skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


  • NSF Public Access
  • Search Results
  • Heck reaction synthesis of anthracene and naphthalene derivatives as traps and clean chemical sources of singlet molecular oxygen in biological systems
Title: Heck reaction synthesis of anthracene and naphthalene derivatives as traps and clean chemical sources of singlet molecular oxygen in biological systems
Studies have previously shown that anthracene and naphthalene derivatives serve as compounds for trapping and chemically generating singlet molecular oxygen [O 2 ( 1 Δ g )], respectively. Simple and efficient synthetic routes to anthracene and naphthalene derivatives are needed, for improved capture and release of O 2 ( 1 Δ g ) in cellular environments. Because of this need, we have synthesized a dihydroxypropyl amide naphthlene endoperoxide as a O 2 ( 1 Δ g ) donor, as well as five anthracene derivatives as O 2 ( 1 Δ g ) acceptor. The anthracene derivatives bear dihydroxypropyl amide, ester, and sulfonate ion end groups connected to 9,10-positions by way of unsaturated (vinyl) and saturated (ethyl) bridging groups. Heck reactions were found to yield these six compounds in easy-to-carry out 3-step reactions in yields of 50–76%. Preliminary results point to the potential of the anthracene compounds to serve as O 2 ( 1 Δ g ) acceptors and would be amenable for future use in biological systems to expand the understanding of O 2 ( 1 Δ g ) in biochemistry.  more » « less
Award ID(s):
1856765
PAR ID:
10230692
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Photochemical & Photobiological Sciences
Volume:
19
Issue:
11
ISSN:
1474-905X
Page Range / eLocation ID:
1590 to 1602
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; (, Beilstein Journal of Organic Chemistry)
    We report the synthesis and characterization of naphthalene and anthracene scaffolds end-capped by cyclic imides. The solid-state structures of theN-phenyl derivatives, determined by X-ray crystallography, reveal changes in packing preference based on the number of aromatic rings in the core. The optical and electronic properties of the title compounds compare favorably with other previously described isomers and expand the toolbox of electron-deficient aromatic compounds available to organic materials chemists. 
    more » « less
  2. ; ; ; ; ; ; ; ; ; (, Applied mathematics and computation)
    In this paper, we prove bounds for the unique, positive zero of O  G (z) := 1 −O G (z) , where O G ( z ) is the so-called orbit polynomial [1]. The orbit polynomial is based on the multiplic- ity and cardinalities of the vertex orbits of a graph. In [1] , we have shown that the unique, positive zero δ≤1 of O  G (z) can serve as a meaningful measure of graph symmetry. In this paper, we study special graph classes with a specified number of orbits and obtain bounds on the value of δ. 
    more » « less
  3. ; ; ; ; ; ; (, Environmental Science: Water Research & Technology)
    null (Ed.)
    Peracetic acid (PAA) is being considered as a disinfectant in membrane-based wastewater reuse systems, but its compatibility with polyamide membranes has not been thoroughly investigated. In this work, we showed that PAA induced much less change in the performance and material characteristics of NF90 membranes than the traditional disinfectant free chlorine (NaOCl). The change in membrane water flux and the rejection of salt and neutral organic compounds after PAA exposure (1–180 g h L −1 ) is significantly less than that resulting from NaOCl exposure at levels as low as 1 g h L −1 . The presence of two wastewater constituents, chloride or Fe( ii ), did not significantly impact membrane performance upon exposure to PAA. Surface characterization showed that oxygen was incorporated into polyamide by PAA, some of which was attributed to the formation of carboxylic acid groups. Experiments using a model aromatic amide, benzanilide, indicated an unexpected role of PAA in protecting the membrane from radicals formed by Fe( ii ) and the H 2 O 2 present in commercial PAA formulations. Furthermore, product identification suggests that both amide bond breakage and ring oxidation are possible reaction mechanisms for PAA. Our findings support that PAA is a viable disinfectant candidate for wastewater reuse and warrants further evaluation. 
    more » « less
  4. ; ; (, Chemistry)
    Dicyano-functionalized benzene and naphthalene anion derivatives exhibit a relatively rich population of electronically excited states in stark contrast to many assumptions regarding the photophysics of anions in general. The present work has quantum chemically analyzed the potential electronically excited states of closed-shell anions created by replacing hydrogen atoms with valence-bound lone pairs in benzene and naphthalene difunctionalized with combinations of -CN and -C2H. Dicyanobenzene anion derivatives can exhibit dipole-bound excited states as long as the cyano groups are not in para position to one another. This also extends to cyanoethynylbenzene anions as well as deprotonated dicyano- and cyanoethynylnaphthalene anion derivatives. Diethynyl functionalization is less consistent. While large dipole moments are created in some cases for deprotonation on the -C2H group itself, the presence of electronically excited states beyond those that are dipole-bound is less consistent. Beyond these general trends, 2-dicyanonaphthalene-34 gives strong indication for exhibiting a quadrupole-bound excited state, and the 1-cyanoethynylnaphthalene-29 and -36 anion derivatives are shown to possess as many as two valence-bound excited states and one dipole-bound excited state. These photophysical properties may have an influence on regions where polycyclic aromatic hydrocarbons are known to exist such as in various astrochemical environments or even in combustion flames. 
    more » « less
  5. ; ; ; ; (, Mathematical Proceedings of the Cambridge Philosophical Society)
    Abstract May the triforce be the 3-uniform hypergraph on six vertices with edges {123′, 12′3, 1′23}. We show that the minimum triforce density in a 3-uniform hypergraph of edge density δ is δ 4– o (1) but not O ( δ 4 ). Let M ( δ ) be the maximum number such that the following holds: for every ∊ > 0 and $$G = {\mathbb{F}}_2^n$$ with n sufficiently large, if A ⊆ G × G with A ≥ δ | G | 2 , then there exists a nonzero “popular difference” d ∈ G such that the number of “corners” ( x , y ), ( x + d , y ), ( x , y + d ) ∈ A is at least ( M ( δ )–∊)| G | 2 . As a corollary via a recent result of Mandache, we conclude that M ( δ ) = δ 4– o (1) and M ( δ ) = ω ( δ 4 ). On the other hand, for 0 < δ < 1/2 and sufficiently large N , there exists A ⊆ [ N ] 3 with | A | ≥ δN 3 such that for every d ≠ 0, the number of corners ( x , y , z ), ( x + d , y , z ), ( x , y + d , z ), ( x , y , z + d ) ∈ A is at most δ c log(1/ δ ) N 3 . A similar bound holds in higher dimensions, or for any configuration with at least 5 points or affine dimension at least 3. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email