Dibenzo dioxepines

It has been reported that 1 l//-dibenzo[h,< ][ ,4]dioxepin-l 1-one (dep-sidone) (243) undergoes photochemical decarboxylation and yields dibenzo-furan (59%) on irradiation with a high-pressure mercury lamp. The authors do not report whether the irradiation was conducted through silica or borosilicate glass. 

Because of the importance of the biphenyl scaffold, as a structure of pharmaceutical and active therapeutic compounds, the mass spectrometric behavior of a series of 6,6-disubstituted dibenzo[r//][l,3]dioxepins 36 has been studied. The electron ionization-induced fragmentation patterns were discussed based on use of labeled compounds, accurate mass measurements, and collisionally induced dissociation experiments using an ion trap <2006JMP577>. 

The organometallic 37 bearing a dibenzo-fused dioxepin ring has been characterized by MALDI-TOF mass spectrometry using a 2-[(2-E)-3-(/rz -butylphenyl)-2-methylprop-2-enylidene]malononitrile matrix <2006ANC199>. 

Novel dibenzo[d,f [I,3]dioxepines have been prepared from 2,2 -biphenol <94TL9327>. Thus reaction with 2-chloroacrylonitrile fords... 

Lichen depsidones (1 lH-dibenzo[f),e]dioxepin-ll-ones) as potential novel pharmacologically active compounds 12MR0178. 

Synthesis, reactions, and conformations of dibenzo[d [l,3]dioxepine derivatives 12JHC1. 

Hydroxy-4-formylphenoxy) benzoic acid in ether containing pyridine treated with SOGlg in ether, and stirred 3 days ll-oxo-llH-dibenzo[b,e] [l,4]dioxepin-... 

Gevorgyan and co-workers reported a mild, practical, and efficient method for the synthesis of symmetrical and unsymmetrical o-biphenols, o-phenol-naphthols, and o-binaphthols. The method involves a Pd-catalyzed intramolecular C-H aiylation of unsymmetrical bis-aiylo)q silanes to give the seven-membered oxasilacycles, which, via a consecutive routine TBAF deprotection, furnish valuable unsymmetrical o-biphenols and o-binaphthols. In 2013, the intramolecular cyclization of di-ortAo-bromoaiylo q acetal and o/tfto-bromoaiylo y acetal to the corresponding dibenzo[l,3]dioxepines was developed. ... 

C3i,H28Cl80a, 5,6,7,8-Tetrachloro-lO-cyclohexylidene-3a,10-dihydro-benzo[b]-cyclopenta[e](1,4)dioxepine dimer, 42B, 149 C3 6H oN2Na20i4, Dibenzo-24-crown-8-bis(M"0-nitrophenolato)disodium, 41B, 393... 

The depsidones are based on the 1 l/f-dibenzo[Z ,e] [l,4]dioxepin-l 1-one ring system and are numbered systematically as in formula (281) which will be adhered to in this discussion. For convenience the benzenoid rings are desigjiated as A and B. Many workers in this field use the numbering system in formula (282) which emphasizes the relationship of depsidones to the /7flm-depsides. 

Lele, S. R., and B. D. Hosangadi Studies in Photoinduced Reactions on Depsidones Synthesis of Dibenzofuran from 11 H-Dibenzo[b,e] [l,4]dioxepin-ll-one. Indian J. Chem. 16B, 415 (1978). 

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