04;
were dissolved in dry ether (6.5 ml). The solution was stirred at H, 2.41; N, 5.68. Orange plate crystals were obtained by slow
–5 °C for 30 min. Then B (1.33 g, 5.0 mmol) was added to the evaporation of ethanol solution. Ethanol substituted the co-
5
54 6 8
C H34YbF21N O
0
above solution and the mixture was further stirred for 16 h at ordinated water molecule in the crystal structure to give
room temperature. After the addition of a few drops of dilute Yb(LA) (CH CH OH) .
3
3
2
2
sulfuric acid, the solution was washed with water (3 × 15 mL),
separated and dried with anhydrous MgSO
concentrated and purified by column chromatography (silica) 7.77 (dd, J = 18.0, 8.6 Hz, 12H), 6.82 (d, J = 9.1 Hz, 6H), 6.36
La(LB)
3
(H
2
1
O)
2
,
deep red solid (yield
=
89%); mp
4
. The mixture was 260–263 °C; H NMR (400 MHz, DMSO-d ) δ 8.04 (s, 6H),
6
= 0.7), giving a (s, 3H), 3.07 (s, 18H); FT-IR (KBr, cm− ) 3439 (s, O–H), 2920
1
with 8 : 1 petrol/ethyl acetate as the eluent (R
pure deep red solid product (0.97 g, 42%): mp 145–147 °C; ESI (w, C–H), 1605 (s, CvO), 1573 (m, CvC), 1519 (m, NvN),
f
1
(
+)-MS (m/z, methanol) = 464.2; H NMR (400 MHz, CDCl3) 1366 (m, C–N), 1229 (m, C–F), 1139 (s, C–O), 892, 791, 750,
δ 15.36 (s, 1H), 8.08 (d, J = 8.3 Hz, 2H), 7.96 (t, J = 12.1 Hz, 4H), 622 (m, Ph–H); Elemental analysis (%) calculated for
.79 (d, J = 8.0 Hz, 2H), 6.66 (s, 1H), 3.13 (s, 6H); FT-IR (KBr, : C, 46.14; H, 3.16; N, 8.07; Found: C, 45.68;
6
60 9 8
C H49LaF21N O
−
1
cm ) 3437 (s, O–H), 2922 (m, C–H), 1596 (s, CvO), 1518 H, 3.51; N, 7.91.
(
(
m, NvN), 1448 (m, CvC), 1366 (m, C–N), 1231 (s, C–F), 1141
s, C–O), 885, 804, 744, 695 (m, Ph–H); Elemental analysis (%) 250–253 °C; H NMR (400 MHz, CDCl
Eu(LB)
3
(H
2
1
O)
2
,
deep red solid (yield
=
92%); mp
3
) δ 8.15 (d, J = 8.5 Hz,
calculated for C H F N O : C, 51.84; H, 3.48; N, 9.07. Found: 9H), 8.06–8.01 (m, 9H), 7.32 (s, 6H), 7.25–7.23 (m, 3H), 2.71
2
0
16 7 3 2
(s, 18H); FT-IR (KBr, cm− ) 3437 (s, O–H), 2917 (w, C–H), 1606
s, CvO), 1571 (m, CvC), 1518 (m, NvN), 1366 (m, C–N),
226 (s, C–F), 1141 (s, C–O), 894, 791, 750, 618 (m, Ph–H);
54 6 8
General procedure. LA (or LB) (0.20 mmol) and NaOH Elemental analysis (%) calculated for C H49EuF21N O :
1
C, 51.94; H, 3.95; N, 9.01.
(
1
6
8
Synthesis of Ln(III) complexes 1–8
(
(
0.23 mmol) were dissolved in hot ethanol (10 mL) and water C, 45.75; H, 3.14; N, 8.00; Found: C, 45.31; H, 3.43; N, 7.92.
1 mL). After the above solution was cooled down to room Orange plate crystals were obtained by slow evaporation of
3 2
temperature, LnCl ·6H O (0.067 mmol) in ethanol (10 mL) was ethanol and acetone mixed solution. Ethanol substituted the
added dropwise and the mixture was further stirred for 24 h coordinated water molecule in the crystal structure to give
(
Schemes 1 and 2). The precipitate formed after the addition Eu(LB) (CH CH OH)(H O).
3
3
2
2
of water was filtered, recrystallized from 95% ethanol and
dried in vacuum.
Gd(LB)
3
(H
2
O)
2
,
deep red solid (yield
=
89%); mp
−1
250–253 °C; FT-IR (KBr, cm ) 3449 (s, O–H), 2918 (m, C–H),
La(LA) (H O) , yellow solid (yield = 92%); mp 131–132 °C; 1605 (s, CvO), 1571 (m, CvC), 1518 (m, NvN), 1366 (m,
3
2
2
1
3
H NMR (400 MHz, CDCl ) δ 8.36–8.18 (m, 18H), 7.49 (s, 9H), C–N), 1227 (s, C–F), 1141 (s, C–O), 894, 798, 750, 619 (m,
−1
6
.68 (s, 3H); FT-IR (KBr, cm ) 3448 (s, O–H), 2915 (w, C–H), Ph–H); Elemental analysis (%) calculated for C54
6 8
H49GdF21N O :
1
634 (s, CvO), 1524 (m, NvN), 1348 (m, C–N), 1225 (m, C–F), C, 45.60; H, 3.13; N, 7.98; Found: C, 45.66; H, 3.04; N, 7.91.
Dalton Trans.
This journal is © The Royal Society of Chemistry 2016