Synthesis of a cofacial chlorin dimer of defined symmetry

Thanh, Nguyễn Thị; Könekamp, Thorsten; Hanke, Daniela; Löwer, Franziska; Borrmann, Tobias; Montforts, Franz‐Peter

doi:10.1142/s1088424612500666

Cited by 7 publications

(10 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such splitting has been reported previously for cofacial chlorin dyads, and it was attributed to the presence of two conformers in the excited state. 50 This is likely the case here. Relative to monomer C-PE, Φ f for phen-2C is much reduced (1.6-fold) but not as extensively as in the case of cis-2C (4.1-fold, Table 1).…”

Section: ■ Results and Discussionmentioning

confidence: 67%

“…There have been extensive studies performed on chlorosome models, in which semisynthetic chlorins or bacteriochlorins self-assemble into oligomers, , where individual hydroporphyrins strongly interact with one another. There are also several examples of synthetic, covalently linked cofacial − or directly linked , arrays. For some of such arrays, evidence for excitonic coupling is observed; however, hydroporphyrin arrays have been investigated much less extensively than corresponding porphyrinic systems.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Photoisomerization of Enediynyl Linker Leads to Slipped Cofacial Hydroporphyrin Dyads with Strong Through-Bond and Through-Space Electronic Interactions

Meares

Bhagavathy

et al. 2019

J. Org. Chem.

View full text Add to dashboard Cite

Photoisomerization of 3,4-di(methoxycarbonyl)-enediyne linker in hydroporphyrin (chlorin or bacteriochlorin) dyads leads to thermally stable cis isomers, where macrocycles adopt a slipped cofacial mutual geometry with an edge-to-edge distance of ∼3.6 Å (determined by density functional theory (DFT) calculations). Absorption spectra exhibit a significant splitting of the long-wavelength Qy band, which indicates a strong electronic coupling with a strength of V = ∼477 cm–1 that increases to 725 cm–1 upon metalation of hydroporphyrins. Each dyad features a broad, structureless emission band, with large Stokes shift, which is indicative of excimer formation. DFT calculations for dyads show both strong through-bond electronic coupling and through-space electronic interactions, due to the overlap of π-orbitals. Overall, geometry, electronic structure, strength of electronic interactions, and optical properties of reported dyads closely resemble those observed for photosynthetic special pairs. Dyads reported here represent a novel type of photoactive arrays with various modes of electronic interactions between chromophores. Combining through-bond and through-space coupling appears to be a viable strategy to engineer novel optical and photochemical properties in organic conjugated materials.

show abstract

Section: ■ Results and Discussionmentioning

confidence: 67%

Section: Introductionmentioning

confidence: 99%

Photoisomerization of Enediynyl Linker Leads to Slipped Cofacial Hydroporphyrin Dyads with Strong Through-Bond and Through-Space Electronic Interactions

Meares

Bhagavathy

et al. 2019

J. Org. Chem.

View full text Add to dashboard Cite

show abstract

“…Examples include two chlorins joined via an amide linkage ( Dyad-14 ) 215 and two chlorins joined via ethynyl groups to a biphenylene spacer ( Dyad-15 ). 219 The former was prepared by condensation of amino-chlorin Zn-91 and N -hydroxysuccinimidocarbonylchlorin Zn-92 (Scheme 31). The latter was prepared by use of the two iodochlorins Zn-90e and Zn-90f (Scheme 31).…”

Section: Smorgasbord Of Chlorinsmentioning

confidence: 99%

De NovoSynthesis of Gem-Dialkyl Chlorophyll Analogues for Probing and Emulating Our Green World

2015

View full text Add to dashboard Cite

Woodward reported his infamous synthesis of chlorin e 6 trimethyl ester, a known synthetic precursor to chlorophyll a. [59][60][61][62][63][64]124 The work was posited on a half-century of intensive studies by many investigators in tetrapyrrole chemistry and began a decade after the close of Fischer's lifetime of research 125−128 (which included an uncompleted synthetic program directed toward chlorophylls 15 ). Indeed, "he read all the umpteen papers on the chlorophylls written by Willstaẗter and Fischer, including the experimental parts." 129 The Woodward synthesis of chlorin e 6 trimethyl ester required 46 steps, of which 24 were spent on converting the sole precursor, Knorr's pyrrole, to the four pyrroles destined to form rings A−D; 7 additional steps accrued to obtain the dipyrromethanes that constitute the Eastern and Western halves (Scheme 13, the step numbers are identical to those shown in ref 64.). The first step formed the Knorr pyrrole (in several kg quantities), the next 24 steps were divided into four parallel paths, whereas the remaining 21 steps proceeded in linear fashion. Remarkable features of the synthesis include the directed intramolecular joining (via an imine) of the Eastern and Western halves (step 33), construction of the acrylate Scheme 10. Hydrogenation of a Porphyrin to Form a Chlorin Scheme 11. Representative meso-Tetraarylchlorins Scheme 12. Methyl Pyropheophorbide a

show abstract

“…The tricyclic nickel complex 9 (Scheme 2) which was used for several syntheses of chlorins in our laboratory is also an ideal intermediate for preparation of chlorins with the desired amino acid functionality. [22][23][24][25][26][27][28] The task therefore was to connect 9 with pyrrole ring D building blocks which contain annuleted cycloketone moieties as masked amino acid functions. Pyrroles 3 and 6 were chosen as starting materials for ring D building blocks (Scheme 1).…”

Section: Resultsmentioning

confidence: 99%

Synthesis of a chlorin with annelated lactam ring as subunit for artificial photosynthetic reaction centres

Montforts¹,

Haake²

2018

Arkivoc

Self Cite

View full text Add to dashboard Cite

A chlorin with an annelated cyclic ketone moiety was synthesized from a tricyclic nickel complex and appropriate pyrrole building blocks. Ketone functionality of the target chlorin allows Beckmann rearrangement to yield chlorin lactams. Lactam moieties on the chlorin represent masked amino acid structures which should allow formation of peptide-like backbones, along which chlorin pigments are arranged. Due to the "natural" chlorin chromophores and the peptide backbone the devices should represent artificial mimetics of natural photosynthesis systems.

show abstract

Synthesis of a cofacial chlorin dimer of defined symmetry

Cited by 7 publications

References 5 publications

Photoisomerization of Enediynyl Linker Leads to Slipped Cofacial Hydroporphyrin Dyads with Strong Through-Bond and Through-Space Electronic Interactions

Photoisomerization of Enediynyl Linker Leads to Slipped Cofacial Hydroporphyrin Dyads with Strong Through-Bond and Through-Space Electronic Interactions

De NovoSynthesis of Gem-Dialkyl Chlorophyll Analogues for Probing and Emulating Our Green World

Synthesis of a chlorin with annelated lactam ring as subunit for artificial photosynthetic reaction centres

Contact Info

Product

Resources

About