Post on 21-Mar-2020
Supporting Information
© Wiley-VCH 2008
69451 Weinheim, Germany
S1
Zipper Assembly of Vectorial Rigid-Rod -Stack Architectures with Red
and Blue Naphthalenediimides: Toward Supramolecular Cascade n/p-
Heterojunctions
Adam L. Sisson,† Naomi Sakai,
† Natalie Banerji,
‡ Alexandre Fürstenberg,
‡ Eric Vauthey,*
,‡ and Stefan
Matile*,†
†Department of Organic Chemistry and
‡Department of Physical Chemistry, University of Geneva,
Geneva, Switzerland. *To whom correspondence should be addressed. E-mail:
eric.vauthey@chiphy.unige.ch, stefan.matile@chiorg.unige.ch
Supplementary Information
Table of Content
1. Materials and methods S2
2. Supplementary text S4
2.1 Synthesis of cationic N,Cl-NDI octamer 2 and N,Cl-NDI monomer 2a S4
2.2 Electrochemistry S8
2.3 Steady-state photophysics S9
2.4 Fluorescence dynamics S10
2.5 Transient absorption spectroscopy S11
2.6 Zipper assembly on gold electrodes S12
3. Supplementary schemes and figures S14
4. Supplementary tables S22
5. Supplementary references S24
S2
1. Materials and methods
As in ref. [S1], Supplementary Information. Briefly, reagents for synthesis were purchased
from Fluka, amino acid derivatives from Novabiochem and Bachem, HATU from Applied
Biosystems, buffers, and salts from Sigma or Fluka-Aldrich. All reactions were performed under N2
or argon atmosphere. Unless stated otherwise, column chromatography was carried out on silica gel
60 (Fluka, 40-63 m). Analytical (TLC) and preparative thin layer chromatography (PTLC) were
performed in silica gel 60 (Fluka, 0.2 mm) and silica gel GF (Analtech, 1000 m), respectively.
HPLC was performed using either Jasco HPLC system (PU-980, UV-970, FP-920) or an Agilent
1100 series apparatus with a photo diode array detector. [ ]20
D values were recorded on a Jasco P-
1030 Polarimeter, melting points (m.p.) on a heating table from Reichert (Austria), IR spectra were
recorded on a Perkin Elmer Spectrum One FT-IR spectrometer (ATR, Golden Gate, unless stated)
and are reported as wavenumbers in cm-1
with band intensities indicated as s (strong), m
(medium), w (weak). ESI-MS were performed on a Finnigan MAT SSQ 7000 instrument or a ESI
API 150EX, HR ESI-MS on a Sciex QSTAR Pulsar mass spectrometer, MALDI-TOF on a Axima
CFR+ (Shimadzu).
1H and
13C spectra were recorded (as indicated) either on a Bruker 300 MHz,
400 MHz or 500 MHz spectrometer and are reported as chemical shifts ( ) in ppm relative to TMS
( = 0). Spin multiplicities are reported as a singlet (s), doublet (d), triplet (t), quartet (q) and quintet
(quint) with coupling constants (J) given in Hz, or multiplet (m). Broad peaks are marked as br. 1H
and 13
C resonances were assigned with the aid of additional information from 1D & 2D NMR
spectra (H,H-COSY, DEPT 135, HSQC and HMBC). UV-Vis spectra were measured either on a
Varian Cary 1 Bio spectrophotometer (solution samples) or Agilent 8453 spectrophotometer (solid
samples) and are reported as maximal absorption wavelength in nm (extinction coefficient in
mM-1
cm-1
). Electrochemical measurements were done on an Electrochemical Analyzer with
S3
Picoamp booster and Faraday cage (CH Instruments 660C). Eppendorf Minispin centrifuge was
used for the precipitation of gold nano-particles. Photocurrents measurements were performed
using a 150 W Xe lamp (Hamamatsu), a monochromator (Instrument SA, H-10 1200UV), and an
Electrochemical Analyzer (CH Instruments 660C). The power of light was measured using a
portable laser power meter (Spectra Physics Model 407A).
Abbreviations. ACN: acetonitrile; Alloc: Allyloxycarbonyl; Au-nps: gold nanoparticles; Boc:
t-Butoxycarbonyl; calcd: Calculated; CS: charge-separated; DMA: N,N-Dimethylaniline; DMF:
N,N-Dimethylformamide; en: Ethylenediamine; ESA: excited state absorption; Fc: Ferrocene; FF:
Fill factor; FWHM: full width at half maximum; Gla: Glycolic acid; Glu: L-Glutamic acid; HATU:
N-[(Dimethylamino)-1H-1,2,3 -triazolo[4,5-b]pyridin-1-ylmethylene]-N-methylmethanammonium
hexafluorophosphate N-oxide; HMB: hexamethylbenzene; HRMS: High resolution mass
spectrometry; Lys: L-Lysine; NDI: Naphthalenediimide; RPHPLC: Reverse phase high
performance liquid chromatography; rt: Room temperature; SE: stimulated emission; sh: Shoulder;
TCNE: Tetracyanoethylene; TCSPC: time-correlated single photon counting; TEA: Triethylamine;
TEOA: Triethanolamine; TFA: Trifluoroacetic acid; TFE: 2,2,2-Trifluoroethanol; Z:
(Benzyloxy)carbonyl.
S4
2. Supplementary text
2.1. Synthesis of cationic N,Cl-NDI octamer 2 and N,Cl-NDI monomer 2a
Alloc-en-[Cl,Cl-NDI]-Lys(Z)-NH2 5. This compound was prepared from 6 following
previously reported procedures.[S1]
Alloc-en-[N,Cl-NDI]-Lys(Z)-NH2 7. Cl,Cl-NDI 5 (170 mg, 0.234 mmol) was dissolved in
stirred isopropylamine (15 ml). After 5 min at rt, the red solution was evaporated to dryness under
reduced pressure. Purification by column chromatography (CH2Cl2/MeOH 98:2; Rf = 0.5 with
CH2Cl2/MeOH 94:6) gave 7 (170 mg, quantitative) as a red solid. [ ]20
D = - 14.5 (c = 1.00 in
MeOH/CH2Cl2 1:1); IR: 3331 (m), 2936 (m), 1668 (s), 1637 (s), 1583 (s), 1444 (s), 1259 (s), 1214
(s), 1142 (s), 992 (m), 915 (m), 790 (m), 733 (m); 1H NMR (400 MHz, CDCl3/CD3OD 6:1, N/N =
regioisomeric equivalents): 9.94/9.85, (d, 3J(H,H) = 7.6/7.2 Hz, 1H), 8.39/8.20 (s, 1H), 8.08/7.93
(s, 1H), 7.39 - 7.15 (m, 5H), 6.16 - 6.12/6.09 - 6.05 (m, 1H), 5.89 - 5.75 (m, 1H), 5.68 - 5.60/5.60 -
5.52 (m, 1H), 5.23 - 4.95 (m, 2H), 4.94/4.93 (s, 2H), 4.44 - 4.35 (m, 2H), 4.19 - 4.09 (m, 1H), 4.10 -
4.00 (m, 2H), 3.41 - 3.25 (m, 2H), 3.12 - 3.05 (m, 2H), 2.48 - 2.25 (m, 1H), 2.21 - 2.09 (m, 1H),
1.61 – 1.35 (m, 4H), 1.49 (br.s, 6H); 13
C NMR (125 MHz, CDCl3/CD3OD 6:1, N/N = regioisomeric
equivalents): 176.7/176.3 (s), 169.3/169.2 (s), 167.1 (s), 165.9/165.7 (s), 165.7 (s), 165.1 (s),
161.0/160.9 (s), 154.8/154.7 (s), 140.5 (s), 138.8/138.5 (s), 136.6 (d), 132.3 – 131.2 (d, 5x),
132.3/132.1 (s), 132.0/131.9 (s), 131.3/131.2 (s), 130.6 (d), 125.7/125.3 (d), 125.2/125.0 (d),
124.9/124.7 (d), 121.2 (t), 103.0/102.7 (s), 70.4 (t), 69.4 (t), 58.7/58.1 (d), 57.5 (d), 44.5/44.4 (t),
44.3 (t), 43.0/42.8 (t), 33.3 (t), 31.9/31.8 (t), 27.6 (t), 26.9 (q), 26.9 (q); MS (ESI, +ve): m/z (%)
769 (25 [M + Na]+), 748 (100 [M + H]
+), 730 (60 [M – OH]
+); HR-MS (ESI, +ve): Calcd for
S5
C37H41O9N6Cl+: 747.2559, Found: 747.2539.
H-en-[N,Cl-NDI]-Lys(Z)-NH2 8. To a solution of 7 (50 mg, 67 mol) in dry CH2Cl2 (5 ml)
were added p-nitrophenol (28 mg, 0.20 mmol) and tributyltin hydride (97 mg, 0.34 mmol) followed
by Pd(PPh3)2Cl2 (1 mg, 0.001 mmol). After stirring for 3 h at rt, the reaction mixture was dried
under reduced pressure and lipophilic impurities were removed by solid-liquid extraction with
heptane (5 5 ml). Further purification by column chromatography (CH2Cl2/MeOH 90:10 then
CH2Cl2/MeOH/TEA 90:10:1; Rf = 0.4 with CH2Cl2/MeOH/TEA 90:10:1) gave 8 (44 mg,
quantitative) as a red solid. [ ]20
D = - 12.8 (c = 1.00 in MeOH); 1H NMR (400 MHz, CDCl3, N/N =
regioisomeric equivalents): 10.08/10.00 (d, 3J(H,H) = 7.6/8.0 Hz, 1H), 8.66/8.64 (s, 1H),
8.35/8.32 (s, 1H), 7.35 - 7.28 (m, 5H), 5.75/5.69 (t, 3J(H,H) = 7.6/7.2 Hz, 1H), 5.05/5.04 (s, 2H),
4.82 (br.s, 1H), 4.32 - 4.25 (m, 2H), 4.30 - 4.15 (m, 1H), 3.25 - 3.15 (m, 2H), 3.12 - 3.06 (m, 2H),
2.41 - 2.29 (m, 2H), 1.80 - 1.51 (m, 4H), 1.50 (d, 3J(H,H) = 6.0 Hz, 6H); MS (ESI, +ve): m/z (%)
664 (80 [M + H]+), 646 (100 [M - OH]
+).
13,2
3,3
2,4
3,5
2,6
3,7
2,8
3-Octakis(Gla-OH)-p-octiphenyl 9. This compound was prepared from
Fast Blue B in overall nine steps following previously reported procedures.[S2]
13,2
3,3
2,4
3,5
2,6
3,7
2,8
3-Octakis(Gla-en-[N,Cl-NDI]-Lys(Z)-NH2)-p-octiphenyl 10. A solution
of 9 (4.5 mg, 0.0037 mmol), HATU (17 mg, 0.045 mmol) and 2,6,di-tert-butylpyridine (69 mg,
0.36 mmol) in dry DMF (1 ml) was stirred for 30 min at rt. Then a solution of 8 (30 mg, 0.045
mmol) and TEA (24 mg, 0.24 mmol) in dry DMF (2 ml) was added. After stirring for 16 h at rt, the
reaction mixture was evaporated to dryness azeotropically with toluene. A preliminary purification
by column chromatography (CH2Cl2/MeOH 85:15) was followed by two PTLCs (first
S6
CH2Cl2/MeOH 85:15, Rf = 0.5, then CH2Cl2/MeOH 94:6, Rf = 0.1) to give 10 (16 mg, 66%) as a red
solid. 1H NMR (400 MHz, CDCl3/CD3OD 1:1): 9.97 - 9.70 (m, 8H), 8.21- 7.84 (m, 16H), 7.45 -
6.95 (m, 24H), 6.81 - 6.78 (m, 2H), 7.25 - 7.15 (m, 40H), 5.61 - 5.39 (m, 8H), 4.97 - 4.81 (m, 16H),
4.49 - 4.21 (m, 16H), 4.21 - 3.79 (m, 24H), 3.57 - 3.30 (m, 16H), 3.10 - 2.96 (m, 16H), 2.30 - 1.90
(m, 16H), 1.59 - 1.37 (m, 16H), 1.35 – 1.11 (m, 64H).
13,2
3,3
2,4
3,5
2,6
3,7
2,8
3-Octakis(Gla-en-[N,Cl-NDI]-Lys-NH2)-p-octiphenyl, TFA salt 2. A
solution of 10 (2 mg, 0.3 µmol) in TFA (1 ml) was stirred for 3h at 50 °C. After this time, the red
solution was evaporated to dryness under reduced pressure. Impurities were removed by solid-
liquid extraction with heptane (3 2 ml), ether (3 2 ml) and CH2Cl2 (3 2 ml), leaving 2 (2 mg,
quantitative) as a red solid. 1H NMR (400 MHz, CD3OD): 8.41 - 7.72 (m, 16H), 7.56 - 6.72 (m,
26H), 5.78 - 5.30 (m, 8H), 4.60 - 4.25 (16H), 4.40 - 3.82 (m, 24H), 3.55 - 3.28 (m, 16H), 3.15 - 2.82
(m, 16H), 2.51 - 2.28 (m, 8H), 2.24 - 2.00 (m, 8H), 1.87 - 1.61 (m, 16H), 1.67 - 1.35 (m, 16H), 1.41
- 1.22 (m, 48H); MS (ESI, +ve): m/z (%) 1765 (10 [M + 3H]3+
), 1346 (25 [M + 4Na]4+
), 1324 (35
[M + 4H]4+
), 1077 (45 [M + H + 4Na]5+
), 1060 (70 [M + 5H]5+
), 898 (55 [M + 2H + 4Na]6+
), 883
(100 [M + 6H]6+
), 770 (40 [M + 3H + 4Na]7+
), 755 (60 [M + 7H]7+
).
Alloc-en-[N,Cl-NDI]-Lys-NH2, TFA salt 2a. A solution of 7 (30 mg, 0.040 mmol) in TFA (2
ml) was stirred for 3 h at 50 °C. After this time, the red solution was evaporated to dryness under
reduced pressure. Impurities were removed by solid-liquid extraction with petroleum ether (3 2
ml) leaving 2a (28 mg, quantitative) as a red solid. [ ]20
D = - 13.2 (c = 1 in MeOH); IR: 2970
(m), 2409 (m), 1667 (s), 1634 (s), 1441 (s), 1200 (s), 1174 (s), 1126 (s), 991 (m), 918 (m), 833 (m),
790 (m), 720 (m); 1H NMR (400 MHz, CD3OD, N/N = regioisomeric equivalents): 8.38/8.29 (s,
1H), 8.14 (s, 1H), 5.82 - 5.71 (m, 1H), 5.70/5.63 (t, 3J(H,H) = 7.6/7.2 Hz, 1H), 5.20 - 5.16 (m, 1H),
S7
5.09 - 5.05 (m, 1H), 4.38/4.37 (s, 2H), 4.29 – 4.23 (m, 1H), 4.18 - 4.05 (m, 2H), 3.37 - 3.28 (m,
2H), 3.07 - 2.98 (m, 2H), 2.55 - 2.46 (m, 1H), 2.31 - 2.18 (m, 1H), 1.91 - 1.72 (m, 2H), 1.69 - 1.52
(m, 2H), 1.59 - 1.50 (m, 6H); 13
C NMR (125 MHz, CD3OD, N/N = regioisomeric equivalents):
190.6 (s), 173.1/172.8 (s), 165.5/165.3 (s), 162.0 (s), 161.9 (s), 161.7/161.6 (s), 160.9/160.8 (s),
157.5 (s), 150.7/150.6 (s), 134.0 (d), 133.7 (d), 133.0/132.9 (d), 132.0/131.9 (s), 131.3/131.2 (s),
130.6 (d), 125.7/125.3 (d), 125.2/125.0 (d), 124.9/124.7 (d), 121.2 (t), 103.0/102.7 (s), 70.4 (t), 69.4
(t), 58.7/58.1 (d), 57.5 (d), 44.5/44.4 (t), 44.3 (t), 43.0/42.8 (t), 33.3 (t), 31.9/31.8 (t), 27.6 (t), 26.9
(q), 26.9 (q); MS (ESI, +ve): m/z (%) 635 (15 [M + Na]+), 613 (100 [M]
+), 596 (50 [M – OH]
+).
N,N-NDI Initiator 1. This compound was prepared following previously reported procedures
(Fig. S1).[S3]
Anionic N,N-NDI octamer 3. This compound was prepared following previously reported
procedures (Fig. S1).[S3]
Cationic N,N-NDI octamer 4. This compound was prepared following previously reported
procedures (Fig. S1).[S1]
N,N-NDI monomer 4a. This compound was prepared following previously reported
procedures (Table S1).[S1]
S8
2.2. Electrochemistry
Oxidation and reduction potential of 7 was determined by cyclic voltammetry vs Fc/Fc+ in
dichloromethane (Figure S2, scan rate 100 mV/s, supporting electrolyte: 100 mM Bu4NPF6,
working electrode: Pt disk, counter electrode: Pt wire, reference electrode: Ag/AgCl). Results are
shown in Table S1 in comparison with literature data for related NDIs 4b,[S4]
4c[S3]
and 2b,[S4]
13,2
3,3
2,4
3-p-quateranisole (11),
[S3] p-quaterphenyl (12) and p-octiphenyl (13).
[S5] HOMO and
LUMO energies were calculated from oxidation and reduction potentials using eq (S1)[S6]
EHOMO/LUMO = - 4.8 eV - E1/2 vs (Fc/Fc+) (S1)
The obtained bandgaps ELUMO – EHOMO were converted into absorption wavelength using eq
(S2)
calc (nm) = hc / (ELUMO – EHOMO) = 1240 / (ELUMO – EHOMO) (S2)
and compared to the measured values max (Table S1, Figure S3, ref. [S7]).
S9
2.3 Steady-state photophysics
The photophysics of rNDIs has been investigated in solution in methanol (MeOH) using steady-
state absorption and steady-state and time-resolved fluorescence techniques. Absorption spectra were
recorded on a Cary 50 spectrophotometer and fluorescence spectra on a Cary Eclipse fluorimeter in
a 1 cm quartz cell. Results are compared to those previously obtained with a bNDI derivative.
Monomer 2a and octamer 2 in MeOH display a single absorption band above 400 nm centered
around 530 nm (Figure S3, Figure 3b). The fluorescence spectrum (excitation at 460 nm, Figure S4)
of 2 and 2a peaks around 570 nm in MeOH. Fluorescence quantum yields, determined as
previously reported for bNDI derivation,[S1]
were low in protic solvents and with rNDI octamer 2
but high in aprotic solvents and with rNDI monomer 2a (Table S2).
The possibility of quenching of rNDI chromophores by the p-octiphenyl scaffolds via
photoinduced electron transfer was demonstrated by mixing 2a with hexamethylbenzene (HMB)
which has the same oxidation potential as the p-quateranisole 11. The fluorescence intensity
decreased markedly with increasing HMB concentration (Figure S5, Figure 2b). From the slope of
the linear regression and using the Stern-Volmer equation for collisional quenching,[S8] a quenching
rate constant of 4·109 s-1·M-1 is extracted, relatively close to the diffusion limit of ~2·1010 s-1·M-1 in
acetonitrile. This indirect evidence was further confirmed by mixing directly 2a with bianisole 14 (170
mM) or quateranisole 11 (29 mM) in acetonitrile: Figures S5 and 2b show that the fluorescence of
2a was efficiently quenched. On the other hand, the fluorescence of bNDI 4a was not altered by the
presence of 32 mM HMB, indicating that only rNDIs can undergo photoinduced charge separation
with the p-octiphenyl scaffold.
S10
2.4 Fluorescence dynamics
The fluorescence dynamics was recorded using the time-correlated single photon counting
(TCSPC) and the fluorescence up-conversion (400 nm excitation, 575 nm detection) techniques. For
TCSPC measurements, excitation was performed at 395 nm with a pulsed laser diode (Picoquant
model LDH-P-C-400B). The pulses had duration of about 65 ps and the average power was about
0.5 mW at 10 MHz. Fluorescence was collected at 90°, and passed through an analyzer set at the
magic angle with respect to the excitation polarization, and a 450 nm-cutoff filter located in front of
a photomultiplier tube (Hamamatsu, H5783-P-01). The detector output was connected to the input
of a TCSPC computer board module (Becker and Hickl, SPC-300-12). The full width at half
maximum (FWHM) of the instrument response was around 200 ps. Measurements were performed
in a 1 cm quartz cell. Data were reproduced by iterative reconvolution of a sum of exponentials to
the measured instrument response function.
The fluorescence up-conversion set-up uses the frequency-doubled output of a Kerr lens mode-
locked Ti:sapphire laser (Tsunami, Spectra-Physics) for excitation of the sample at 400 nm.[S9] The
output pulses centered at 800 nm had duration of 100 fs and repetition rate of 82 MHz.
Experiments were carried out in a 1 mm rotating cell. Fluorescence decays were analyzed by
iterative reconvolution of a sum of exponential functions with a Gaussian response function of 280
fs FWHM. Fluorescence decay kinetics demonstrated that photoinduced charge separation in 2
occurs to 95% within 170 ps (Table S3). A detailed discussion and analysis of the fluorescence
decay kinetics data will be published in a more specialized journal.
S11
2.5 Transient absorption spectroscopy
Transient absorption measurements were performed with 400 M solutions of rNDI monomer
2a in MeOH and with 50 M solutions of rNDI octamer 2 in MeOH in a 1 mm quartz cell.
Excitation at 530 nm was achieved with a home-built two-stage noncolinear optical parametric
amplifier, fed by the 800 nm output of a standard 1 kHz amplified Ti:Sapphire system (Spectra-
Physics). After recompression with a pair of prisms, the pulse duration was of the order of 100 fs.
The energy per pulse at the sample was around 3 µJ. Probing was achieved with a white light
continuum obtained by focussing 800 nm pulses in a H2O/D2O mixture. The probe beam was split
into a pumped signal beam and an un-pumped reference beam before the sample. The transmitted
signal and reference beams were detected by an ORIEL MultispecTM
125 spectrograph coupled to a
CCD detector (Entwicklungsbüro G. Stresing, Berlin). To improve the sensitivity, the pump light
was chopped at half the amplifier frequency, and the transmitted signal intensity was recorded shot
by shot. It was corrected for intensity fluctuations using the reference beam. The transient spectra
were averaged until the desired signal to noise ratio was achieved. The angle between the
polarization of the pump and probe beam was set to 54.7° (magic angle). Artefacts due to parasitic
light (pump light reaching the detectors, dispersed spontaneous fluorescence of the sample) were
subtracted from the transient spectra. All transient spectra were then corrected for the chirp of the
white light.
Data analysis of the transient spectra of 2 in MeOH is complicated by the complete overlap of
the S1 and CS state spectra. Additionally to this, early spectral dynamics due to vibrational and
solvent relaxation is also present. Nonetheless, without a detailed analysis already, it is possible to
see that the charge-separated state decays on a slower time scale (500 ps average time constant)
than with 4 (Figure 2d). A detailed discussion and analysis of the transient absorption data is to be
S12
published in a more specialized journal (global fit, subtraction and iterative deconvolution of
complex kinetics, etc).
2.6 Zipper assembly on gold electrodes
Gold electrodes. Gold electrodes were prepared as reported in ref [S3]: Gold-coated glass
slides (22 x 22 mm2) were purchased from Mivitec GmbH, Analytical -Systems (Germany).
Before use, the plates were cleaned using ‘piranha’ solution (H2SO4 / 30 % H2O2 3 / 1; 35 °C for 5
min).[S10]
Caution: piranha solution reacts violently with organic compounds. It should be handled
with extreme care. After the treatment with piranha solution, the plates were thoroughly rinsed with
water and EtOH, and used immediately.
Initiation. Zipper initiation was done as reported in ref [S3]: The cleaned gold plates were
immersed in the solution of the initiator 1 (~7 M) in a 1:1 mixture of TFE : 1 mM sodium
phosphate buffer (pH 7) for 3 days. The obtained Au-1 electrodes were tested for defects using
the standard procedure in which reduction-oxidation of K3Fe(CN)6 (2 mM in 1 M aqueous KNO3)
was measured by cyclic voltammetry using Au-1 as working electrode.[S3,S11]
The absence of redox
wave confirmed the absence of large uncovered areas on the Au electrode.
Blue multilayers. Au-1-4-3-4 was prepared as reported in ref [S3]: Coated gold electrodes
Au-1 were immersed in the solution of cationic bNDI octamer 4 (~10 M) in a 1 : 1 mixture of TFE
and 0.5 mM sodium phosphate, 0.5 M NaCl buffer (pH 7) for overnight. The plate was rinsed with
bidistilled water and EtOH, and the photocurrent of the resulting plate was recorded (see below).
Obtained two-layers coated plates Au-1-4 were similarly treated with anionic bNDI octamer 3 to
S13
give Au-1-4-3, which in turn was treated with cationic bNDI octamer 4 to give Au-1-4-3-4.
Mixed multilayers (Figs 3a and S7). Mixed multi-layers were built by using cationic rNDI
octamer 2 (~10 M in 1:1 TFE / 0.5 mM sodium phosphate, 0.5 M NaCl buffer, pH 7) in place of
cationic bNDI octamer 4 in the procedures described above.
Photocurrent measurements. Coated gold electrodes were used as a working electrode (Pt
wire as a counter electrode) in an aqueous solution of TEOA (50 mM) and Na2SO4 (0.1 M) and
irradiated with a Xe lamp through water to filter off IR component (area of irradiation ~0.8 cm2).
Changes in current upon on-off switching of irradiations (20 seconds each) were measured at +0.4 V
vs Ag/AgCl unless stated. The power of irradiation was ~1 W cm-2
. For each gold plate,
photocurrent obtained for Au-1 (0.5 to 1.1 A) was used as a standard (=1) and relative increase in
current was reported for the following multi-layers. For the I-V measurements, the electrolyte
solution was deaerated by bubbling N2.
Action spectra (Fig. 3b). Photocurrent densities were measured at open circuit potential in the
dark upon excitation by monochromatic light (power reaching to the sample 1.5 mW cm-2
) and
plotted against the irradiation wavelength.
S14
3. Supplementary schemes and figures
N
NO O
OO
NH2
O
NHAlloc
NHZ
Cl
Cl
O
OO O
OO
Cl
Cl
7: R = Alloc; R' = Z8: R = H; R' = Z2a: R = Alloc; R' = H
N
NO O
OO
NH2
O
NHR
NHR'
NH
Cl
O
O
O
O
O
O
O
O
HO
O
HO
O
HO
O
HO
O
OH
O
OH
O
OH
O
OH
O
6
5
N
NO O
OO
NH2
O
NHR
NHR'
Cl
HN
+
9
a) b)
c)
O
O
O
O
O
O
O
O
O
HN
10: R'' = Z2: R'' = H
e)
N N
O
OO
ONH2
O
NHR''
Cl
HN
O
HN
N N
O
OO
ONH2
O
NHR''
Cl
HNO
HN
N N
O
OO
ONH2
O
NHR''
Cl
HN
O
HN
N N
O
OO
ONH2
O
NHR''
Cl
HNO
NHNN
O
O O
OH2N
O
R''HN
Cl
NH
O
NHNN
O
O O
OH2N
O
R''HN
Cl
NHO
NH
NN
O
O O
OH2N
O
R''HN
Cl
NH
O
NH
NN
O
O O
OH2N
O
R''HN
Cl
NH
d)
f)
Scheme S1. a) see ref. [S1]; b) i-PrNH2 (quant); c) PdCl2(PPh3)4, Bu3SnH, p-nitrophenol
(quant); d) HATU, di-t-Bu-pyridine, TEA, DMF (66 %); e) TFA, CH2Cl2 (quant); f) TFA, CH2Cl2
(quant). Note, 10 and 2 contain both regioisomers (2,6- and 3,7-) of rNDIs.
S15
ONH
O
ONH
O
O
HN
OO
OO
O
S S
HN
HN
1
NN
O
O O
OH2N
O
OOC
HN
NH
NN
O
O O
OH2N
O
OOC
HN
NH
N N
O
OO
ONH2
O
COO
NH
HN
N N
O
OO
ONH2
O
COO
NH
HN
O
O
O
O
O
O
O
O
O
HN
N N
O
OO
ONH2
O
COO
NH
HN
O
HN
N N
O
OO
ONH2
O
COO
NH
HNO
HN
N N
O
OO
ONH2
O
COO
NH
HN
O
HN
N N
O
OO
ONH2
O
COO
NH
HNO
NHNN
O
O O
OH2N
O
OOC
HN
NH
O
NHNN
O
O O
OH2N
O
OOC
HN
NHO
NH
NN
O
O O
OH2N
O
OOC
HN
NH
O
NH
NN
O
O O
OH2N
O
OOC
HN
NH
3
O
O
O
O
O
O
O
O
O
HN
N N
O
OO
ONH2
O
NH3
NH
HN
O
HN
N N
O
OO
ONH2
O
H3N
NH
HNO
HN
N N
O
OO
ONH2
O
NH3
NH
HN
O
HN
N N
O
OO
ONH2
O
NH3
NH
HNO
NHNN
O
O O
OH2N
O
H3N
HN
NH
O
NHNN
O
O O
OH2N
O
NH3
HN
NHO
NH
NN
O
O O
OH2N
O
H3N
HN
NH
O
NH
NN
O
O O
OH2N
O
H3N
HN
NH
4
Figure S1. Structure of zipper components 1, 3 and 4 (see Scheme S1 for 2). For design details
for zipper assembly, see ref. [S3], Figures S2 and S3 (intrastack H-bonded chains and interstack ion
pairing).
S16
Cathodic current
Anodic current
-1.5-1-0.500.511.5
V (vs Fc/Fc+
)
Fig. S2. Representative cyclic voltammogram for N,Cl-NDI 7.
Figure S3. Intensity-normalized absorption spectra of the investigated dyes in MeOH.
S17
Figure S4. Intensity-normalized fluorescence spectra of the investigated dyes in MeOH.
1114
Figure S5. Fluorescence quenching of a constant concentration of 2a by bianisole 14 and p-
quateranisole 11 in acetonitrile.
S18
Figure S6. Intensity-normalized time profiles of the transient absorption of 2 at 470 nm and of
4 at 511 nm.
A
Rel
ativ
e ph
otoc
urre
nt
B
0
10
20
30
0 1 2 3 4
layers
0.8
1
1.2
1.4
1.6
520 560 600 640 680
Ab
s
nm
0
0.02
0.04
0.06
520 560 600 640 680
Ab
s
nm
C
Fig. S7. A. Build up of mixed multi-layers, evidenced by increase in relative photocurrent.
Blue filled circles, Au-1-4-3-4; red filled diamonds, Au-1-2-3-2; pink open circles, Au-1-2-3-4;
purple triangles, Au-1-4-3-2. Error bars represent standard deviation of five independent
experimental data. B and C. As measured (B) and baseline corrected (C) absorption spectra of
multi-layers on the gold plates. Blue solid line, Au-1-4-3-4; red dotted line, Au-1-2-3-2; purple
broken line, Au-1-2-3-4, grey solid line, gold plate.
S19
Comment on Fig. S7: The huge increase in photocurrent induced by the deposition of red layer
(Fig. S7A) indicated that rNDIs are much better chromophores than bNDIs. This conclusion was
supported by the action spectra (Fig. 3b), in which photocurrent generated by irradiation on the
absorption of bNDI was nearly negligible compared to that by rNDI. Note, the mismatch between
the action spectra (Fig. 3b) and UV-vis absorption spectra (Fig. S7C), which confirmed the presence
of bNDI chromophores in all the layers. Due to the scattering caused by the gold film (Fig. S7B
grey line), it was not possible to unambiguously quantify the two chromophores in the mixed layers.
Nevertheless, the presence of higher concentration of bNDI ( max = 620 nm) in Au-1-4-3-4 (blue
solid line), or higher concentration of rNDI ( max = 532 nm) in Au-1-2-3-2 (red dotted line)
compared to the others could be seen in both absorption spectra (Fig. S7B and C).
S20
BR
POPTEOA
A H I
b) e–
a) e–
c) energy
B e–Ee–
e–e–
e–
DC
F
a) b)
c)
h hh
d) e–
e) e–
d)
e)
e– G
f)g)
g)
Jf)
Fig. S8. Possible pathways of electron transfer cascades. HOMO (solid lines) and LUMO
levels (dashed lines) of rNDI (“R” in A, red), bNDI (“B” in A, blue), p-octiphenyls (“POP” in A,
grey) and TEOA (green). Orange rectangle represents the gold electrode.
Comment on Fig. S8: Upon photo-excitation of rNDI (A), exciton (B) is generated. Thus
formed hole would be filled by the electron transfer from (or hole transfer to) oligophenyl to give
the charge separated state with a radical anion on rNDI and a radical cation on the oligophenyl (C,
via path a). Alternatively if the electron transfer takes place from bNDI (path b), radical cation
would be on the bNDI in the resulting charge separated state D. A hole on the oligophenyl in C
S21
should be eventually transferred to TEOA in the solution (F) directly (path d) or via bNDI (D, path
e), while the electron on rNDI should be injected to the gold electrode (G). Photo-excitation of
bNDI (H) or energy transfer from excited rNDI B (path c) would generate bNDI exciton (E). The
electron transfer to rNDI (giving D) and subsequent steps discussed above should give rise to G.
Similarly, excited oligophenyl (J) could transfer energy to rNDI (path f) and/or bNDI (path g,
giving B and E, respectively), or transfer electron to rNDI (directly or via bNDI) to give charge
separated state C. All these intermediate states should follow the paths described above to finally
give G.
S22
4. Supplementary tables
Table S1 Electrochemical and spectroscopic data
Dye E1/2 (X/X
+)
V vs Fc/Fc+
EHOMO
EV
E1/2 (X/X-)
V vs
Fc/Fc+
ELUMO
eV
abs ( calc)
nm
4ca +0.62 -5.4 -1.33 -3.5 620 (636)
4bb +0.60 -5.4 -1.40 -3.4 620 (620)
2bb (+1.01)
c (-5.8)c -1.24 -3.6 532 (550)
d
7 +1.21 -6.0 -1.10 -3.7 536 (537)
11 +1.10e -5.9
12f +0.98 -5.8 -2.77 -2.1
13g +0.79 -5.6 -2.20 -2.6
afrom ref [S3];
bfrom ref [S4];
ccalculated from absorption (see d);
destimated from the average
wavelength of absorption and emission maxima; eirreversible, EPA is listed;
ffrom ref [S5] and E1/2
(Fc/Fc+) = 0.49 V (vs Ag/AgCl);
gestimated using eqs (1) and (2) in ref [S5] and E1/2 (Fc/Fc
+) =
0.49 V (vs Ag/AgCl).
N
NO O
OO
NH2
OR
NHAlloc
NH
HN
N
N OO
O O
C8H17
C8H17
C8H17
HN
H17C8NH
4b
N
N OO
O O
C8H17
C8H17
ClH17C8
NH
2b4a: R = (CH2)2-NH2
4c: R = COO-t-Bu
O
O
O
O
H Hn
12: n = 4
13: n = 8
n
11: n = 1
14: n = 0
S23
Table S2 Fluorescence quantum yields of the investigated dyes
Dye Solvent fl
4aa MeOH 0.25
4a MeOH 0.009
2a MeOH 0.06
2a CAN 0.43
2 MeOH 0.011
afrom ref [S1].
Table S3 Time constants and relative amplitudes (in brackets) used to reproduce the
fluorescence decay of the investigated systems.
Dye Solvent 1 (ps) 2 (ps) 3 (ps) 4 (ns) 5 (ns)
2a MeOH — — 115 (0.39) 1.6 (0.32) 6.0 (0.29)
2a CAN 1.7 (0.09) — 115 (0.13) — 9.4 (0.78)
2 MeOH 4.3 (0.24) 23 (0.44) 164 (0.26) 1.4 (0.03) 4.3 (0.02)
4aa
MeOH — — — — 8.4 (1.0)
4a
MeOH 7.1 (0.66) 51 (0.19) 160 (0.12) 1.8 (0.01) 7.3 (0.02)
afrom ref [S1].
S24
5. Supplementary references
[S1] S. Bhosale, A. L. Sisson, P. Talukdar, A. Fürstenberg, N. Banerji, E. Vauthey, G. Bollot, J.
Mareda, C. Röger, F. Würthner, N. Sakai, S. Matile, Science 2006, 313, 84-86.
[S2] B. Baumeister, N. Sakai, S. Matile, Org. Lett. 2001, 3, 4229-4232.
[S3] N. Sakai, A. L. Sisson, T. Bürgi, S. Matile, J. Am. Chem. Soc. 2007, 129, 15758-15759.
[S4] C. Thalacker, C. Röger, F. Würthner, J. Org. Chem. 2006, 71, 8098-8105.
[S5] K. Meerholz, J. Heinze, Electrochim. Acta 1996, 11/12, 1839.
[S6] Y. Yamamoto, T. Fukushima, Y. Suna, N. Ishii, A. Saeki, S. Seki, S. Tagawa, M.
Taniguchi, T. Kawai, T. Aida, Science 2006, 314, 1761-1764;
[S7] F. Würthner, S. Ahmed, C. Thalacker, T. Debaerdemaeker, Chem. Eur. J. 2002, 8, 4742-
4750.
[S8] J. R. Lakowicz, Principles of Fluorescence Spectroscopy, 2nd
ed. 1999, New York: Kluwer
Academic.
[S9] A. Morandeira, L. Engeli, E. Vauthey, J. Phys. Chem. A 2002, 106, 4833-4837.
[S10] M. Twardowski, R. Nuzzo, Langmuir 2002, 18, 5529-5538.
[S11] M. D. Porter, T. B. Bright, L. David, D. L. Allara, C. E. D. Chidsey, J. Am. Chem. Soc.
1987, 109, 3559-3568.