90-53-9Relevant articles and documents
PYRANOQUINAZOLINE DERIVATIVES AND NAPHTHOPYRAN DERIVATIVES
-
Paragraph 0196-0197, (2020/05/14)
[Problem] A problem is presented in that conventional photochromic compounds cannot be considered adequate in terms of the colorizing/decolorizing rate and durability, and the production process therefore has many steps. The present invention provides an industrially applicable photochromic compound that has both a rapid colorizing/decolorizing reaction and high durability and can also be synthesized at a low cost. [Solution] This compound is characterized in that etheric oxygen atoms are bonded to the carbon atoms at position 1 of a pyranoquinazoline (8H-pyrano[3,2-f]quinazoline) skeleton and position 10 of a naphthopyran (3H-naphtho[2,1-b]pyran) skeleton, said compound having photochromic properties and being a photochromic compound that has both a rapid colorizing/decolorizing reaction and high durability. Also provided is an industrially applicable photochromic compound that can be synthesized at a low cost.
An improved and versatile method for the rapid synthesis of aryldihydrobenzofuran systems by a boron tribromide-mediated cyclization reaction
Detterbeck, Richard,Hesse, Manfred
, p. 343 - 360 (2007/10/03)
Boron tribromide is presented as a highly reactive reagent that simultaneously allows the demethylation and fully diastereoselective cyclization of different precursor molecules, obtained by an aldol-type reaction, to a series of hydroxylated aryldihydrobenzofuran systems in racemic form. The latter are often found as key structures in natural compounds of different classes. Syntheses of educts, which mainly took advantage of a versatile Rieche formylation, are also described.
A convenient entry into the rhoeadan skeleton. Total synthesis of (±)-cis-alpinigenine
Ahmad,Snieckus
, p. 2678 - 2686 (2007/10/02)
-