Chlorophyll-porphyrin heterodimers with orthogonal. pi. systems: Solvent polarity dependent photophysics

Journal Article · Wed Aug 29 00:00:00 EDT 1990 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00174a005· OSTI ID:5379304

Wasielewski, M R; Johnson, D G; Niemczyk, M P; Gaines, III, G L; O'Neil, M P; Svec, W A ^[1]

---

1. Argonne National Lab., IL (USA)

The synthesis and properties of a series of fixed-distance chlorophyll-porphyrin molecules are described. These molecules consist of a methyl pyrochlorophyllide a moiety which is directly bonded at its 2-position to the 5-position of a 2,8,12,18-tetraethyl-3,7,13,17-tetramethyl-15-(p-tolyl)porphyrin. Steric hindrance between adjacent substituents rigidly positions the {pi} systems of both macrocycles perpendicular to one another. The macrocycles were selectively metalated with zinc to give the four possible derivatives, HCHP, ZCHP, HCZP, and ZCZP, where H, Z, C, and P denote free base, Zn derivative, chlorin, and porphyrin, respectively. The lowest excited singlet states of HCHP and ZCHP, which are localized on HC and ZC, respectively, exhibit lifetimes and fluorescence quantum yields that are solvent polarity independent and do not differ significantly from those of chlorophyll itself. ZCZP, however, displays a lowest excited singlet state and lifetime and fluorescence quantum yield that are strongly solvent polarity dependent.

• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5379304
• Journal Information: Journal of the American Chemical Society; (United States), Vol. 112:18; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CHLOROPHYLL
PHOTOCHEMISTRY
SYNTHESIS
PORPHYRINS
ABSORPTION SPECTRA
DIMERS
ENERGY LEVELS
EXCITED STATES
PHOTOSYNTHETIC REACTION CENTERS
CARBOXYLIC ACIDS
CHEMISTRY
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHYTOCHROMES
PIGMENTS
PROTEINS
SPECTRA
140505* - Solar Energy Conversion- Photochemical
Photobiological
& Thermochemical Conversion- (1980-)
400500 - Photochemistry