Naphthalene amidine imide dyes by transamination of naphthalene bisimides

Article abstract of DOI:10.1002/chem.200500899

Derivatives of naphthalene-1,4,5,8-tetracarboxylic acid with amidine structures have been prepared. The light absorption of the bisimide derivatives in the UV region is shifted to the visible for the amidine imides, which also fluoresce with a large Stoke

Full text of DOI:10.1002/chem.200500899

FULL PAPER
DOI: 10.1002/chem.200500899
Naphthalene Amidine Imide Dyes by Transamination ofNaphthalene
Bisimides
Heinz Langhals* and Harald Jaschke[a]
Abstract: Derivatives ofnaphthalene-1,4,5,8-tetracarboxylic acid with amidine
structures have been prepared. The light absorption ofthe bisimide derivatives in
the UV region is shifted to the visible for the amidine imides, which also fluoresce
with a large Stokes shift. It has been shown how the bisimide–lactam rearrange-
ment can be extended to amidine structures.
Keywords: amidines
·
dyes/pig-
ments · fluorescence spectroscopy ·
heterocycles · naphthalene · UV/Vis
spectroscopy
Introduction
two imidazole moieties, instead ofthe ofrmation of 1 with
two imino groups in the molecular framework (see
Scheme 1). Ethylenediamine seems to act as an oxidant, as
has already been found in a similar reaction with perylene
dyes;[25] isomers 3 and 4 are the lower debenzocondensed
homologues ofIndanthrene Scarlet and the two pure iso-
mers Indanthrene Brilliant Red (Vat Orange 7, C.I. 71105)
and Indanthrene Bordaux (Vat Orange 15, C.I. 71100), re-
spectively. Isomers 3 and 4 are sufficiently soluble to be
used in homogeneous solution and can be separated by
column chromatography. We simultaneously condensed the
Naphthalene-1,8:4,5-tetracarboxylic bisimides (1)[1–4] are
preparatively easily accessible from the bisanhydride 2[5]
(Scheme 1) and are formally the lower analogues of the
well-known perylene dyes.[6,7] However, the light absorption
ofthe bisimides 1 is so hypsochromically shifted that they
are colourless; bisimides 1 are only weakly fluorescent (a
florescence quantum yield of 3.5% for 1a in dichlorome-
thane versus quinine sulfate[8]; see also refs. [9–11]).
It is ofinterest to produce a bathochromic shift ofthe ab-
sorption of 1 to increase its applications by exploiting its ab-
sorptivity in the visible region. Such a shift has been ob-
ꢀ
bis-anhydride 2 with a primary amine (R NH2) and ethyl-
enediamine to prepare 5 in which one ofthe carbonyl
groups of 1 has been exchanged for an imino group; com-
pound 5 was separated from the reaction products by
column chromatography (Scheme 1).
[12,13]
tained by ring-contraction ofthe imide groups
or by
substitution ofthe aromatic core with donor groups in the
2,6- and 2,7- positions.[14–21] Alternatively, one ofthe carbon-
yl groups could be replaced by an imino group; such an ar-
rangement causes a pronounced bathochromic shift in the
perylene dyes.[22–24] Anhydride imides are suitable starting
materials for the preparation of iminoimidic perylene dyes,
however, the synthesis ofthe naphthalene anhydride imide
analogues has proved difficult.
The co-condensation ofthe two amines is an acceptable
procedure with aliphatic amines, however, it is not practica-
ble for the less reactive aromatic amines because the com-
peting condensation to 3 and 4 becomes dominant. Thus, an
alternative route is required for the preparation of naphtha-
lene iminoimides 5. Perylene-3,4:9,10-tetracarboxylic bis-
imides are the larger analogues of 1. They are very stable
with respect to attack by primary amines[26] and so they are
not suitable for exchange reactions and even their hydroly-
sis[27] requires severe reaction conditions. Remarkably, the
lower naphthalene bisimide analogues (1) proved to be
Results and Discussion
The condensation ofethylenediamine with the bisanhydride
ꢀ
2 led to the isomeric bisamidines 3 and 4, characterised by
much more labile towards the exchange reactions ofthe R
N units. Thus, we first prepared naphthalene bisimides 1 by
the condensation of 2 with aromatic amines. The structure
of 1s was established by X-ray crystallography; the orienta-
tion ofthe tert-butyl groups in 1s was unambiguously deter-
mined, although the final refinement of the structure analy-
sis was unsuccessful, see Figure 1.
[a] Prof. Dr. H. Langhals, Dr. H. Jaschke
Department ofChemistry, LMU University ofMunich
Butenandtstrasse 13, 81377 Munich (Germany)
Fax : (+49)2180-77640
E-mail: Langhals@lrz.uni-muenchen.de
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one remaining carbonyl group
is conjugated to the amidine
structure. Therefore, we tested
whether the novel carboxylic
bisimide–amidine
rearrange-
ment[12] could also be carried
out with 6 in spite ofits struc-
tural differences. The rear-
rangement proceeded as a vi-
nylogous benzylic acid rear-
rangement, which has also been
verified by high-level quantum
mechanical
Thus, the involvement ofthe
two conjugating carbonyl
calculations.[29]
groups is expected to be prefer-
red determining the regioselec-
tivity ofthe reaction. Indeed,
the treatment of 5r with alco-
holic alkali gave the amidine
lactam 7r. The regioselectivity
ofthe ring contraction was de-
termined by X-ray crystallogra-
phy; the orientation ofthe car-
bonyl groups could be unam-
biguously determined, although
the final refinement of the
structure analysis of 7r was un-
successful. The formation of 7r
indicates that the novel vinylo-
gous benzylic acid rearrange-
ment is not limited to tetracar-
boxylic bisimides, but is a more
general reaction.
The bisimdes 1 form as col-
ourless crystals, although some
derivatives are reported to ex-
hibit a rose-to-red colour. This
is a consequence ofthe ofrma-
tion of the corresponding (diffi-
cult-to-remove) perylene bis-
imides as byproducts, which
have strong absorptivities of
Scheme 1. Synthesis ofnaphthalene amidine derivatives. 1, 5–7: a: R= CH(CH3)C2H5; b: R= CH(CH3)C3H7;
c: R= CH(C6H13)2; d: cyclo-C6H11; e: CH2CH2OH; f: CH2CHOHCH3; g: CH2C(CH3)(C3H7)2; h: CH2C-
(CH3)2C5H11; i: CH2C(C6H13)3; j: CH2(1-C2H5-cyclo-C6H10); k: CH2(1-C3H7-cyclo-C6H10); l: CH2C(C2H5)2C6H5;
m: CH2C(C4H9)2C6H5; n: 2,3-(CH3)C6H3; o: 2,5-(CH3)C6H3; p: 5-tBu-2-CH3C6H3; q: 2-tBu-C6H4; r: 4-tBu-
C6H4; s: 2,5-(tBu)2-C6H3.
Naphthalene iminoimides 5 with aromatic substituents R
were successfully synthesised by the reaction of 1 with ethyl-
enediamine; compare also the reaction ofthe even more re-
active alkylated phthalimide imides (five-membered ring
imides) with ethylenediamine in Gabrielꢁs synthesis.[28] Sur-
prisingly, not only the amidines 5 were obtained, but also
the byproducts 6 in which two ofthe hydrogen atoms ofthe
core were replaced by an ethylenediamine bridge; naphtha-
lene derivatives with donor groups in the 2- and 3-positions
are unknown. The formation of 6 also indicates a formal ox-
idation of 1 and corresponds to the reaction that leads to
the formation of 3 and 4 from 2.
some 105 Lmolꢀ1 cmꢀ1. These are preferentially formed if
the condensation ofamine with 2 is carried out in DMF[30]
[31]
and suppressed ifcarried out in acetic acid.
Dissolved 1
absorbs in the UV region and the structure ofthe spectra
are similar to those ofthe perylene dyes (Figure 2). A Gaus-
sian analysis (Table 1) ofthe spectrum of 1a (R value=
1.7%) indicates a vibronic pattern similar to those ofthe
perylene dyes.[32] The fluorescence of 1 is very weak.[10] Ac-
cording to Adachi et al., two overlapping electronic levels
are responsible for the fluorescence deactivation.[33]
The replacement oftwo carbonyl groups in 1 by imino
groups causes a bathochromic shift of the absorption into
the visible region (Figure 3). The absorption ofthe red cis
isomer 4 (syn) is more bathochromically shifted than the
The amidines 5 contain one complete carboxylic imide
substructure. On the opposite side ofthe naphthalene core
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Chem. Eur. J. 2006, 12, 2815 – 2824

Naphthalene Amidine Imide Dyes
FULL PAPER
Figure 3. UV/Vis absorption spectra ofnaphthalene derivatives in chloro-
form. From left to right: 1a, 3 and 4 and the fluorescence spectrum of 3.
yellow trans isomer 3 (anti). The different absorption spectra
for these isomers correspond to the different colours of the
benzo analogues of 3 and 4, respectively, the dyes Vat
Orange
7
(C.I. 71105) and Vat Orange 15 (C.I.
71100).[30,34–36] Compound 3 fluoresces with a quantum yield
of 40% and the Stokes shift is remarkable, whereas no fluo-
rescence was detected for the more bathochromically ab-
sorbing 4. This is similar to the well-known different fluores-
Figure 1. Stereo plots ofthe X-ray crystal structures ofa) 1s and b) 7r.
[37–39]
cence properties ofthe isomeric bimanes,
although in
this case the syn isomer is fluorescent and the anti isomer is
not.
The replacement ofa single carbonyl group of 1 by an
imino group is sufficient to account for most of the batho-
chromic shift of 3 and so 5 also absorbs in the visible region
(Figure 4). Compound 4 is fluorescent with a quantum yield
of20% and its Stokes shift is large. The substituent R in 5 is
useful for linking with substrates and so fluorescent labelling
is possible. The absorption ofthe byproducts 6 is shifted far
into the visible. The UV/Vis spectrum of 6 is strongly batho-
chromically shifted (500 nm) compared with 1 and struc-
Figure 2. UV/Vis absorption spectra of 1a (thick line, left) in chloroform
compared with the perylene dyes (thin line, right). The vertical bars indi-
cate the positions and intensities ofthe vibration bands according to
Gaussian analysis. Thick line in the middle: fluorescence spectrum of 1a.
Table 1. Gaussian analysis ofthe UV/Vis spectrum of 1a.
Nr.
lmax [nm]
2s2 [104 cmꢀ2
]
Emax
1
2
3
4
5
6
7
8
9
381.6
373.7
361.4
343.7
324.3
310.1
296.5
290.0
275.1
0.147
0.096
0.427
1.37
0.572
1.309
0.579
1.559
17.87
0.964
0.394
0.695
0.472
0.172
0.218
0.063
0.066
0.074
Figure 4. UV/Vis absorption spectra ofnaphthalene derivatives in chloro-
form. Absorption and fluorescence spectra of 5c (thick lines) and 6a
(thin lines in the centre). The absorption spectrum of 1a (thin line left) is
shown for comparison.
Chem. Eur. J. 2006, 12, 2815 – 2824
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2817

H. Langhals and H. Jaschke
calcd (%) for C22H22N2O4 (378.4): C 69.83, H 5.86, N 7.40; found: C
69.97, H 5.93, N 7.07.
tured in contrast to the other naphthalene derivatives 3–5.
The fluorescence of 5 (quantum yield of6%) is also struc-
tured and the Stokes shift is small compared with the other
naphthalene derivatives. The spectra of 5 indicate that the
novel substitution pattern causes a bathochromic shift simi-
lar to that ofthe well-known donor disubstitution at the 2-
and 6-positions.
2,7-Bis(2-methyl-2-propylpentyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-
tetrone (1g): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g,
10.0 mmol), 2-methyl-2-propylpentylamine (4.38 g, 30.6 mmol) and N,N-
dimethylformamide (150 mL) were refluxed for 24 h, cooled to 08C,
treated dropwise with 2N HCl (400 mL, 08C, fine, beige precipitate), stir-
red for 1 h, collected by vacuum filtration (D4 glass filter, 4.90 g, 92%,
colourless material) and purified by column chromatography (silica gel,
chloroform/acetic acid 39:1). Yield 4.7 g (88%), colourless powder, m.p.
2258C. Rf (silica gel, CHCl3)=0.29. IR (KBr): n˜ =3450 (w), 3090 (w),
2960 (s), 2932 (s), 2871 (m), 1708 (s), 1668 (s), 1651 (m), 1582 (s), 1467
(m), 1454 (s), 1426 (w), 1380 (s), 1329 (s), 1263 (w), 1246 (s), 1224 (w),
1164 (m), 1115 (w), 1077 (w), 1070 (w), 1029 (w), 988 (m), 778 (w), 717
(w) cmꢀl. 1H NMR (300 MHz, CDC13): d=8.72 (s, 4H, naphthalene),
4.17 (s, 4H, 2N-CH2), 1.41–1.19 (m, 16H, 8CH2), 0.88 (t, 12H, 4CH3),
0.85 (s, 6H, 2CH3) ppm. 13C NMR (CDC13): d=163.74, 131.02, 126.69,
126.56, 47.90, 40.68, 38.98, 24.03, 16.89, 15.02 ppm. UV/Vis (CHC13): lmax
The ring contraction that occurs in the formation of 7
from 5 causes a hypsochromic shift of the absorption: lmax
=
424 nm (Figure 5). The materials are moderately fluorescent
(F=12%) and the Stokes shift remains high.
(e)=381
(27660),
360
(23170),
342
(14650),
327
(9690 dm3 molꢀ1 cmꢀ1) nm. MS (70 eV): m/z (%): 518 (46) [M+], 475 (10),
406 (100), 294 (26), 280 (11), 249 (9), 112 (12), 71 (25), 57 (23), 55 (10).
Elemental analysis calcd (%) for C32H42N204 (518.7): C 74.10, H 8.16, N
5.40; found: C 74.16, H 8.04, N 5.58.
2,7-Bis(2,2-dimethylheptyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-tetrone
(1h): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g, 10.0 mmol),
2,2-dimethylheptylamine (4.38 g, 30.0 mmol) and acetic acid (60 mL)
were refluxed for 2.5 h, cooled, treated with 2n HCl (400 mL), stirred for
1 h (fine, beige precipitate), collected by vacuum filtration (D4 glass
filter), dried in air (1108C, 8 h, 2.4 g, 45%), dissolved in hot chloroform
(removing 150 mg ofan insoluble byproduct), treated dropwise with eth-
anol until crystallisation, left to stand for 16 h and collected by vacuum
filtration (further material can be obtained by evaporation of the mother
liquor) and purified by column chromatography (silica gel, chloroform).
Yield 1.90 g (36%), colourless powder, m.p. 1658C. Rf (silica gel,
CHCl3)=0.59. Rf (silica gel, CHCl3/acetic acid 9.75:0.25)=0.61. IR
(KBr): n˜ =3456 (m), 2957 (s), 2933 (s), 2872 (m), 2860 (m), 1705 (s), 1666
(s), 1582 (s), 1467 (m), 1453 (s), 1425 (w), 1392 (m), 1373 (s), 1330 (s),
1275 (w), 1246 (s), 1221 (m), 1167 (m), 1114 (w), 1097 (w), 1075 (w),
1023 (w), 980 (w), 880 (w), 875 (w), 807 (w), 775 (s), 770 (m), 716 (m),
645 (w), 564 (w) cmꢀl. 1H NMR (300 MHz, CDC13): d=8.74 (s, 4H, aro-
matic), 4.17 (s, 4H, 2N-CH2), 1.37 (m, 16H, 8CH2), 0.94 (s, 12H, 4CH3),
0.90 (t, 6H, 2CH3) ppm. 13C NMR (CDC13): d=163.6, 131.05, 126.68,
126.57, 49.26, 41.56, 36.69, 32.83, 26.03, 23.70, 22.70, 14.12 ppm. UV/Vis
(CHC13): lmax (e)=381 (17160), 361 (16940), 344 (12100), 242 (23280),
327 (7180 dm3 molꢀ1 cmꢀ1) nm. MS (70 eV): m/z (%) 518 (99.9) [M+], 503
(3.4) [M+ꢀCH3], 447 (4.4) [M+ꢀC5Hll], 406 (100) [M+ꢀC8H16], 393 (5.7)
[M+ꢀC9H19], 294 (22.3), 280 (6.0), 113 (5.4), 112 (5.8), 71 (17.5) [C5Hll+],
69 (6.0), 57 (21.9), 43 (7.9). Elemental analysis calcd (%) for C32H42N204
(518.7): C 74.10, H 8.16, N 5.40; found: C 74.26, H 8.36, N 5.30.
Figure 5. UV/Vis absorption and fluorescence spectra of 7a in chloroform
(thick lines). The absorption spectrum of 1a (thin line left) is shown for
comparison.
Experimental Section
2,7-Bis(1-methylpropyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-tetrone
(1a): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g, 10.0 mmol) was
dispersed in N,N-dimethylformamide (150 mL). 2-Aminobutane (2.24 g,
30.0 mmol) was added dropwise with stirring and the mixture was heated
at 1708C for 24 h, cooled to room temperature, poured into cooled 2n
HCl (400 mL, 08C) and allowed to stand for 1 h. The fine, beige precipi-
tate was collected by vacuum filtration through a D4 glass filter, dried
(8 h, 1108C), treated with
a saturated sodium carbonate solution
(400 mL), collected by vacuum filtration, washed with distilled water,
dried again (8 h, 1108C), dissolved three times in ethanol (100 mL), fil-
tered and evaporated to remove oily byproducts (yield 3.82 g). The mate-
rial exhibits a weak rose coloration as a consequence oftraces of N,N’-
bis(1-methylpropyl)perylene-3,4:9,10-tetracaboxylic bisimide as the only
detectable byproduct. These were removed by column chromatography
(silica gel, chloroform/acetic acid 39:1); chromatographic separation with
toluene gave similar results. Analytically pure material was obtained by a
subsequent extractive crystallisation[40] from ethanol. Yield 3.82 g (99%),
small, faint yellowish needles, m.p. 1928C. Rf (CHC13)=0.4. Rf (silica gel,
CHC13/acetic acid 10:1)=0.8. IR (KBr): n˜ =2967 (s), 2935 (m), 2877 (m),
1703 (s), 1664 (s), 1582 (s), 1454 (s), 1397 (s), 1380 (m), 1331 (s), 1279
(m), 1250 (s), 1216 (m), 1172 (w), 1080 (m), 784 (m), 771 (s), 735 (m),
2,7-Bis(2,2-dihexyloctyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-tetrone
(1i): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g, 10.0 mmol), 2,2-
dihexyloctylamine (9.11 g, 30.0 mmol) and N,N-dimethylformamide
(150 mL) were refluxed for 24 h, cooled for 16 h, treated at 08C with 2n
HCl (400 mL), collected by vacuum filtration, treated with boiling 10%
K2CO3 (400 mL, melting the reaction product), cooled to 08C, collected
by vacuum filtration (D4 glass filter), dried in vacuo with calcium chlo-
ride (8 h), dissolved in chloroform to remove an insoluble byproduct and
purified by column chromatography (silica gel, chloroform). Yield 6.4 g
(76%), colourless powder, m.p. 778C. Rf (silica gel, CHCl3)=0.95. Rf
(silica gel, CHCl3/acetic acid 9.75:0.25)=0.90. IR (KBr): n˜ =3449 (m),
2955 (s), 2930 (s), 2857 (s), 2362 (w), 2340 (w), 1707 (s), 1664 (s), 1634
(m), 1581 (s), 1575 (m), 1467 (m), 1455 (s), 1378 (m), 1327 (s), 1244 (s),
1221 (w), 1185 (w), 1105 (w), 1075 (w), 985 (w), 887 (w), 774 (m), 717
590 (w) cmꢀ1 1H NMR (400 MHz, CDC13): d=0.89 (t, 6H, 2CH3), 1.56
.
(d, 6H, 2CH3), 1.93 (m, 2H), 2.18 (m, 2H), 5.17 (sextet, 2H, 2CH), 8.70
(s, 4H, aromatic H) ppm. 13C NMR (CDC13): d=11.41, 17.96, 26.40,
51.90, 126.66, 126.79, 130.83, 163.33 ppm. UV/Vis (CHC13): lmax (e)=381
(47910), 360 (39040), 343 (22930), 242 (50560 dm3 molꢀ1 cmꢀ1) nm. MS
(70 eV): m/z (%): 378 (62) [M+], 349 (32) [M+ꢀC2H5], 323 (100) [M+
ꢀC4H7], 293 (13), 267 (24), 249 (29), 221 (6), 193 (3). Elemental analysis
(w) cmꢀ1 1H NMR (300 MHz, CDC13): d=0.80–0.90 (t, 18H, 6CH3),
.
1.22–1.35 (m, 52H, 26CH2), 4.11 (s, 1H, N-CH), 4.13 (s, 1H, N-CH), 4.20
(s, 2H, N-CH2), 8.75 (m, 4H, naphthalene) ppm. UV/Vis (CHC13): lmax
(e)=381 (29150), 361 (24440), 342 (14810), 327 (9550), 242
(31670 dm3 molꢀ1 cmꢀ1) nm. MS (70 eV): m/z (%) 826 (9.6) [M+], 745
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Naphthalene Amidine Imide Dyes
FULL PAPER
(18), 743 (29) [M+ꢀC6H12], 742 (18) [M+ꢀC6H13], 741 (22) [M+ꢀC6H14],
659 (9), 657 (11), 548 (11), 547 (24), 475 (11), 463 (40), 268 (63), 249 (25),
197 (13), 154 (50), 136 (52), 89 (57), 77 (100), 69 (64), 57 (60), 55 (91), 42
(81), 41 (84.0). Elemental analysis calcd (%) for C54H86N2O4 (827.3): C
78.40, H 10.48, N 3.39; found: C 77.79, H 10.18, N 3.61.
d=8.44 (s, 4H, naphthalene), 7.25–7.17 and 7.09–7.00 (2m, 10H,
2phenyl), 4.37 (s, 4H, 2N-CH2), 1.84, 1.40–1.31 and 1.20–1.116 (3m,
24H, 12CH2), 0.91 (t, 12H, 4CH3) ppm. 13C NMR (CDC13): d=163.03,
144.35, 130.58, 127.72, 127.05, 126.41, 126.15, 125.86, 48.48, 45.70, 34.75,
26.04, 23.57, 14.14 ppm. UV/Vis (CHCl3): lmax (e)=381 (19690), 361
(19470), 343 (13760), 241 (31090), 327 (7180 dm3 molꢀ1 cmꢀ1) nm. MS
(70 eV): m/z (%) 698 (3) [M+], 496 (6) [M+ꢀ202], 483 (3), 280 (3), 249
(3), 216 (45), 203 (100), 147 (43), 133 (32), 119 (28), 118 (13), 117 (14),
115 (6). Elemental analysis calcd (%) for C46H54N2O4 (698.9): C 79.05, H
7.79, N 4.01; found: C 78.76, H 7.75, N 4.07.
2,7-Bis(2-ethylcyclohexylmethyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-
tetrone (1j): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g,
10.0 mmol), 2-ethyl-1-aminomethylcyclohexane (4.33 g, 30.0 mmol) and
acetic acid (30 mL) were allowed to react as described above for 1i and
purified by column chromatography (silica gel, chloroform/acetic acid
39:1). Yield 550 mg (10.5%), m.p. 2568C. Rf (silica gel, CHCl3)=0.5. Rf
(silica gel, CHCl3/acetic acid 10:1)=0.87. IR (KBr): n˜ =2929 (m), 2860
(w), 1710 (s), 1668 (s), 1636 (w), 1582 (m), 1454 (m), 1424 (w), 1374 (m),
1351 (w), 1326 (s), 1298 (w), 1280 (w), 1248 (s), 1221 (w), 1171 (w), 989
(w), 772 (m), 716 (w) cmꢀl. 1H NMR (400 MHz, CDC13): d=8.74 (s, 4H,
aromatic), 4.19 (s, 4H, 2N-CH2), 1.56–1.36 (m, 16H, 8CH2), 1.25–1.10
(m, 8H, 4CH2), 0.96 (t, 6H, 2CH3) ppm. 13C NMR (CDC13): d=163.87,
131.05, 126.68, 126.56, 47.99, 38.78, 33.49, 26.29, 25.86, 21.54, 7.70 ppm.
UV/Vis (CHC13): lmax (e)=382 (22580), 361 (19090), 343 (11960), 326
(7780), 241 (24380 dm3 molꢀ1 cmꢀ1) nm. MS (70 eV): m/z (%) 514 (73)
[M+], 485 (4.3) [M+ꢀC2H3], 404 (100) [M+ꢀC8H14], 391 (8), 294 (31),
281 (11), 280 (10), 263 (5), 249 (6), 111 (36), 110 (22), 81 (17), 69 (39), 55
(12). Elemental analysis calcd (%) for C32H38N2O4 (514.7): C 74.68, H
7.44, N 5.44; found: C 74.82, H 7.32, N 5.59.
2,7-Bis(2,3-dimethylphenyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-te-
trone (1n): Naphthalenetetracarboxylic bisanhydride (2, 1 g, 4 mmol),
2,3-dimethylaniline (1.37 g, 10.0 mmol) and acetic acid (20 mL) were al-
lowed to react as described above for 1i. Yield 1.10 g (61%), fine, yellow
needles, m.p. >3508C. Rf (silica gel, CHCl3)=0.25. Rf (silica gel, CHCl3/
acetic acid 39:1)=0.57. IR (KBr): n˜ =2980 (w), 2924 (w), 2861 (w), 1719
(s), 1684 (s), 1585 (s), 1476 (m), 1455 (m), 1350 (s), 1255 (s), 1220 (m),
1205 (s), 1161 (w), 1125 (w), 1096 (w), 1030 (w), 988 (m), 904 (w), 885
(w), 830 (w), 792 (m), 778 (s), 750 (s), 715 (m), 611 (w) cmꢀ1 1H NMR
.
(80 MHz, CDC13): d=9.84 ppm (s, 4H, naphthalene), 8.25 (m, 6H,
2phenyl), 2.41 (s, 6H, 2CH3), 2.10 (s, 6H, 2CH3) ppm. UV/Vis (CHC13):
lmax (e)=380 (26560), 360 (23940), 342 (14780), 327 (7430), 242
(30300) nm. MS (70 eV): m/z (%) 474 (87) [M+], 459 (38) [M+ꢀCH3],
457 (100), 441 (6), 425 (7). Elemental analysis calcd (%) for C30H22N2O4
(474.5): C 75.94, H 4.67, N 5.90; found: C 75.61, H 4.63, N 5.76.
2,7-Bis(2-propylcyclohexylmethyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-
tetrone (1k): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g,
10.0 mmol), 2-propyl-1-aminomethylcyclohexane (4.75 g, 30.0 mmol) and
acetic acid (30 mL) were allowed to react as described above for 1i and
purified by column chromatography (silica gel, chloroform) and recrystal-
lisation from chloroform/ethanol. Yield 0.78 g (15%), colourless, small
leaflets, m.p. 2278C. Rf (CHCl3)=0.80. IR (KBr): n˜ =3441 (m), 2931 (s),
2867 (s), 1710 (s), 1667 (s), 1634 (w), 1582 (s), 1454 (s), 1435 (m), 1423
(w), 1378 (m), 1326 (s), 1287 (w), 1245 (s), 1221 (m), 1171 (m), 1155 (w),
2,7-Bis(2,5-dimethylphenyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-te-
trone (1o): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g,
10.3 mmol), 2,5-dimethylaniline (4.97 g, 41.0 mmol) and acetic acid
(100 mL) were allowed to react as described above for 1i and purified by
extractive recrystallisation[40] from ethanol. Yield 2.54 g (52%), m.p. >
3508C. Rf (silica gel, CHCl3/acetone 15:1)=0.49. IR (KBr): n˜ =3435 (m,
br), 2924 (m), 1715 (s), 1679 (s), 1582 (m), 1509 (m), 1448 (m), 1344 (s),
1251 (s), 1199 (m), 1148 (w), 1120 (w), 982 (w), 930 (w), 886 (w), 818 (w),
772 (m), 754 (m) cmꢀ1. 1H NMR (80 MHz, CDC13): d=8.86 (s, 4H, naph-
thalene), 7.33 (d, J=7.8 Hz, 2H, phenyl), 7.20 (d, J=7.6 Hz, 2H,
phenyl), 7.04 (s, 2H, phenyl), 2.40 (s, 6H, 2CH3), 2.15 (s, 6H,
2CH3) ppm. 13C NMR (CDC13): d=166.6 (4C=O), 144.3 (2C-phenyl),
137.0, 134.3, 132.6, 132.5, 130.9, 130.8, 130.0, 128.8, 128.7, 125.3, 123.4,
123.1 (10C-phenyl and 10C-naphthalene), 20.9 (2CH3), 17.1
(2CH3) ppm. UV/Vis (CHC13): lmax (e)=380.1 (26050), 359.2 (23620),
341.9 (14540), 274.6 (7040), 269.8 (6600 dm3 molꢀ1 cmꢀ1) nm. MS (70 eV):
m/z (%) 475 (24) [M++1], 474 (80) [M+], 459 (27) [M+ꢀCH3], 458 (29),
457 (100), 441 (4), 439 (6), 429 (4), 425 (7), 413 (3), 310 (2), 308 (2), 237
(3) [M2+]. Elemental analysis calcd (%) for C30H22N2O4 (474.5): C 75.94,
H 4.67, N 5.90; found: C 75.61, H 4.63, N 5.76.
1142 (w), 1118 (w), 1095 (w), 1065 (w), 1016 (w), 993 (w), 772 (s) cmꢀ1
.
1H NMR (400 MHz, CDC13): d=8.72 (s, 4H, naphthalene), 4.40 (s, 4H,
2N-CH2), 1.50–1.23 (m, 20H, 10CH2), 1.24–1.10 (m, 8H, 4CH2), 0.91 (t,
6H, 2CH3) ppm. 13C NMR (CDCl3): d=163.84, 131.04, 126.70, 126.57,
48.43, 38.97, 36.39, 33.99, 25.86, 21.59, 16.47, 15.13 ppm. MS (70 eV): m/z
(%) 542 (83) [M+], 499 (3) [M+ꢀC3H7], 418 (100) [M+ꢀC9H16], 405 (6)
[M+ꢀCl0H17], 294 (20) [418ꢀC9H16]. Elemental analysis calcd (%) for
C34H42N2O4 (542.7): C 75.24, H 7.80, N 5.20; found: C 74.78, H 7.52, N
5.22.
2,7-Bis(2-ethyl-2-phenylbutyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-te-
trone (1l): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g,
10.0 mmol), 2-ethyl-2-phenylbutylamine (4.20 g, 20.0 mmol) and acetic
acid (60 mL) were allowed to react as described above for 1i, and finally
extracted with ethanol. Yield 80 mg (1.3%), m.p. 2208C. Rf (silica gel,
CHC13)=0.38. Rf (silica gel, CHCl3/acetic acid 9.75:0.25)=0.57. IR
(KBr): n˜ =3447 (m), 2968 (m), 2950 (w), 2882 (w), 1709 (s), 1669 (s),
1651 (m), 1582 (m), 1499 (w), 1454 (m), 1372 (w), 1326 (s), 1247 (s), 1166
(w), 1100 (w), 1083 (w), 1025 (w), 1004 (w), 770 (w), 759 (m), 701
2,7-Bis(5-tert-butyl-2-methylphenyl)benzo[lmn][3,8]phenanthroline-
1,3,6,8-tetrone (1p): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g,
10.0 mmol), 5-tert-butyl-2-methylaniline (5.00 g, 30.0 mmol) and acetic
acid (20 mL) were allowed to react as described above for 1i. Yield 3.5 g
(61%), fine, yellow needles, m.p. 3188C. Rf (silica gel, CHC13)=0.46. Rf
(silica gel, CHCl3/acetic acid 39:1)=0.57. IR (KBr): n˜ =2960 (m), 2920
(m), 2870 (m), 1725 (s), 1680 (s), 1585 (s), 1520 (m), 1450 (m), 1420 (w),
1379 (m), 1350 (s), 1251 (s), 1215 (m), 1200 (s), 1178 (m), 1135 (w), 1125
(w), 1035 (w), 985 (m), 925 (w), 885 (m), 835 (m), 824 (m), 770 (s), 755
(m) cmꢀ1 1H NMR (400 MHz, CDC13): d=8.44 (s, 4H, naphthalene),
.
7.26–7.19 and 7.11–7.00 (2”m, 10H, 2phenyl), 4.37 (s, 4H, 2N-CH2),
2.13–1.85 (m, 20H, 4C2H5) ppm. UV/Vis (CHCl3): lmax (e)=381 (19800),
361 (19660), 345 (13740), 326 (82230), 240 (27990 dm3 molꢀ1 cmꢀ1) nm.
MS (70 eV): m/z (%) 586 (19) [M+], 557 (3) [M+ꢀethyl], 440 (13) [M+
ꢀPh(C2H5)C=CH-CH3], 427 (10), 160 (48), 147 (100), 146 (26), 105 (87),
91 (76). Elemental analysis calcd (%) for C38H38N2O4 (586.7): C 77.79, H
6.53, N 4.77; found: C 77.27, H 6.30, N 4.71.
1
(s), 714 (w), 680 (w), 650 (m), 623 (w) cmꢀ1. H NMR (80 MHz, CDC13):
d=9.83 (s, 4H, naphthalene), 8.29 (m, 6H, 2phenyl), 2.18 (s, 6H, 2CH3),
1.38 (s, 18H, 2C(CH3)3) ppm. UV/Vis (CHC13): lmax (e)=380 (27130),
360 (24410), 343 (14920), 326 (7460), 240 (36720 dm3 molꢀ1 cmꢀ1) nm. MS
(70 eV): m/z (%) 558 (31) [M+], 543 (100) [M+ꢀCH3], 264 (12). Elemen-
tal analysis calcd (%) for C36H34N2O4 (558.7): C 77.40, H 6.13, N 5.01;
found: C 77.69, H 6.11, N 5.20.
2,7-Bis(2-butyl-2-phenylhexyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-te-
trone (1m): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g,
10.0 mmol), 2-butyl-2-phenylhexylamine (7.14 g, 30.0 mmol) and N,N-di-
methylformamide (150 mL) were allowed to react as described above for
1a. Yield 6.0 g (84%), fine, colourless needles, m.p. 1628C. Rf (silica gel,
CHCl3)=0.68. Rf (silica gel, CHCl3/acetic acid 39:1)=0.66. IR (KBr): n˜ =
2957 (s), 2935 (m), 2871 (m), 1710 (s), 1671 (s), 1602 (w), 1582 (m), 1499
(w), 1454 (m), 1420 (w), 1378 (m), 1326 (s), 1247 (s), 1222 (w), 1161 (w),
2,7-Bis(2-tert-butylphenyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-tetrone
(1q): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g, 10.0 mmol), 2-
tert-butylaniline (4.57 g, 30.0 mmol) and acetic acid (20 mL) were allowed
to react as described for 1i. Yield 4.88 g (90%), colourless powder ofa
1:1 mixture ofthe cis and trans atropic isomers. The two isomers were
separated by column chromatography (silica gel, CHCl3).
1009 (w), 763 (m), 698 (m), 582 (w) cmꢀ1 1H NMR (400 MHz, CDC13):
.
Chem. Eur. J. 2006, 12, 2815 – 2824
ꢀ 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemeurj.org
2819

H. Langhals and H. Jaschke
Isomer I (trans, anti[41]). Yield 1.4 g (26%), colourless powder, m.p. 332–
3388C. Rf (silica gel, CHCl3)=0.30. Rf (silica gel, CHCl3/acetic acid
39:1)=0.54. IR (KBr): n˜ =3424 (m), 2965 (m), 1912 (m), 2880 (m), 1714
(s), 1676 (s), 1581 (s), 1490 (m), 1447 (m), 1365 (m), 1344 (s), 1249 (s),
1216 (m), 1200 (m), 1148 (w), 1121 (w), 1085 (w), 1054 (w), 982 (m), 880
(w), 866 (m), 830 (w), 802 (w), 772 (s), 754 (s), 716 (s), 686 (w), 667 (w),
thalene-1,8:4,5-tetracarboxylic bisanhydride (2, 500 mg, 1.9 mmol) and
1,2-diaminoethane (560 mg, 9.3 mmol) in quinoline (5 mL) were heated
at 1808C for 2 h, cooled to room temperature, treated with ethanol
(10 mL) and poured into 2n HCl (50 mL). This mixture was stirred for
1 h, allowed to stand for 1 h, collected by vacuum filtration, dried in air
at 1008C, extracted with chloroform and purified by column chromatog-
raphy (silica gel, chloroform/acetic acid 10:1). Dione 3 was obtained as
the first yellow and yellow fluorescent fraction and dione 4 as the second
nonfluorescent red one. Both fractions were separately further purified
by column chromatography (silica gel, CHCl3/acetone 5:1) and by extrac-
tive recrystallisation[40] from ethanol.
629 (m) cmꢀ1 1H NMR (600 MHz, CDC13): d=8.84 (s, 4H, naphtha-
.
lene), 7.69/7.67 (d, 2H, phenyl), 7.46 (t, 2H, phenyl), 7.36 (t, 2H,
phenyl), 7.02/7.01 (d, 2H, phenyl), 1.29 (s, 18H, 6CH3) ppm. 13C NMR
(CDCl3): d=163.74, 147.05, 132.48, 131.48, 130.74, 129.52, 129.44, 127.47,
127.38, 127.12, 31.73 ppm. UV/Vis (CHC13): lmax (e)=381 (28080), 360
(24290), 343 (14740), 326 (7580), 242 (26140 dm3 molꢀ1 cmꢀ1) nm. MS
(70 eV): m/z (%) 515 (4) [M+], 473 (100) [M+ꢀC(CH3)3]. Elemental
analysis calcd (%) for C34H30N2O4 (530.6): C 76.96, H 5.70, N 5.28;
found: C 77.34, H 5.86, N 4.98.
Dione 3: Yield 98 mg (17%), m.p. >3508C. Rf (silica gel, CHCl3/acetone
5:1)=0.24. IR (KBr): n˜ =3168 (m), 2925 (m), 2855 (m), 1712 (s, br), 1583
(m), 1551 (s), 1503 (s), 1470 (m), 1417 (s), 1393 (s), 1360 (s), 1338 (m),
1277 (s), 1245 (s), 1229 (m), 1110 (w), 1083 (w), 1067 (m), 1059 (s), 978
Isomer II (cis, syn[40]). Yield 1.28 g (23.5%), colourless, fine needles, m.p.
3338C. Rf (silica gel, CHCl3)=0.11. Rf (silica gel, CHCl3/acetic acid
9.75:0.25)=0.54. IR (KBr): n˜ =3424 (w), 2965 (m), 2912 (m), 2880 (w),
1714 (s), 1676 (s), 1581 (s), 1490 (m), 1442 (m), 1365 (m), 1344 (s), 1249
(s), 1216 (m), 1200 (m), 1147 (w), 1121 (w), 1089 (w), 1054 (w), 982 (m),
880 (w), 866 (m), 832 (w), 802 (w), 722 (s), 754 (m), 716 (m), 682 (w),
(m), 910 (w), 867 (m), 800 (w), 765 (s), 749 (m), 730 (m) cmꢀ1 1H NMR
.
(CDCl3): d=8.90 (d, J=7.7 Hz, 2H, naphthalene), 8.78 (d, J=7.7 Hz,
2H, naphthalene), 7.95 (d, J=1.4 Hz, 2H, amidine), 7.45 (d, J=1.7 Hz,
2H, amidine) ppm. UV (CHCl3): lmax (e)=448.1 (19050), 377.8 (8610),
364.9 (sh) (4700 dm3 molꢀ1 cmꢀ1) nm. Fluorescence (CHCl3): lmax
=
544 nm. Fluorescence quantum yield (CHCl3, E=0.0364 cmꢀ1
, lexcit
=
670 (w), 629 (m) cmꢀ1 1H NMR (400 MHz, CDC13): d=8.84 (s, 4H,
.
430 nm, reference: perylene-3,4,9,10-tetracarboxylic tetramethyl ester
with F=1.0[42])=0.16. MS (70 eV): m/z (%) 313 (17) [M++1], 312 (100)
[M+], 285 (7) [M+ꢀHCN], 230 (4), 202 (3), 188 (3), 176 (3), 156 (6)
[M2+]. Elemental analysis calcd (%) for C18H8N4O2 (312.3): C 69.23, H
2.56, N 17.95; found: C 69.42, H 2.72, N 17.90.
naphthalene), 7.70/7.68 (d, 2H, phenyl), 7.48 (t, 2H, phenyl), 7.37 (t, 2H,
phenyl), 7.06/7.04 (d, 2H, phenyl), 1.31 (s, 18H, 6CH3) ppm. 13C NMR
(CDC13): d=163.74, 147.11, 132.56, 131.49, 130.79, 129.56, 129.40, 127.51,
127.31, 127.10, 31.79 ppm. UV/Vis (CHC13): lmax.(e)=381 (28220), 360
(24690), 342 (14880), 326 (7500), 241 (36560 dm3 molꢀ1 cmꢀ1) nm. MS
(70 eV): m/z (%) 515 (4) [M+], 473 (100) [M+ꢀC(CH3)3]. Elemental
analysis calcd (%) for C34H30N2O4 (530.6): C 76.96, H 5.70, N 5.28;
found: C 76.55, H 5.70, N 5.31.
Dione 4: Yield 47 mg (8%), m.p. >3508C. Rf (silica gel, CHCl3/acetone
5:1)=0.06. Rf (silica gel, CHCl3/acetic acid 10:1)=0.28. IR (KBr): n˜ =
3162 (w), 2925 (w), 2855 (w), 1712 (s), 1583 (w), 1549 (m), 1488 (w), 1469
(w), 1421 (m), 1389 (m), 1360 (m), 1285 (s), 1279 (s), 1233 (w), 1216 (m),
1185 (w), 1152 (w), 1076 (w), 893 (w), 862 (w), 804 (w), 760 (m), 749 (m),
2,7-Bis(4-tert-butylphenyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-tetrone
(1r): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g, 10.0 mmol), 4-
tert-butylaniline (4.75 g, 30.0 mmol) and acetic acid (20 mL) were allowed
to react as described above for 1i, then dissolved in chloroform and pre-
cipitated with ethanol. Yield 2.72 g (50%), yellow, fine crystals, m.p. >
3508C. Rf (silica gel, CHCl3)=0.32. Rf (silica gel, CHCl3/acetic acid
9.75:0.25)=0.57. IR (KBr): n˜ =2963 (m), 2906 (w), 2870 (w), 1718 (s),
1676 (s), 1653 (w), 1582 (m), 1515 (m), 1506 (w), 1447 (m), 1365 (m),
1347 (s), 1247 (s), 1198 (m), 1105 (m), 982 (m), 862 (m), 835 (m), 769 (s),
744 (m), 709 (w) cmꢀ1 1H NMR (CDCl3): d=8.95 (s, 2H, naphthalene),
.
8.73 (s, 2H, naphthalene), 7.90 (d, J=1.5 Hz, 2H, amidine), 7.41 (d, J=
1.6 Hz, 2H, amidine) ppm. UV (CHCl3): lmax (e)=510.7 (8340), 374.9
(3930), 351.9 (5690 dm3 molꢀ1 cmꢀ1) nm. UV (H2SO4): lmax =451.9, 400.1,
382.8 nm. Fluorescence (H2SO4): lmax =536.7 nm. MS (70 eV): m/z (%)
313 (17) [M++1], 312 (100) [M+], 285 (6) [M+ꢀHCN], 230 (6), 202 (3),
188 (3), 176 (2), 156 (6) [M2+]. Elemental analysis calcd (%) for
C18H8N4O2 (312.3): C 69.23, H 2.56, N 17.95; found: C 68.90, H 2.65, N
17.71.
755 (m), 716 (m), 699 (w), 561 (m), 465 (w) cmꢀ1 1H NMR (400 MHz,
.
CDC13): d=1.40 (s, 18H, 6CH3), 7.27 (dd, 3J=8.40 Hz, 4Jꢁ0.5 Hz,
2-(1-Methylpropyl)-benzo[lmn]imidazolo[1,2-j][3,8]phenanthrolin-1,3,6-
trione (5a): Method 1: Naphthalene-1,8:4,5-tetracarboxylic bisanhydride
(2, 1.4 g, 5.2 mmol), 1,2-diaminoethane (470 mg, 7.8 mmol) and 2-amino-
butane (570 mg, 7.8 mmol) in quinoline (30 mL) were heated at 1808C
for 2 h, cooled to room temperature, and poured into a mixture of etha-
nol (50 mL) and 2n HCl (100 mL). The yellowish-orange precipitate was
allowed to stand for 1 h and collected by vacuum filtration through a D4
glass filter, dried in air (12 h, 1008C), extracted with chloroform and the
chloroform phase purified by column chromatography (silica gel, CHCl3/
acetone 5:1). The reaction product was obtained as the first yellow band.
Analytically pure material was prepared by further column chromatogra-
phy (silica gel, CHCl3/acetone 15:1) and extractive recrystallisation[40]
from petroleum ether. Yield 90 mg (5%). Method 2: Naphthalene-
1,8:4,5-tetracarboxylic bisanhydride (2, 1.4 g, 5.2 mmol), 1,2-diamino-
ethane (470 mg, 7.8 mmol) and 2-aminobutane (570 mg, 7.8 mmol) in
N,N’-dimethylformamide (70 mL) were refluxed for 2 h. The solvent was
removed in vacuo and the residue purified as described in method 1.
Yield 380 mg (21%) of 4a, m.p. 2658C. Rf (silica gel, CHCl3/acetone
5:1)=0.75. IR (KBr): n˜ =3435 (m, br), 2969 (w), 2947 (w), 2875 (w), 1706
(s), 1667 (s), 1618 (w), 1580 (w), 1553 (w), 1510 (w), 1412 (m), 1380 (w),
1342 (s), 1282 (s), 1245 (m), 1150 (w), 1076 (w), 974 (w), 880 (w), 767
3
4
AA’BB’ type, 4H, 4CH), 7.60 (dd, J=8.40 Hz, Jꢁ0.5 Hz, AA’BB’ type,
4H, 4CH), 8.84 (s, 4H, 4CH) ppm. 13C NMR (CDCl3): d=31.35, 34.83,
126.58, 127.04, 127.15, 127.77, 131.38, 131.71, 152.05, 163.03 ppm. UV/Vis
(CHC13): lmax (e)=380 (28070), 360 (25270), 343 (15750), 325 (7240),
241 (34130 dm3 molꢀ1 cmꢀ1) nm. MS (70 eV): m/z (%) 531 (55) [M+], 515
(32) [M+ꢀCH3], 475 (28) [M+ꢀC(CH3)3]. Elemental analysis calcd (%)
for C34H30N2O4 (530.6): C 76.96, H 5.84, N 7.71; found: C 77.25, H 5.98,
N 7.79.
2,7-Bis(2,5-di-tert-butylphenyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-te-
trone (1s): Naphthalenetetracarboxylic bisanhydride (2, 2.75 g,
10.0 mmol), 2,5-di-tert-butylaniline (4.17 g, 20.0 mmol) and acetic acid
(60 mL) were allowed to react as described above for 1i. Yield 3.43 g
(52%), fine, pale yellow needles, m.p. >2508C. Rf (silica gel, CHCl3)=
0.73. Rf (silica gel, CHCl3/acetic acid 39:1)=0.69. IR (KBr): n˜ =2963 (m),
2870 (w), 1716 (s), 1680 (s), 1616 (w), 1583 (m), 1502 (w), 1447 (w), 1394
(w), 1364 (m), 1343 (s), 1251 (s), 1200 (m), 981 (w), 828 (m), 772 (m), 644
(w) cmꢀ1 1H NMR (400 MHz, CDC13): d=0.89 (t, 6H, 2CH3), 1.56 (d,
.
6H, 2CH3), 1.93 (m, 2H), 2.18 (m, 2H), 5.17 (sextet, 2H, 2CH), 8.70 (s,
4H, aromatic) ppm. 13C NMR (CDC13): d=11.41, 17.96, 26.40, 51.90,
126.66, 126.79, 130.83, 163.33 ppm. UV/Vis (CHC13): lmax (e)=381
(m), 751 (m) cmꢀ1 1H NMR (CDCl3): d=8.88 (d, J=7.6 Hz, 1H, naph-
.
(24980),
360
(22910),
343
(14890),
328
(8400),
242
(40110 dm3 molꢀ1 cmꢀ1) nm. MS (70 eV): m/z (%) 642 (1) [M+], 627 (7)
[M+ꢀCH3], 585 (100) [M+ꢀC(CH3)3], 528). Elemental analysis calcd
(%) for C42H46N2O4 (642.8): C 78.47, H 7.21, N 4.36; found: C 77.48, H
7.28, N 4.32.
thalene), 8.75 (d, J=7.6 Hz, 1H, naphthalene), 8.72 (s, 2H, naphthalene),
7.93 (d, J=1.6 Hz, 1H, amidine), 7.42 (d, J=1.6 Hz, 1H, amidine), 5.18
(mc, 1H, CH), 2.17 (mc, 1H, CH2), 1.97 (mc, 1H, CH2), 1.57 (d, J=
7.0 Hz, 3H, CH3), 0.91 (t, J=7.5 Hz, 3H, CH3) ppm. 13C NMR (CDCl3):
d=163.4 (C=O), 163.2 (C=O), 158.3 (C=O), 144.5 (C=N), 133.0 (C-ami-
dine), 132.0, 131.9, 130.5, 128.8, 127.5, 126.3, 125.4, 125.3, 124.6, 124.1
Benzo[lmn]bisimidazo[2,1-b:2’,1’-i]phenanthroline-6,12-dione (3) and
benzo[lmn]bisimidazo[2,1-b:2’,1’-j]phenanthroline-3,6-dione (4): Naph-
2820
www.chemeurj.org
ꢀ 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Eur. J. 2006, 12, 2815 – 2824

Naphthalene Amidine Imide Dyes
FULL PAPER
(10ꢀC-naphthalene), 116.3 (C-amidine), 51.9 (CH), 26.5 (CH2), 18.0
(CH3), 11.5 (CH3) ppm. UV (CHCl3): lmax (e)=436.1 (8010), 377.0
(w), 1068 (w), 976 (w), 882 (w), 768 (m), 751 (m) cmꢀ1 1H NMR
.
(CDCl3): d=8.87 (d, J=7.7 Hz, 1H, naphthalene), 8.74 (d, J=7.7 Hz,
1H, naphthalene), 8.72 (s, 2H, naphthalene), 7.92 (d, J=1.7 Hz, 1H, ami-
dine), 7.42 (d, J=1.5 Hz, 1H, amidine), 5.01 (mc, 1H, CH), 2.52 (mc, 2H,
CH2), 1.89 (mc, 2H, CH2), 1.74 (mc, 2H, CH2), 1.43 (mc, 2H, CH2), 1.33
(mc, 2H, CH2) ppm. 13C NMR (CDCl3): d=163.3 (C=O), 163.1 (C=O),
158.3 (C=O), 144.5 (C=N), 133.0 (C-amidine), 132.0, 131.9, 130.4, 129.0,
127.5, 126.2, 125.3, 125.2, 124.5, 124.3, (10C-naphthalene), 116.2 (C-ami-
dine), 54.4 (CH), 29.1 (2CH2), 26.5 (2CH2), 25.3 (CH2) ppm. UV
(CHCl3): lmax (e)=436.1 (9670), 377.1 (8470), 360.4 (8470), 346.8 (8240),
(7310), 359.0 (6700 dm3 molꢀ1 cmꢀ1) nm. Fluorescence (CHCl3): lmax
=
546 nm. Solid-state fluorescence: lmax =571 nm. MS (70 eV): m/z (%) 346
(4) [M++1], 345 (72) [M+], 316 (25) [M+ꢀC2H5], 289 (100) [M+ꢀC4H8],
272 (23), 244 (14), 218 (6), 190 (5). Elemental analysis calcd (%) for
C20H15N3O3 (345.4): C 69.56, H 4.38, N 12.17; found: C 69.25, H 4.43, N
11.87.
2-(1-Methylbutyl)benzo[lmn]imidazolo[1,2-j][3,8]phenanthroline-1,3,6-
trione (5b): Naphthalene-1,8:4,5-tetracarboxylic bisanhydride (2, 1.4 g,
5.2 mmol), 1,2-diaminoethane (470 mg, 7.8 mmol) and 2-aminopentane
(680 mg, 7.8 mmol) in N,N’-dimethylformamide (70 mL) were allowed to
react (4 h) and the product purified as described above for 5a, method 2.
Yield 210 mg (11%), m.p. 2048C. Rf (silica gel, CHCl3/acetone 5:1)=
0.58. IR (KBr): n˜ =3432 (m, br), 2960 (m), 2931 (m), 2859 (w), 1706 (s),
1666 (s), 1616 (w), 1580 (m), 1552 (w), 1508 (w), 1439 (w), 1410 (m),
1385 (w), 1344 (s), 1277 (s), 1241 (s), 1088 (w), 880 (w), 766 (m), 752
330.2
(sh)
(7260),
299.2
(14050),
288.6
(13510),
263.6
(15180 dm3 molꢀ1 cmꢀ1) nm. Fluorescence (CHCl3): lmax =552 nm. Solid-
state fluorescence: lmax =571 nm. MS (70 eV): m/z (%) 372 (14) [M++1],
371 (60) [M+], 290 (100) [M+ꢀC6H9], 289 (87) [M+ꢀC6H10], 272 (11),
245 (6), 244 (6), 218 (4). Elemental analysis calcd (%) for C22H17N3O3
(371.4): C 71.15, H 4.61, N 11.31; found: C 70.79, H 4.52, N 11.30.
2-(2-Hydroxyethyl)benzo[lmn]imidazolo[1,2-j][3,8]phenanthroline-1,3,6-
trione (5e): Naphthalene-1,8:4,5-tetracarboxylic bisanhydride (2, 1.4 g,
5.2 mmol), 1,2-diaminoethane (470 mg, 7.8 mmol) and 2-aminoethanol
(480 mg, 7.8 mmol) in DMF (70 mL) were allowed to react (4 h) and the
product purified as described above for 5a, method 2 (silica gel, CHCl3/
ethanol 10:1 and silica gel, CHCl3/acetone 5:1 to remove two yellow fore-
runs). Yield 280 mg (16%), m.p. 3028C. Rf (silica gel, CHCl3/ethanol
10:1)=0.52. IR (KBr): n˜ =3428 (s, br), 2926 (w), 1706 (s), 1665 (s), 1616
(w), 1580 (m), 1553 (w), 1508 (w), 1480 (w), 1438 (w), 1410 (m), 1344
(m), 1284 (s), 1241 (m), 1175 (w), 1054 (w), 971 (w), 874 (w), 766 (m),
(m) cmꢀ1 1H NMR (CDCl3): d=8.90 (d, J=7.6 Hz, 1H, naphthalene),
.
8.79 (d, J=7.6 Hz, 1H, naphthalene), 8.75 (s, 2H, naphthalene), 7.95 (d,
J=1.6 Hz, 1H, amidine), 7.45 (d, J=1.6 Hz, 1H, amidine), 4.20 (t, J=
7.6 Hz, 2H, CH2), 1.75 (mc, 2H, CH2), 1.41 (mc, 4H, CH2), 0.93 (t, J=
7.1 Hz, 3H, CH3) ppm. 13C NMR (CDCl3): d=162.9 (C=O), 162.7 (C=
O), 158.2 (C=O), 144.5 (C=N), 133.1 (C-amidine), 132.0, 131.9, 130.5,
128.4, 127.5, 126.5, 125.6, 124.7, 123.8 (10C-naphthalene), 116.3 (C-ami-
dine), 40.9 (CH2), 29.2 (CH2), 27.8 (CH2), 22.4 (CH2), 13.9 (CH3) ppm.
UV (CHCl3): lmax (e)=436.9 (7230), 377.3 (6490), 359.5
(6060 dm3 molꢀ1 cmꢀ1) nm. Fluorescence (CHCl3): lmax =541 nm. Solid-
state fluorescence: lmax =573 nm. MS (70 eV): m/z (%) 360 (24) [M++1],
359 (100) [M+], 342 (6) [M+ꢀOH], 303 (23) [M+ꢀC4H8], 290 (25), 289
(60) [M+ꢀC5H10], 272 (12), 244 (8). Elemental analysis calcd (%) for
C21H17N3O3 (359.4): C 70.18, H 4.77, N 11.69; found: C 70.15, H 4.87, N
11.53.
754 (w) cmꢀ1 1H NMR (CDCl3): d=8.85 (d, J=7.7 Hz, 1H, naphtha-
.
lene), 8.75 (d, J=7.6 Hz, 1H, naphthalene), 8.71 (d, J=7.6 Hz, 2H, naph-
thalene), 7.89 (d, J=1.4 Hz, 1H, amidine), 7.39 (d, J=1.4 Hz, 1H, ami-
dine), 4.42 (t, J=5.3 Hz, 2H, CH2), 3.95 (t, J=5.0 Hz, 2H, CH2) ppm. 13C
NMR (CDCl3): d=163.6 (C=O), 142.3 (C=N), 140.3, 136.9, 135.8, 133.2,
(C-amidine), 132.3, 132.0, 130.8, 128.0, 127.6, 126.8, 125.3, 123.4, (10C-
naphthalene), 116.4 (C-amidine), 61.4 (CH2), 43.0 (CH2) ppm. UV
(CHCl3): lmax (e)=439.0 (8010), 377.5 (7390), 360.1 (6850), 347.1 (6660),
2-(1-Hexylheptyl)benzo[lmn]imidazolo[1,2-j][3,8]phenanthroline-1,3,6-
trione (5c): Naphthalene-1,8:4,5-tetracarboxylic bisanhydride (2, 1.4 g,
5.2 mmol), 1,2-diaminoethane (470 mg, 7.8 mmol) and 7-aminotridecane
(1.56 g, 7.8 mmol) in N,N’-dimethylformamide (70 mL) were allowed to
react (4 h) and the product purified as described above for 5a, method 2.
Yield 390 mg (16%), thin needles from chloroform or long needles from
DMF, m.p. 1088C. Rf (silica gel, CHCl3/acetone 5:1)=0.85. IR (KBr): n˜ =
3427 (m, br), 2956 (m), 2928 (s), 2857 (m), 1707 (s), 1665 (s), 1616 (w),
1578 (w), 1552 (w), 1509 (w), 1458 (w), 1433 (w), 1410 (m), 1379 (w),
1342 (s), 1280 (s), 1244 (s), 1179 (w), 1104 (w), 1068 (w), 973 (w), 875
331.0
(sh)
(5420),
299.4
(11900),
289.7
(11670),
263.0
(12810 dm3 molꢀ1 cmꢀ1) nm. Fluorescence (CHCl3): lmax =555 nm. Solid-
state fluorescence: lmax =575 nm. MS (70 eV): m/z (%) 334 (9) [M++1],
333 (35) [M+], 304 (5), 303 (14) [M+ꢀCH2O], 302 (25) [M+ꢀCH2OH],
290 (100), 289 (27) [M+ꢀC2H4OH], 272 (22), 244 (10), 218 (7), 191 (4).
Elemental analysis calcd (%) for C18H11N3O4 (333.3): C 64.87, H 3.33, N
12.61; found: C 64.57, H 3.24, N 12.55.
2-(2-Hydroxypropyl)benzo[lmn]imidazolo[1,2-j][3,8]phenanthroline-
1,3,6-trione (5 f): Naphthalene-1,8:4,5-tetracarboxylic bisanhydride (2,
1.4 g, 5.2 mmol), 1,2-diaminoethane (470 mg, 7.8 mmol) and 1-aminopro-
pan-2-ol (590 mg, 7.8 mmol) in DMF (70 mL) were allowed to react (4 h)
and the product purified as described above for 5a, method 2 (silica gel,
CHCl3/ethanol 5:1 and silica gel, CHCl3/ethanol 10:1) and extractive[40]
recrystallisation from methanol. Yield 570 mg (32%), m.p. 2788C. Rf
(silica gel, CHCl3/ethanol 10:1)=0.14. IR (KBr): n˜ =3436 (s, br), 2929
(w), 1707 (s), 1666 (s), 1611 (m), 1581 (w), 1553 (w), 1509 (w), 1438 (w),
1411 (m), 1386 (w), 1351 (m), 1286 (s), 1243 (m), 1067 (w), 981 (w), 767
(w), 768 (m), 748 (m) cmꢀ1 1H NMR (CDCl3): d=8.88 (d, J=7.6 Hz,
.
1H, naphthalene), 8.73 (brs, 3H, naphthalene), 7.93 (d, J=1.6 Hz, 1H,
amidine), 7.43 (d, J=1.6 Hz, 1H, amidine), 5.12 (mc, 1H, CH), 2.20 (mc,
2H, a-CH2), 1.83 (mc, 2H, a-CH2), 1.24 (mc, 16H, 8CH2), 0.80 (t, J=
6.7 Hz, 6H, 2CH3) ppm. 13C NMR (CDCl3): d=158.3 (3C=O), 144.5 (C=
N), 133.0 (C-amidine), 132.0, 130.8, 127.6, 126.3, 125.4, 125.3, 124.6 (10C-
naphthalene), 116.3 (C-amidine), 55.2 (CH), 32.3, 31.7, 29.7, 29.6, 29.3,
29.1, 29.0, 26.9, 22.7, 22.5 (10CH2), 14.1 (CH3), 14.0 (CH3) ppm. UV
(CHCl3):
lmax
(e)=436.4
(9960),
377.8
(8750),
360.0
(8500 dm3 molꢀ1 cmꢀ1) nm. Fluorescence (CHCl3): lmax =551 nm. Solid-
state fluorescence: lmax =571 nm. Fluorescence quantum yield (CHCl3,
E=0.0193 cmꢀ1, lexcit =375 nm, reference: perylene-3,4,9,10-tetracarbox-
ylic tetramethyl ester with F=1.0[41])=0.06. MS (70 eV): m/z (%) 472
(28) [M++1], 471 (88) [M+], 386 (5) [M+ꢀC6H13], 302 (10) [M+
ꢀC12H25], 290 (100) [M+ꢀC13H25], 272 (17), 244 (6), 218 (3). Elemental
analysis calcd (%) for C29H33N3O3 (471.6): C 73.86, H 7.05, N 8.91;
found: C 74.10, H 6.96, N 8.90.
(m), 754 (w) cmꢀ1 1H NMR (CDCl3): d=8.90 (d, J=7.7 Hz, 1H, naph-
.
thalene), 8.79 (d, J=7.7 Hz, 1H, naphthalene), 8.75 (s, 2H, naphthalene),
7.93 (d, J=1.5 Hz, 1H, amidine), 7.44 (d, J=1.6 Hz, 1H, amidine), 4.36
(mc, 1H, CH), 4.28 (d, J=3.5 Hz, 2H, CH2), 1.35 (d, J=6.2 Hz, 3H,
CH3) ppm. UV (CHCl3): lmax (e)=439.6 (7350), 377.5 (6540), 360.1
(6000 dm3 molꢀ1 cmꢀ1) nm. Fluorescence (CHCl3): lmax =556 nm. Solid-
state fluorescence: lmax =575 nm. MS (70 eV): m/z (%) 348 (4) [M++1],
347 (16) [M+], 304 (21) [M++1ꢀC2H4O], 303 (100) [M+ꢀC2H4O], 290
(49) [M+ꢀC3H5O], 275 (15), 272 (11), 259 (8), 246 (8), 219 (9). Elemental
analysis calcd (%) for C19H13N3O4 (347.3): C 65.70, H 3.77, N 12.10;
found: C 65.50, H 3.69, N 12.10.
2-Cyclohexylbenzo[lmn]imidazolo[1,2-j][3,8]phenanthroline-1,3,6-trione
(5d): Naphthalene-1,8:4,5-tetracarboxylic bisanhydride (2, 1.4 g,
5.2 mmol), 1,2-diaminoethane (470 mg, 7.8 mmol) and aminocyclohexane
(870 mg, 7.8 mmol) in DMF (70 mL) were allowed to react (4 h) and the
product purified as described above for 5a, method 2. Yield 225 mg
(12%), fine needles from chloroform, m.p. >3508C. Rf (silica gel,
CHCl3/acetone 5:1)=0.56. IR (KBr): n˜ =3430 (m, br), 3155 (w), 2928
(m), 2854 (w), 1705 (s), 1667 (s), 1618 (w), 1580 (w), 1552 (w), 1509 (w),
1454 (w), 1438 (w), 1411 (m), 1341 (s), 1281 (s), 1242 (m), 1188 (w), 1108
2-(4-tert-Butylphenyl)benzo[lmn]imidazolo[1,2-j][3,8]phenanthroline-
1,3,6-trione
(5r)
and
N,N’-bis(4-tert-butylphenyl)-1,2,3,4-
tetrahydronaphtho[2,3-b]pyrazine-5,6:9,10-bis(dicarboximide) (6r): 2,7-
Bis(4-tert-butylphenyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-tetrone (1r,
530 mg, 1.0 mmol) was refluxed in DMF (10 mL, bath 1608C) and treated
with 1,2-diaminoethane (1.2 g, 20 mmol). The mixture was cooled,
Chem. Eur. J. 2006, 12, 2815 – 2824
ꢀ 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemeurj.org
2821

H. Langhals and H. Jaschke
poured into a mixture ofwater (40 mL) and 2 n HCl (20 mL), stirred for
1 h, allowed to stand for 16 h, collected by vacuum filtration (D4 glass
filter), dried in air (1008C) and purified by column chromatography
(silica gel, CHCl3/acetone 5:1). The first yellow, strongly fluorescent frac-
tion of 6r was collected and purified by column chromatography (silica
gel, chloroform) and the second fraction of 5r was collected and also pu-
rified by column chromatography (silica gel, CHCl3/acetone 15:1).
lexcit =455 nm, reference: perylene-3,4,9,10-tetracarboxylic tetramethyl
ester with F=1.0[41])=0.42. MS (70 eV): m/z (%) 699 (14) [M++1], 698
(29) [M+], 656 (6), 642 (44), 641 (100) [M+ꢀC(CH3)3], 585 (13) [M+ꢀ2”
C(CH3)3], 571 (3), 434 (1), 313 (2). Elemental analysis calcd (%) for
C44H50N4O4 (698.9): C 75.54, H 7.21, N 8.02; found: C 75.01, H 7.15, N
7.85.
5s: Yield 18 mg (4%), m.p. >3508C. Rf (silica gel, CHCl3/acetone 5:1)=
0.68. IR (KBr): n˜ =3430 (m, br), 2962 (m), 2868 (w), 1715 (s), 1676 (s),
1582 (w), 1552 (w), 1507 (w), 1481 (w), 1406 (m), 1345 (s), 1280 (s), 1245
(m), 1191 (w), 1067 (w), 977 (w), 824 (w), 768 (m), 749 (m), 720
6r: Yield 62 mg (11%), m.p. >3508C. Rf (silica gel, CHCl3/acetone
5:1)=0.88. IR (KBr): n˜ =3436 (m, br), 3248 (w), 2961 (m), 2927 (m),
2869 (w), 1690 (s), 1636 (s), 1601 (m), 1549 (s), 1496 (m), 1438 (w), 1394
(m), 1364 (w), 1340 (m), 1284 (w), 1210 (m), 1040 (w), 864 (w), 834 (w),
1
(w) cmꢀ1. H NMR (400 MHz, CDC13): d=8.94 (d, J=7.7 Hz, 1H, naph-
783 (w), 717 (w) cmꢀ1
.
1H NMR (CDC13): d=10.58 (s, 2H, 2NH), 8.42
thalene), 8.84 (d, J=7.5 Hz, 1H, naphthalene), 8.80 (s, 2H, naphthalene),
7.96 (d, J=1.7 Hz, 1H, amidine), 7.58 (d, J=8.6 Hz, 2H, phenyl), 7.47
(d, J=8.6 Hz, 1H, phenyl), 7.46 (d, J=1.4 Hz, 1H, amidine), 7.00 (d, J=
2.2 Hz, 1H, phenyl), 1.31 (s, 9H, 3CH3), 1.27 (s, 9H, 3CH3) ppm. 13C
NMR (CDC13): d=163.9 (C=O), 163.8 (C=O), 158.3 (C=O), 150.3 (C-
Phenyl), 144.5 (C=N), 143.8, 133.2 (C-amidine), 132.5, 132.1, 132.0, 131.0,
128.9, 128.6, 127.9, 127.6, 126.8, 126.6, 126.0, 125.4, 124.9, 124.0, (10C-
naphthalene and 5C-phenyl), 116.4 (C-amidine), 35.6 (C(CH3)3), 34.3 (C-
(CH3)3), 31.7 (3CH3), 31.2 (3CH3) ppm. UV/Vis (CHC13): lmax (e)=437.6
(8010), 376.5 (8890), 359.0 (8290 dm3 molꢀ1 cmꢀ1) nm. Fluorescence
(CHC13): lmax =553 nm. Solid-state fluorescence: lmax =573 nm. MS
(70 eV): m/z (%) 477 (2) [M+], 462 (7) [M+ꢀCH3], 421 (25) [M++1ꢀC-
(CH3)3], 420 (100) [M+ꢀC(CH3)3], 404 (8), 388 (4), 272 (2), 190 (3).
HRMS (70 eV) for C30H27N3O3: calcd 477.2053; found: 477.2066.
(s, 2H, naphthalene), 7.59 (d, J=8.7 Hz, 4H, phenyl), 7.25 (d, J=9.1 Hz,
4H, phenyl), 3.73 (s, 4H, 2CH2), 1.39 (s, 18H, 2C(CH3)3) ppm. 13C NMR
(CDCl3): d=167.0 (2C=O), 163.8 (2C=O), 151.6 (2C-phenyl), 144.3 (2C-
naphthalene), 132.5 (2C-naphthalene), 127.8, 126.5, 125.3 (2C-naphtha-
lene), 123.2 (2C-phenyl), 38.2 (2CH2), 34.8 (2C(CH3)3), 31.4
(6CH3) ppm. UV (CHCl3): lmax (e)=488.9 (32680), 458.0 (19790), 432.5
(17670), 413.0 (12930 dm3 molꢀ1 cmꢀ1) nm. Fluorescence (CHCl3): lmax
(Irel)=500 (1), 526 (0.65) nm. MS (70 eV): m/z (%) 587 (42) [M++1], 586
(100) [M+], 571 (21) [M+ꢀCH3], 437 (15) [M+ꢀCH3-C10H14], 377 (3),
278 (6). Elemental analysis calcd (%) for C36H34N4O4 (586.7): C 73.70, H
5.84, N 9.55; found: C 73.63, H 5.88, N 9.15.
5r: Yield 45 mg (11%), m.p. >3508C. Rf (silica gel, CHCl3/acetone
5:1)=0.65. IR (KBr): n˜ =3435 (m, br), 2924 (s), 2852 (m), 1712 (s), 1664
(s), 1582 (w), 1552 (w), 1506 (w), 1464 (w), 1407 (m), 1382 (w), 1352 (m),
1281 (m), 1241 (m), 1195 (m), 1130 (w), 1066 (w), 976 (w), 884 (w), 832
2-(2,5-Dimethylphenyl)benzo[lmn]imidazolo[1,2-j][3,8]phenanthroline-
1,3,6-trione (5o) and N,N’-bis(2,5-dimethylphenyl)-1,2,3,4-tetrahydro-
naphtho[2,3-b]pyrazine-5,6:9,10-bis(dicarboximide) (6o): 2,7-Bis(2,3-
(w), 766 (m), 748 (m), 720 (w) cmꢀ1 1H NMR (400 MHz, CDC13): d=
.
8.92 (d, J=7.6 Hz, 1H, naphthalene), 8.82 (d, J=7.9 Hz, 1H, naphtha-
lene), 8.78 (s, 2H, naphthalene), 7.95 (d, J=1.7 Hz, 1H, amidine), 7.57
(d, J=7.5 Hz, 2H, phenyl), 7.45 (d, J=1.5 Hz, 1H, amidine), 7.24 (d, J=
8.3 Hz, 2H, phenyl), 1.38 (s, 9H, 3CH3) ppm. 13C NMR (CDC13): d=
163.2 (C=O), 163.0 (C=O), 158.2 (C=O), 151.9 (C-phenyl), 144.5 (C=N),
133.2 (C-amidine), 132.4, 132.1, 131.8, 130.9, 128.5, 127.9, 127.8, 126.8,
126.5, 125.9, 125.4, 124.8, 123.9, (10C-naphthalene and 5C-phenyl), 116.4
(C-amidine), 34.8 (C(CH3)3), 31.3 (3CH3) ppm. UV/Vis (CHC13): lmax
(e)=437.1 (8620), 375.4 (7680), 357.7 (7220 dm3 molꢀ1 cmꢀ1) nm. Fluores-
cence (CHC13): lmax =553 nm. Solid-state fluorescence: lmax =573 nm.
MS (70 eV): m/z (%) 422 (13) [M++1], 421 (43) [M+], 407 (29) [M+
+1ꢀCH3], 406 (100) [M+ꢀCH3], 388 (4), 272 (24), 244 (10), 203 (6), 189
(13). Elemental analysis calcd (%) for C26H19N3O3 (421.5): 74.10, H 4.54,
N 9.97; found: 74.18, H 4.50, N 9.94.
dimethylphenyl)benzo[lmn][3,8]phenanthroline-1,3,6,8-tetrone
(1o,
470 mg, 1.0 mmol), diaminoethane (1.2 g, 20 mmol) and N,N’-dimethyl-
formamide (10 mL) were allowed to react as described above for 2-(4-
tert-butylphenyl)benzo[lmn]imidazolo[1,2-j][3,8]phenanthroline-1,3,6-
trione (5r).
6o: Yield 37 mg (7%), m.p. >3508C. Rf (silica gel, CHCl3/acetone
15:1)=0.23. IR (KBr): n˜ =3436 (m, br), 3245 (w), 2923 (w), 2867 (w),
1689 (s), 1635 (s), 1601 (m), 1548 (s), 1496 (s), 1461 (w), 1438 (w), 1394
(m) , 1363 (w), 1339 (m), 1282 (m), 1258 (w), 1215 (m), 1164 (w), 1045
(w), 811 (w), 786 (m) cmꢀ1 1H NMR (300 MHz, CDC13): d=10.57 (s,
.
2H, 2NH), 8.41 (s, 2H, naphthalene), 7.29 (d, J=7.8 Hz, 2H, phenyl),
7.20 (d, J=7.8 Hz, 2H, phenyl), 7.02 (d, J=3.5 Hz, 2H, phenyl), 3.71 (s,
4H, 2CH2), 2.37 (s, 6H, 2CH3), 2.12 (s, 6H, 2CH3) ppm. 13C NMR
(CDCl3): d=166.6 (2C=O), 163.3 (2C=O), 144.3 (2C-phenyl), 137.0,
134.3, 132.6, 132.5, 130.9, 130.8, 130.0, 128.8, 128.7, 125.3, 123.4, 123.1
(10C-phenyl and 8C-naphthalene), 98.1 (2C-naphthalene), 38.2 (2CH2),
20.9 (2CH3), 17.1 (2CH3) ppm. UV/Vis (CHC13): lmax (e)=488.8
(31170), 458.0 (19780), 431.5 (17640), 413.3 (12560), 383.3 (sh)
(7110 dm3 molꢀ1 cmꢀ1) nm. Fluorescence (CHC13): lmax (Irel)=498 nm (1),
527 (0.52), 567 (sh) (0.1) nm. MS (70 eV): m/z (%) 531 (36) [M++1], 530
(100) [M+], 514 (25), 513 (71), 409 (4), 338 (4), 265 (6), 105 (11). Ele-
mental analysis calcd (%) for C32H26N4O4 (530.6): C 72.30, H 4.94, N
10.54; found: C 71.97, H 5.15, N 10.40.
2-(2,5-Di-tert-butylphenyl)benzo[lmn]imidazolo[1,2-j]-
[3,8]phenanthroline-1,3,6-trione (5s) and N,N’-bis(2,5-di-tert-butylphen-
yl)-1,2,3,4-tetrahydronaphtho[2,3-b]pyrazine-5,6:9,10-bis(dicarboximide)
(6s):
2,7-Bis(2,5-di-tert-butylphenyl)benzo[lmn][3,8]phenanthroline-
1,3,6,8-tetrone (1s, 480 mg, 1.0 mmol), diaminoethane (1.2 g, 20 mmol)
and N,N’-dimethylformamide (10 mL) were allowed to react as described
above for 2-(4-tert-butylphenyl)benzo[lmn]imidazolo[1,2-j][3,8]phen-
anthroline-1,3,6-trione (5r).
6s: Yield 22 mg (3%), m.p. >3508C. Rf (silica gel, CHCl3)=0.24. IR
(KBr): n˜ =3435 (m, br), 3248 (w), 2963 (m), 2870 (m), 1690 (s), 1636 (s),
1602 (m), 1580 (w), 1547 (s), 1497 (m), 1437 (w), 1396 (m) , 1363 (w),
1318 (w), 1253 (m), 1126 (w), 1042 (w), 828 (w), 791 (w), 765 (w), 750
(w) cmꢀl. 1H NMR (300 MHz, CDC13): d=10.61 (s, 2H, 2NH), 8.42 (d,
J=3.1 Hz, 2H, naphthalene), 7.60 (d, J=0.9 Hz, 1H, phenyl), 7.57 (d, J=
0.9 Hz, 1H, phenyl), 7.46 (dd, J3 =2.5 Hz, J4 =1.3 Hz, 1H, phenyl), 7.44
(dd, J3 =2.5 Hz, J4 =1.3 Hz, 1H, phenyl), 6.99 (d, J=2.2 Hz, 1H, phenyl),
6.93 (d, J=2.2 Hz, 1H, phenyl), 3.72 (brs, 4H, 2CH2), 1.32 (s, 9H, C-
(CH3)3), 1.30 (s, 9H, C(CH3)3), 1.27 (s, 9H, C(CH3)3), 1.26 (s, 9H, C-
(CH3)3) ppm. 13C NMR (CDC13): d=167.7 (2C=O), 164.5 (2C=O), 150.1
(2C-phenyl), 144.3 (2C-phenyl), 143.7 (2C-phenyl), 132.7 (2C-phenyl),
128.2 (2C-phenyl), 127.6 (2C-phenyl), 126.2, 125.3, 123.4, 123.3, 123.2,
(10C-naphthalene), 38.2 (2CH2), 35.6 (2C(CH3)3), 34.2 (2C(CH3)3), 31.8
(3CH3), 31.7 (3CH3), 31.3 (3CH3), 31.2 (3CH3) ppm. UV/Vis (CHC13):
lmax (e)=488.3 (32580), 457.7 (19400) 432.1 (17090), 412.6
(12390 dm3 molꢀ1 cmꢀ1) nm. Fluorescence (CHCl3): lmax (Irel)=500 (1),
5o: Yield 28 mg (7%), m.p. >3508C. Rf (silica gel, CHCl3/acetone 5:1)=
0.49. IR (KBr): n˜ =3431 (m, br), 2924 (m), 2855 (w), 1715 (s), 1677 (s),
1581 (m), 1552 (w), 1508 (m), 1438 (m), 1407 (w), 1380 (w), 1343 (s),
1319 (w), 1282 (m), 1247 (s), 1194 (w), 1146 (w), 978 (w), 812 (w), 767
(m), 756 (m) cmꢀ1 1H NMR (400 MHz, CDC13): d=8.94 (d, J=7.5 Hz,
.
1H, naphthalene), 8.83 (d, J=7.5 Hz, 1H, naphthalene), 8.79 (s, 2H,
naphthalene), 7.96 (d, J=1.5 Hz, 1H, amidine), 7.46 (d, J=1.5 Hz, 1H,
amidine), 7.29 (d, J=7.9 Hz, 1H, phenyl), 7.23 (d, J=7.9 Hz, 1H,
phenyl), 7.02 (d, J=2.5 Hz, 1H, phenyl), 2.37 (s, 3H, CH3), 2.15 (s, 3H,
CH3) ppm. 13C NMR (CDC13): d=162.7 (C=O), 162.5 (C=O), 158.2 (C=
O), 144.5 (C=N), 137.0, 133.6 (C-amidine), 133.2, 132.5, 132.4, 132.1,
131.0, 130.9, 130.3, 128.8, 128.4, 128.0, 126.8, 126.0, 125.4, 124.8, 123.7,
(10C-naphthalene and 6C-phenyl), 116.4 (C-amidine), 20.9 (CH3), 17.2
(CH3). UV/Vis (CHC13): lmax (e)=437.1 (8250), 376.4 (9210), 358.1
(8570), 437.6 (8010), 376.5 (8890), 359.0 (8290 dm3 molꢀ1 cmꢀ1) nm. Fluo-
rescence (CHC13): lmax =555 nm. Solid-state fluorescence: lmax =571 nm.
MS (70 eV): m/z (%) 394 (13) [M++1], 393 (51) [M+], 378 (25) [M+
526 (0.65) nm. Fluorescence quantum yield (CHCl3, E=0.0191 cmꢀ1
,
2822
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ꢀ 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Eur. J. 2006, 12, 2815 – 2824

Naphthalene Amidine Imide Dyes
FULL PAPER
+1ꢀCH3], 377 (27) [M+ꢀCH3], 376 (100) [M+ꢀOH], 361 (16) [M+
ꢀOHꢀCH3], 348 (7), 333 (5), 282 (4), 244 (4), 222 (4). Elemental analysis
calcd (%) for C24H15N3O3 (393.4): C 73.19, H 3.84, N 10.67; found: C
72.15, H 3.98, N 10.15.
NMR (CDC13): d=167.0 (C=O), 158.5 (C=O), 151.4 (C-phenyl), 144.8
(C=N), 136.1 (C-amidine), 132.0, 131.3, 126.7, 126.6, 125.8, 125.7, 125.5,
125.3, 124.8, 123.4, 106.9 (10C-naphthalene and 5C-phenyl), 116.6 (C-
amidine), 34.8 (C(CH3)3), 31.3 (3CH3) ppm. UV/Vis (CHC13): lmax (e)=
428.7
(sh)
(12800),
413.3
(13870),
364.8
(8650),
258.0
N,N’-Bis(1-methylpropyl)-1,2,3,4-tetrahydronaphtho[2,3-b]pyrazine-
5,6:9,10-bis(dicarboximide) (6a): 2,7-Bis(2,3-dimethylphenyl)benzo[lmn]-
[3,8]phenanthroline-1,3,6,8-tetrone (1a, 430 mg, 1.0 mmol), diamino-
ethane (1.2 g, 20 mmol) and N,N’-dimethylformamide (10 mL) were al-
lowed to react as described above for 2-(4-tert-butylphenyl)benzo-
[lmn]imidazolo[1,2-j][3,8]phenanthroline-1,3,6-trione (5r). The second,
strongly yellow fluorescent fraction was collected and purified by two fur-
ther column-chromatographic separations (silical gel, CHCl3/acetone 15:1
and silica gel, CHCl3). Yield 4 mg (1%), m.p. 2178C. Rf (silica gel,
CHCl3/acetone 15:1)=0.33. IR (KBr): n˜ =3435 (m, br), 3248 (w), 2963
(m), 2870 (m), 1690 (s), 1636 (s), 1602 (m), 1580 (w), 1547 (s), 1497 (m),
1437 (w), 1396 (m), 1363 (w), 1318 (w), 1253 (m), 1126 (w), 1042 (w), 828
(32660 dm3 molꢀ1 cmꢀ1) nm. Fluorescence (CHC13): lmax =544 nm. Solid-
state fluorescence: lmax =575 nm. MS (70 eV): m/z (%) 394 (19) [M++1],
393 (68) [M+], 379 (23) [M++1ꢀCH3], 378 (100) [M+ꢀCH3], 360 (3),
350 (7) [M+ꢀCH3ꢀCO], 338 (4), 337 (4), 189 (5), 175 (8). HRMS
(70 eV) for C25H19N3O2: calcd 393.1464; found: 393.1471. Elemental anal-
ysis calcd (%) for C25H19N3O2 (393.4): C 76.25, H 4.87, N 10.68; found: C
74.54, H 4.73, N 10.35.
(w), 791 (w), 765 (w), 750 (w) cmꢀl 1H NMR (400 MHz, CDC13): d=
.
Acknowledgements
10.63 (s, 2H, 2NH), 8.30 (s, 2H, naphthalene), 5.22 (mc, 2H, 2CH), 3.76
(s, 4H, 2CH2), 2.19 (mc, 2H, 2CH2), 1.93 (mc, 2H, 2CH2), 1.55 (d, J=
6.9 Hz, 6H, 2CH3), 0.87 (d, J=7.5 Hz, 6H, 2CH3) ppm. 13C NMR
(CDC13): d=167.3 (2C=O), 164.5 (2C=O), 144.0, 124.8, 122.6, 98.2
(10C-naphthalene), 51.0 (2CH), 38.3 (2CH2), 26.5 (2CH2), 18.0 (CH3),
11.5 (CH3) ppm. UV/Vis (CHC13): lmax (Erel)=488.9 (1), 458.0 (0.63),
432.5 (0.55), 413.0 (0.41) nm. Fluorescence (CHC13): lmax (Irel)=500 (1),
526 (0.63) nm. MS (70 eV): m/z (%) 435 (27) [M++1], 434 (100) [M+],
418 (12), 404 (18), 395 (7), 322 (92) [M+ꢀC8H16], 320 (61), 274 (11), 249
(8). HRMS (70 eV) for C24H26N4O4: calcd 434.1954; found: 434.1924.
This work was supported by the Deutsche Forschungsgemeinschaft and
the Fonds der Chemischen Industrie. We thank Prof. Dr. H. Nçth for car-
rying out X-ray crystallographic analyses.
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7a:
2-(1-Methylpropyl)benzo[lmn]imidazolo[1,2-j][3,8]phenanthroline-
1,3,6-trione (5a, 60 mg, 0.17 mmol) was dispersed in a mixture ofmetha-
nol (3 mL) and DMSO (3 mL), treated with 85% solid KOH (490 mg,
7.5 mmol), refluxed for 3 h (colour change to red), cooled, poured into
conc. HCl, stirred for 1 h, left to stand for 16 h, collected by vacuum fil-
tration (D4 glass filter, orange solid) and purified by column chromatog-
raphy (silica gel, CHCl3/acetone 15:1). Yield 6 mg (12%), m.p. 2488C. Rf
(silica gel, CHCl3/acetone 15:1)=0.48. IR (KBr): n˜ =3431 (m, br), 2971
(w), 2934 (w), 2878 (w), 1706 (s), 1657 (m), 1623 (w), 1585 (w), 1556 (w),
1495 (s), 1469 (w), 1446 (w), 1418 (m), 1390 (w), 1352 (m), 1270 (m),
1
1179 (w), 1065 (w), 1029 (w), 953 (w), 755 (m) cmꢀl. H NMR (400 MHz,
CDC13): d=8.47 (d, J=7.6 Hz, 1H, naphthalene), 8.46 (d, J=7.5 Hz,
1H, naphthalene), 8.10 (d, J=7.3 Hz, 1H, naphthalene), 7.87 (d, J=
1.5 Hz, 1H, amidine), 7.31 (d, J=1.5 Hz, 1H, amidine), 7.12 (d, J=
7.6 Hz, 1H, naphthalene), 4.52 (mc, 1H, CH), 2.01 (mc, 1H, CH2), 1.88
(mc, 1H, CH2), 1.55 (d, J=6.9 Hz, 3H, CH3), 0.93 (t, J=7.4 Hz, 3H,
CH3) ppm. 13C NMR (CDC13): d=167.8 (C=O), 158.6 (C=O), 146.1,
144.9 (C=N), 136.0 (C-amidine), 131.9, 126.0, 125.4, 125.3, 107.1 (10C-
naphthaliene), 116.8 (C-amidine), 50.3 (CH), 27.5 (CH2), 18.8 (CH3), 11.2
(CH3) ppm. UV/Vis (CHC13): lmax (e)=424.1 (15910), 408.5 (sh)
(14710), 362.4 (7830), 346.8 (sh) (3370), 255.6 (32840 dm3 molꢀ1 cmA1) nm.
Fluorescence (CHC13): lmax =536 nm. Solid-state fluorescence: lmax
570 nm. Fluorescence quantum yield (CHCl3, E=0.0198 cmꢀ1
lexcit
=
,
=
405 nm, reference: perylene-3,4,9,10-tetracarboxylic tetramethyl ester
with F=1.0[41])=0.12. MS (70 eV): m/z (%) 318 (11) [M++1], 317 (48)
[M+], 302 (6) [M+ꢀCH3], 288 (100) [M+ꢀC2H5], 261 (15) [M+ꢀC4H8],
219 (4), 191 (3). HRMS (70 eV) for C19H15N3O2: calcd 317.1164; found:
317.1167.
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Rf (silica gel, CHCl3/acetone 15:1)=0.18. IR (KBr): n˜ =3431 (m, br),
2961 (m), 2925 (m), 2854 (w), 1732 (m), 1709 (s), 1656 (m), 1628 (w),
1518 (m), 1495 (s), 1468 (w), 1447 (w), 1415 (m), 1365 (m), 1271 (m),
1248 (w), 1235 (w), 1175 (w), 1031 (w), 967 (w), 912 (w), 834 (w), 754
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1
(m) cmꢀl. H NMR (400 MHz, CDC13): d=8.52 (d, J=7.4 Hz, 1H, naph-
thalene), 8.48 (d, J=7.7 Hz, 1H, naphthalene), 8.21 (d, J=7.4 Hz, 1H,
naphthalene), 7.89 (d, J=1.7 Hz, 1H, amidine), 7.58 (d, J=8.8 Hz, 2H,
phenyl), 7.45 (d, J=8.8 Hz, 2H, phenyl), 7.33 (d, J=1.4 Hz, 1H, ami-
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Chem. Eur. J. 2006, 12, 2815 – 2824
ꢀ 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Received: July 27, 2005
Published online: January 19, 2006
2824
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ꢀ 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Eur. J. 2006, 12, 2815 – 2824