skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Synthesis of covalently linked dimeric derivatives of chlorophyll a, pyrochlorophyll a, chlorophyll b, and bacteriochlorophyll a

Abstract

Bis(chlorophyllide) ethylene glycol diesters were prepared for each of the title compounds. Pheophytins a and b isolated from alfalfa and bacteriochlorophyll a isolated from R. sphaeroides were treated with 80% aqueous trifluoroacetic acid to yield the corresponding pheophorbides. Pyropheophorbide was prepared by a literature procedure. Carbonic anhydride and benzotriazole-1-methanesulfonate activation methods were used in the esterification of the pheophorbides with ethylene glycol at ambient temperature. Each method yielded 75%+ of the pheophorbide ethylene glycol monoester. These monoesters were treated with equimolar amounts of the corresponding pheophorbide by using benzotriazol-1-methanesulfonate/4-(dimethylamino)pyridine in CH/sub 2/Cl/sub 2/ or dicyclohexylcarbodiimide/4-(dimethylamino)pyridine in CH/sub 2/Cl/sub 2/ at ambient temperature. Yields of bis(phenophorbide) ethylene glycol diesters averaged about 50% for the former method and 70% for the latter method. Insertion of the magnesium atoms into the a series macrocycles was accomplished with iodomagnesium 2,6-di-tert-butyl-4-methylphenolate, IMgBHT, in CH/sub 2/Cl/sub 2/, while the metalation of the b and bacterial series macrocycles was carried out with a mixture of IMgBHT and lithium 2,2,6,6-tetramethylpiperidide in thiophen, all at ambient temperature. Both mono- and dimetalated derivatives were isolated and characterized in each case.

Authors:
;
Publication Date:
Research Org.:
Argonne National Lab., IL
OSTI Identifier:
5134441
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Org. Chem.; (United States); Journal Volume: 45:10
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 59 BASIC BIOLOGICAL SCIENCES; ESTERS; CHEMICAL PREPARATION; GLYCOLS; LITHIUM COMPLEXES; ORGANOMETALLIC COMPOUNDS; BINDING ENERGY; CHLOROPHYLL; ELECTRONS; PHOTOSYNTHESIS; VALENCE; ALCOHOLS; CARBOXYLIC ACIDS; CHEMICAL REACTIONS; COMPLEXES; ELEMENTARY PARTICLES; ENERGY; FERMIONS; HETEROCYCLIC ACIDS; HETEROCYCLIC COMPOUNDS; HYDROXY COMPOUNDS; LEPTONS; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; PHOTOCHEMICAL REACTIONS; PHYTOCHROMES; PIGMENTS; PORPHYRINS; SYNTHESIS; 400201* - Chemical & Physicochemical Properties; 400301 - Organic Chemistry- Chemical & Physicochemical Properties- (-1987); 550200 - Biochemistry

Citation Formats

Wasielewski, M.R., and Svec, W.A. Synthesis of covalently linked dimeric derivatives of chlorophyll a, pyrochlorophyll a, chlorophyll b, and bacteriochlorophyll a. United States: N. p., 1980. Web. doi:10.1021/jo01298a043.
Wasielewski, M.R., & Svec, W.A. Synthesis of covalently linked dimeric derivatives of chlorophyll a, pyrochlorophyll a, chlorophyll b, and bacteriochlorophyll a. United States. doi:10.1021/jo01298a043.
Wasielewski, M.R., and Svec, W.A. Fri . "Synthesis of covalently linked dimeric derivatives of chlorophyll a, pyrochlorophyll a, chlorophyll b, and bacteriochlorophyll a". United States. doi:10.1021/jo01298a043.
@article{osti_5134441,
title = {Synthesis of covalently linked dimeric derivatives of chlorophyll a, pyrochlorophyll a, chlorophyll b, and bacteriochlorophyll a},
author = {Wasielewski, M.R. and Svec, W.A.},
abstractNote = {Bis(chlorophyllide) ethylene glycol diesters were prepared for each of the title compounds. Pheophytins a and b isolated from alfalfa and bacteriochlorophyll a isolated from R. sphaeroides were treated with 80% aqueous trifluoroacetic acid to yield the corresponding pheophorbides. Pyropheophorbide was prepared by a literature procedure. Carbonic anhydride and benzotriazole-1-methanesulfonate activation methods were used in the esterification of the pheophorbides with ethylene glycol at ambient temperature. Each method yielded 75%+ of the pheophorbide ethylene glycol monoester. These monoesters were treated with equimolar amounts of the corresponding pheophorbide by using benzotriazol-1-methanesulfonate/4-(dimethylamino)pyridine in CH/sub 2/Cl/sub 2/ or dicyclohexylcarbodiimide/4-(dimethylamino)pyridine in CH/sub 2/Cl/sub 2/ at ambient temperature. Yields of bis(phenophorbide) ethylene glycol diesters averaged about 50% for the former method and 70% for the latter method. Insertion of the magnesium atoms into the a series macrocycles was accomplished with iodomagnesium 2,6-di-tert-butyl-4-methylphenolate, IMgBHT, in CH/sub 2/Cl/sub 2/, while the metalation of the b and bacterial series macrocycles was carried out with a mixture of IMgBHT and lithium 2,2,6,6-tetramethylpiperidide in thiophen, all at ambient temperature. Both mono- and dimetalated derivatives were isolated and characterized in each case.},
doi = {10.1021/jo01298a043},
journal = {J. Org. Chem.; (United States)},
number = ,
volume = 45:10,
place = {United States},
year = {Fri May 09 00:00:00 EDT 1980},
month = {Fri May 09 00:00:00 EDT 1980}
}