Synthesis and properties of covalently linked di-p-benzihomoporphyrin-BODIPY conjugates

Two mono meso-functionalized [20]di-[Formula: see text]-benzihomoporphyrins containing [Formula: see text]-formylphenyl and [Formula: see text]-iodophenyl groups at meso-position respectively were synthesized by condensing one equivalent of appropriate tetrapyrrane with one equivalent of [Formula: see text]-formyl benzaldehyde/[Formula: see text]-iodo benzaldehyde in CH2Cl2 under mild acid catalyzed conditions. The meso-formylphenyl and meso-iodophenyl functionalized di-[Formula: see text]-benzihomoporphyrins were used to synthesize two covalently linked di-[Formula: see text]-benzihomoporphyrins-BODIPY conjugates. The meso-formylphenyl-functionalized di-[Formula: see text]-benzihomoporphyrin was converted to corresponding meso-dipyrrolyl substituted di-[Formula: see text]-benzihomoporphyrin by treating with excess pyrrole under acid catalyzed conditions. In the next step, the meso-dipyrrolyl di-[Formula: see text]-benzihomoporphyrin was subjected to oxidation followed by BF2 complexation to afford the directly linked di-[Formula: see text]-benzihomoporphyrin-BODIPY conjugate. The meso-iodophenyl functionalized di-[Formula: see text]-benzihomoporphyrin was coupled with ethynyl-functionalized BODIPY under mild Pd(0) coupling condition to synthesize diphenylethyne-bridged di-[Formula: see text]-benzihomoporphyrin-BODIPY conjugate. The two conjugates were characterized by HR-MS, NMR, absorption, electrochemical, fluorescence and DFT studies. The spectral and electrochemical studies indicated that the two constituents, di-[Formula: see text]-benzihomoporphyrin and BODIPY units in the conjugates interact weakly and retain their individual characteristic features. DFT studies indicated a possibility of charge transfer between di-[Formula: see text]-benzihomoporphyrin and BODIPY units in conjugates.

Download Full-text

Synthesis and studies of covalently linked BODIPY-metal dipyrrin conjugates

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424619502067 ◽

2020 ◽

Vol 24 (05n07) ◽

pp. 938-946

Author(s):

Prosenjit Isar ◽

Mangalampalli Ravikanth

Keyword(s):

2D Nmr ◽

Individual Characteristic ◽

Metal Salts ◽

Dft Studies ◽

Chromatographic Purification ◽

2D Nmr Spectroscopy ◽

Td Dft ◽

Characteristic Features ◽

Covalently Linked ◽

Column Chromatographic

Three new covalently linked BODIPY-metal dipyrrin conjugates (Pd[Formula: see text], Zn[Formula: see text] and Re[Formula: see text] were synthesized by treating [Formula: see text]-dipyrrinyl BODIPY with appropriate metal salts in toluene in the presence of triethylamine at 120[Formula: see text] C. The conjugates were isolated in decent yields either by recrystallization or by column chromatographic purification. The conjugates were thoroughly characterized by 1D and 2D NMR spectroscopy, absorption, cyclic voltammetry and DFT/TD-DFT studies. The studies revealed that the BODIPY and metal dipyrrin moieties in conjugates interact very weakly with each other and retain their individual characteristic features. The conjugates are electron deficient and non-fluorescent in nature.

Download Full-text

Synthesis and studies of covalently linked BF2-oxasmaragdyrin-BODIPY and BF2-oxasmaragdyrin-ferrocene dyads

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424613500041 ◽

2013 ◽

Vol 17 (01n02) ◽

pp. 157-164 ◽

Cited By ~ 7

Author(s):

Yogita Pareek ◽

Mangalampalli Ravikanth

Keyword(s):

Electron Transfer ◽

Energy Transfer ◽

Excited State ◽

Photoinduced Electron Transfer ◽

Individual Characteristic ◽

Electrochemical Studies ◽

Fluorescence Studies ◽

Coupling Conditions ◽

Characteristic Features ◽

Covalently Linked

Covalently linked BF2 -oxasmaragdyrin-BODIPY and BF2 -oxasmaragdyrin-ferrocene dyads were synthesized by coupling of meso-triaryl oxasmaragdyrin containing meso-iodophenyl group with meso-(p-ethynylphenyl) borondipyrromethene and α-ethynyl ferrocene respectively under mild Pd(0) coupling conditions. NMR, absorption and electrochemical studies indicated that the two moieties in the dyads retain their individual characteristic features. The fluorescence studies indicated a possibility of photoinduced singlet-singlet energy transfer from BODIPY unit to BF2 -oxasmaragdyrin unit in BF2 -oxasmaragdyrin-BODIPY dyad and photoinduced electron transfer from ferrocene unit to excited state of BF2 -oxasmaragdyrin unit in BF2 -oxasmaragdyrin-ferrocene dyad.

Download Full-text

Synthesis of A2B-type 22-oxacorroles bearing two different five-membered heterocycles at meso positions

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s108842461950144x ◽

2020 ◽

Vol 24 (01n03) ◽

pp. 432-439

Author(s):

Umasekhar Booruga ◽

Mangalampalli Ravikanth

Keyword(s):

2D Nmr ◽

Quantum Yields ◽

Electrochemical Studies ◽

2D Nmr Spectroscopy ◽

Nmr Studies ◽

Absorption Bands ◽

Aryl Group ◽

Fluorescence Quantum Yields ◽

Acid Catalyzed ◽

Mild Acid

A series of 22-oxacorroles containing mixed substituents such as either two five-membered heterocycles and one six-membered aryl group or three five-membered heterocycles at three meso positions were synthesized by 3 + 2 oxidative coupling of appropriate 16-oxatripyrrane and meso-substituted dipyrromethane under mild acid catalyzed conditions. The identities of the 22-oxacorroles were confirmed by the respective molecular ion peaks in HR-MS spectra and the structures were deduced by detailed 1D and 2D NMR spectroscopy. NMR studies clearly showed upfield or downfield shifts of core pyrrole and furan protons and inner NH protons depending on the type of substituent present at the meso positions. All 22-oxacorroles absorb in the 410–655 nm region, and the position of the absorption bands depends on the type of meso substituents. The A2B oxacorroles showed one broad and weak fluorescence band in the 600–700 nm region with low fluorescence quantum yields in the 0.05–0.12 range. Electrochemical studies revealed that the A2B-type 22-oxacorroles are easier to oxidize and also easier to reduce than triphenyl 22-oxacorroles. Thus, the electronic properties of 22-oxacorroles were significantly altered when six-membered aryl groups were replaced with five-membered heterocycles as reflected in spectral and electrochemical measurements.

Download Full-text

Donor–acceptor type A2B2porphyrins: synthesis, energy transfer, computational and electrochemical studies

Inorganic Chemistry Frontiers ◽

10.1039/c6qi00558f ◽

2017 ◽

Vol 4 (4) ◽

pp. 618-638 ◽

Cited By ~ 16

Author(s):

Sudipta Das ◽

Haamid R. Bhat ◽

Naresh Balsukuri ◽

Prakash C. Jha ◽

Yutaka Hisamune ◽

...

Keyword(s):

Energy Transfer ◽

Type A ◽

Electrochemical Studies ◽

Dft Studies ◽

Donor Acceptor

Synthesis, photophysical, electrochemical and DFT studies of donor–acceptor type A2B2porphyrins and their Zn(ii) and Pd(ii) complexes have been described.

Download Full-text