4.7- Dihydro-2-phenyl-1,3-dioxepins

C11H1202 4,7-dihydro-2-phenyl-1,3-dioxepin 2568-24-3 533.71 47.132 2 21982 C11H13N02 5-methoxyt ryptophol 712-09-4 576.15 51.247 2... 

Chlorine and bromine add normally to the double bond in (256) and the dibromo compound can be mono-dehydrobrominated using sodium methoxide in methanol to give a mixture of 5-bromo-4,7-dihydro-l,3-dioxepin and 5-bromo-4,5-dihydro-l,3-dioxepin (which is converted in situ to the 5-methoxy derivative). More interestingly it can be fully dehydrobrominated using HMPA at 140 °C to give the fully unsaturated 2H- 1,3-dioxepin (261) (76TL2113). This is the only known route to this compound. It gives a Diels-Alder adduct with 4-phenyl-l,2,4-triazoline-2,5-dione in 95% yield and on UV irradiation it isomerizes to (262). 

Dioxepin 2-(4-Nitro-phenyl)-4,7-dihydro- E14a/1, 250 (R-CHO/ Diol)... 

In the ROMP of cyclooctadiene (Mi) with 4,7-dihydro-2-phenyl-l,3-dioxepin (M2) catalyzed by Ru(=CHR)(Cl)2(PCy3)2, where R = CH=CPh2 or Ph, M2 is about half as reactive as Mi. By using a small proportion of M2, one can produce a polymer of Mi containing occasional M2 units, which may be broken by hydrolysis to yield 1,4-hydroxytelechelic polybutadiene M /M 1.2) (Fraser 1995b). 

Two types of benzoannelated ethers containing a 1,4-dioxepane moiety are known 3,4-dihydro-2//-l,5-benzodioxepin (21), and 2,3-dihydro-5//-l,4-dioxepin (22). 3,4-Dihydro-2/f-l,5-benzo-dioxepin (21) can be prepared either from (20) or (23). Derivative (25) has been obtained by the reaction of 2-hydroxy-2,3-dihydro-2-phenyl-l,4-benzodioxin (24) with phenacylbromide <87UKZ614>, and compounds (26) were isolated as by-products together with isomeric 2-substituted 2,3-dihydro-2-hydroxymethyl-l,4-benzodioxins from the reaction of a-(2-hydroxyphenoxy)-alkylketones and dimethylsulfoxonium methylide <88JHC943>. 

Compounds (141) have been tested for antimicrobial activity. 4-Phenyl-3,4-dihydro-l,5-dioxepin-2-one undergoes ring fission on treatment with LDA to afford catechol monocinnamate <94MI 912-... 

Other than these polymers, some specific systems such as a series of poly(3,4-alkylenedioxythiophene)s have also been studied by Reynolds group, including EEX)T, 2-methyl-2,3-dihydrothieno[3,4-(>][l,4] dioxine (EDOT-Me), 2-tetradecyl-2,3-dihydrothieno[3,4-6] [l,4]dioxine (EEX)T-Ci4H29), 2-phenyl-2,3-dihydrothieno[3,4-Z>] [l,4]dioxine (EEX)T-Ph), 3,4-dihydro-2//-thieno[3,4-6] [l,4]dioxepine (ProDOT),... 

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