22439-65-2Relevant articles and documents
Synthesis of spirocyclic diarylfluorenes by one-pot twofold SNAr reactions of diaryl sulfones with diarylmethanes
Bhanuchandra,Yorimitsu, Hideki,Osuka, Atsuhiro
supporting information, p. 384 - 387 (2016/02/19)
Treatment of dibenzothiophene dioxides with cyclic diarylmethanes in the presence of KN(SiMe3)2 results in the formation of fluorene-based spirocyclic tetraarylmethanes in a single operation. The transformation would proceed via an intermolecular SNAr reaction of the dioxides with cyclic diarylmethylpotassium followed by intramolecular SNAr cyclization. This straightforward strategy provides a wide range of spirocyclic diarylfluorenes including unusual ones that are otherwise difficult to synthesize.
Palladium-catalyzed hydroxylation of aryl and heteroaryl halides enabled by the use of a palladacycle precatalyst
Cheung, Chi Wai,Buchwald, Stephen L.
, p. 5351 - 5358 (2014/06/23)
A method for the hydroxylation of aryl and heteroaryl halides, promoted by a catalyst based on a biarylphosphine ligand tBuBrettPhos (L5) and its corresponding palladium precatalyst (1), is described. The reactions allow the cross-coupling of both potassium and cesium hydroxides with (hetero)aryl halides to afford a variety of phenols and hydroxylated heteroarenes in high to excellent yield.
Synthesis and photochromic behaviour under flash photolysis and continuous irradiation of novel 2H-chromenes derived from hydroxydibenzothiophenes
Oliveira, M.Manuel,Moustrou, Corinne,Carvalho, Luis M,Silva, José A.C,Samat, André,Guglielmetti, Robert,Dubest, Roger,Aubard, Jean,Oliveira-Campos, Ana M.F
, p. 1709 - 1718 (2007/10/03)
The synthesis and photochromic properties, under flash photolysis and continuous irradiation, of new 2,2-diphenyl-2H-1-benzopyrans including a dibenzothiophene nucleus are described. Under flash photolysis, all compounds exhibit photochromic behaviour in solution at room temperature, but under continuous irradiation the same was not perceived. Compared to reference compounds, a general bathochromic shift and the existence of two absorption bands in the Vis spectra of the open forms, leading to a boardening in the absorption range, is observed. The heteroannellation effects on the spectrokinetic parameters are variable and depend on the position and geometry of the fused benzothiophene moiety. The effect of electron-withdrawing substituents in C(6) of the 2H-1-benzopyran skeleton, with the benzothiophene nucleus fused at the 7,8 positions, are analyzed.
