Oxidation of bisnaphthols to spironaphthalenones, revisited

Abstract

Bis(2-hydroxy-1-naphthyl)methane derivatives have been efficiently converted to their corresponding spirans through three methods, i.e. oxidation by TCCA under mild reaction conditions, Ph 3 Bi catalyzed air oxidation, and by electrochemical reaction. The first two methods are diastereoselective and give either of the two possible diastereomers, while the electrochemical method produces equal amounts of these diastereomers.

Stable and catalytically active iron porphyrin-based porous organic polymer: Activity as both a redox and Lewis acid catalyst

“…Several reagents have been used to oxidize bis(2-hydroxy-1-naphthyl)methanes as a subunit of calix[n]arene to the corresponding spirodienones. These include phenyltrimethylammonium tribromide (PTMATB) 47 , 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) 48 , N -chloro reagents 49 , Ph 3 Bi 50 and nanoparticle-supported TEMPO 51 (2,2,6,6-tetramethylpiperidine-oxyl).…”

Selective Oxidation of 8,8′-Hydroxylated Binaphthols to Bis-spironaphthalenones or Binaphtho-para- and Binaphtho-ortho-quinones

“…These natural products include grandidone D 16 and the spiroxins A-E. 17 In addition, compounds containing a carbonyl adjacent to a spirodihydrobenzofuran have been reported, which include calixarenes 18 and spironaphthalenones. 19 Due to the unusual structure of 3 , derivatization and investigation of its reactivity was pursued.…”

Aerobic Copper Catalytic Oxidation of Methylene and Arylidenebisnaphthols: A Green and Efficient Synthesis of Spironaphthalenones

“…Depending on the conditions, the reaction proved to be stereoselective,,, or lead to a mixture of diastereoisomers ,,. Moreover, the reaction conditions are very often stoichiometric and only more recently catalytic conditions were reported.…”

“…An exception was the use of triphenylbismuth as catalyst, which was found efficient in stereoselectivity. We have decided to try to reproduce the catalytic oxidation of 4,4’‐(phenylmethylene)bis(naphthalen‐2‐ol) 2 f by triphenylbismuth according to the description of Khoramadi‐zad et al .…”

“…An exception was the use of triphenylbismuth as catalyst, which was found efficient in stereoselectivity. We have decided to try to reproduce the catalytic oxidation of 4,4’‐(phenylmethylene)bis(naphthalen‐2‐ol) 2 f by triphenylbismuth according to the description of Khoramadi‐zad et al . Surprisingly, we did not obtain any oxidation product but only the dehydration product of 2 f : the 14‐(phenyl)‐14H‐dibenzo[a,j]xanthene (see experimental part).…”