A. Ghosh and M. Ravikanth
refining on F2.[21] The positions of all the atoms were obtained by direct
methods. All non-hydrogen atoms were refined anisotropically. The re-
maining hydrogen atoms were placed in geometrically constrained posi-
tions and refined with isotropic temperature factors, typically 1.2Ueq of
their parent atoms.
tigating the excited-state dynamics of these PV complexes of
meso-triarylcorroles.
Conclusion
CCDC-837991 (1) and CCDC-837992 (4) contain the supplementary crys-
tallographic data for this paper. These data can be obtained free of
charge from The Cambridge Crystallographic Data Centre via
We have prepared a series of PV complexes of meso-triaryl-
corroles and characterized them by using various spectro-
scopic techniques. Detailed NMR spectroscopic studies indi-
cated that the PV–meso-triarylcorroles preferentially existed
in hexacoordinate environments in coordinating solvents
(CH3OH, THF, DMSO, etc.) and dissociated to their penta-
coordinate complexes in non-coordinating solvents, (toluene,
CH2Cl2, and CHCl3). X-ray crystal data for two complexes
confirmed the hexacoordinate geometry of the PV–meso-tri-
arylcorroles. Their optical and electrochemical properties
were very interesting and distinct compared to PV–meso-tet-
raarylporphyrins. Unlike PV–meso-tetraarylporphyrins, the
PV–meso-triarylcorroles were very brightly fluorescent with
high quantum yields, and will be very useful for various mo-
lecular device applications.
General synthesis: Free-base meso-triarylcorroles were synthesized ac-
cording to literature procedures.[22] Phosphorus derivatives 1–7 were syn-
thesized by heating a solution of the corresponding free-base meso-triar-
ylcorrole in pyridine at reflux in the presence of excess POCl3 (about
a 100-fold excess).
Synthesis of compound 1: To
a solution of 5,10,15-triphenylcorrole
(100 mg, 0.189 mmol) in dry pyridine (10 mL) was added POCl3 (1.8 mL,
19.25 mmol) and the reaction mixture was heated to reflux for 15 min
under a nitrogen atmosphere. The solution immediately changed from
a deep green color to a purple-violet color with a greenish tint. The prog-
ress of reaction was monitored by TLC analysis and its completion was
determined by absorption spectroscopy. After completion of reaction, the
solvent was evaporated under reduced pressure. The crude solid was sub-
jected to column chromatography on basic alumina and the desired com-
pound was collected from a greenish pink-violet-colored band by eluting
with CH2Cl2. The solvent was removed on a rotary evaporator to afford
a
deep purple-violet solid. The compound was recrystallized from
CH2Cl2/n-hexane (1:3) to afford compound 1 as a purple solid in 78%
yield (87 mg, 0.148 mmol). 1H NMR (400 MHz, CD3OD): d=9.38 (dd, 3J-
(P,H)=2.6 Hz, 2H; b-pyrrole H), 9.03 (dd, 3J
ACHUTGTNRENNUG ACHTUNGTRENNUNG
(H,H)=
(H,H)=4.4 Hz, 4J
(H,H)=4.9 Hz, 4J
(P,H)=
Experimental Section
A
ACHUTNGRENNUG CAHTUNGTRENNUNG
(P,H)=3.6 Hz, 2H; b-pyrrole H), 8.95 (dd, 3J
A
ACHTUNGTRENNUNG
Chemicals: All chemicals and solvents were purchased from S.D. Fine
Chemicals (India). Column chromatography was performed on silica gel
and basic alumina that were obtained from Sisco Research Laboratories
(India). Tetrabutylammonium perchlorate was purchased from Fluka and
used without further purification. All NMR solvents were used as re-
ceived. CH2Cl2, THF, and n-hexane were purified and distilled according
to standard procedures.
3.0 Hz, 2H; b-pyrrole H), 8.25–8.28 (m, 4H; Ar H), 8.15–8.17 (m, 2H;
Ar H), 7.78–7.87 ppm (m, 9H; Ar H); 31P{1H} NMR (400 MHz,
CD3OD): d=À178.03 ppm; HRMS: m/z: 571.1697 [MÀ17]+.
Compounds 2–7 were prepared by following the same synthetic route
mentioned for compound 1.
Compound 2: Compound 2 was obtained as a pink-violet solid in 80%
yield (88 mg, 0.132 mmol). 1H NMR (400 MHz, CD3OD): d=9.43 (dd, 3J-
Instrumentation: 1H and 31P{1H} NMR spectra were recorded on
a Bruker AVANCE III 400 MHz spectrometer. Tetramethylsilane (TMS)
was used as an internal reference for the 1H NMR spectra (residual
proton; d=7.26 ppm in CDCl3) and 85% H3PO4 was used as an external
reference for the 31P NMR spectra (CDCl3 and CD3OD). HRMS was per-
formed on a Q-Tof micromass spectrometer. Absorption and steady-state
fluorescence spectra were obtained on Perkin–Elmer Lambda-35 and ISS
(US) PC1 Photon-Counting spectrofluorometers, respectively. The fluo-
rescence quantum yield (Ff) of PV meso-triaryl corroles 1–7 were estimat-
ed from their emission and absorption spectra by using the comparative
A
(P,H)=2.4 Hz, 2H; b-pyrrole H), 9.02 (dd, 3J
ACHUTGTNRENNUG ACHTUNGTRENNUNG
ACHUTNGRENNUG CAHTUNGTRENNUNG
(P,H)=3.7 Hz, 2H; b-pyrrole H), 8.96 (dd, 3J
A
ACHTUNGTRENNUNG
2.9 Hz, 2H; b-pyrrole H), 8.34–8.46 (m, 5H; Ar H), 8.15–8.21 ppm (m,
7H; Ar H); 31P{1H} NMR (400 MHz, CD3OD): d=À184.79 ppm;
HRMS: m/z: 646.1515 [MÀ17]+.
Compound 3: Compound 3 was obtained as a dark violet solid in 75%
yield (82 mg, 0.121 mmol). 1H NMR (400 MHz, CD3OD): d=9.34 (dd, 3J-
A
(P,H)=2.6 Hz, 2H; b-pyrrole H), 9.03 (dd, 3J
ACHUTGTNRENNUG ACHTUNGTRENNUNG
method[20] with [H
rescence-decay measurements were carried out at the magic angle by
using picosecond-diode-laser-based time-correlated single-photon-
2ACHTUNGTRENNUNG(TPP)] as a standard (Ff =0.11). Time-resolved fluo-
AHCTUNGTRENNUNG
A
ACHTUNGTRENNUNG
a
2H; b-pyrrole H), 8.52–8.54 (m, 2H; Ar H), 8.16–8.18 (m, 3H; Ar H),
8.04–8.06 (m, 2H; Ar H), 7.78–7.87 (m, 1H; Ar H), 7.33–7.45 (m, 4H;
Ar H), 4.06–4.08 ppm (m, 9H, OCH3); 31P{1H} NMR (400 MHz,
CD3OD): d=À178.08 ppm; HRMS: m/z: 679.2129 [M]+.
counting (TCSPC) fluorescence spectrometer from IBH (UK). All decay
curves were fitted to single exponential functions by using IBH software.
Cyclic voltammetry (CV) and differential pulse voltammetry (DPV)
were carried out with a BAS electrochemical system by utilizing a three-
electrode configuration that consisted of a glassy carbon working elec-
trode, a platinum wire auxiliary electrode, and a saturated calomel refer-
ence electrode. The experiments were performed in dry MeCN with 0.1m
tetrabutylammonium perchlorate as the supporting electrolyte.
Compound 4: Compound 4 was obtained as a dark violet solid in 81%
yield (89 mg, 0.128 mmol). 1H NMR (400 MHz, CD3OD): d=9.42 (dd, 3J-
(H,H)=4.4 Hz, 4J(P,H)=2.6 Hz, 2H; b-pyrrole H), 9.05 (dd, 3J
AHCTUNGTRENGNUN ACHTUNRTGENNUNG ACHTUNGTRENNUNG(H,H)=
4
4
5.0 Hz, J
N
ACHTUNGTRENNUNG
A
G
ACHTUNGTRENNUNG
X-ray crystallography: Single-crystal X-ray analysis of compounds 1 and
4 were performed on a CCD Oxford Diffraction XCALIBUR-S diffrac-
tometer that was equipped with an Oxford Instruments low-temperature
attachment. Data were collected at 293(2) for compound 1 and at
150(2) K for compound 4 using graphite-monochromated MoKa radiation
(la =0.71073 ꢁ). The strategy for data collection was evaluated by using
the CrysAlisPro CCD software. The data were collected by the standard
phi-omega scan techniques, and were scaled and reduced by using CrysA-
lisPro RED software. The structures were solved by direct methods using
SHELXS-97 and refined by full-matrix least-squares with SHELXL-97,
3.0 Hz, 2H; b-pyrrole H), 8.52–8.54 (m, 1H; Ar H), 8.12–8.14 (m, 3H;
Ar H), 8.23–8.25 (m, 2H; Ar H), 7.80–7.87 (m, 5H; Ar H), 7.42–
7.45 ppm (m, 1H; Ar H); 31P{1H} NMR (400 MHz, CD3OD): d=
À177.89 ppm; HRMS: m/z: 692.0707 [M+1]+.
Compound 5. Compound 5 was obtained as a dark blue-violet solid in
79% yield (85 mg, 0.103 mmol). 1H NMR (400 MHz, CD3OD): d=9.43
(dd, 3J
A
N
ACHTUNGTRENNUNG(H,H)=
4
4
4.5 Hz, J
N
ACHTUNGTRENNUNG
6394
ꢀ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Eur. J. 2012, 18, 6386 – 6396