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Reactivity and structure of derivatives of 2-hydroxy-1,4-naphthoquinone (lawsone)
(2007-11)
The structures of two derivatives of 2-hydroxy-1,4-naphthoquinone (lawsone) are examined using the density functional theory (DFT) hybrid functional B3LYP. Using the optimized structure of lawsone acetate, the reactivity ...
Neutral organic redox pairs based on sterically hindered hydroquinone/benzoquinone derivatives for dye-sensitized solar cells
(2018-06)
Substituted derivatives of hydroquinone/benzoquinone were studied as organic redox mediators in the electrolyte for dye-sensitized solar cells (DSSCs). Thus, di-tert-butylhydroquinone (DTHQ), thymohydroquinone (ThymHQ) and ...
Grids III: Hydrogen Bridges in Introductory Chemistry
Cuadrículas III: Puentes de Hidrógeno en Química General
(2021)
Based on IUPAC recommendations for the
definition of the hydrogen bond, a series of
grids is presented to provide instructors of
introductory chemistry courses with visual
examples of H-bridged systems. The grids ...
General Chemistry Without Orbitals
(2020)
We illustrate the solutions of Schroedinger's equation for the hydrogen atom in coordinates of all four systems, and differentiate the applicability of orbitals in these four systems. We present reasons that future textbooks ...
Synthesis of 2-hydroxy-3-substituted naphthoquinones using the Heck reaction
(2007-06)
An efficient Heck coupling of 2-hydroxy-3-iodo-naphthoquinone with a series of electron-deficient alkenes in aqueous solution has been accomplished. The method is characterized by simple conditions and facile work-up to ...
Crystal structure of (E)-2-(tert-butylamino)-4-(tertbutylimino)naphthalen-1(4H)-one
(2018)
The title compound, C18H24N2O, is the first example of a naphthoquinone imine derivative isolated in the 4-imine/2-amine tautomeric form having bulky alkyl substituents at the N atoms. The molecular conformation is stabilized ...
Efficient syntheses of streptocarpone and (±)-a-dunnione
(2007)
An efficient divergent synthesis of both streptocarpone and racemic α-dunnione from lawsone are described. A one-pot, formal [3+2] cyclization to form a furanonaphthoquinone directly provided a common intermediate.
Sudoku Puzzles for First-Year Organic Chemistry Students
(2007-04)
We use sudoku puzzles to help the students (i) learn the correspondence between the names of the amino acids, their abbreviations, and codes and (ii) learn the correspondence between the names of the functional groups, ...
Synthesis and biological evaluation of novel ferrocene–naphthoquinones as antiplasmodial agents
(2013-12)
This work deals with the synthesis and evaluation of new compounds designed by combination of 1,4-naphthoquinone and ferrocene fragments in a 3-ferrocenylmethyl-2-hydroxy-1,4-naphthoquinone arrangement. A practical coupling ...
Orbitals in general chemistry, Part II: Mathematical Realities
(2021)
In Part II of a three-part series, we discuss two factors absent from textbooks of general chemistry that are important in a discussion
of teaching orbitals. First, atomic orbitals are shown systematically to comprise ...