Benzodithiepin system

Three new spirans, including 131 and 132, incorporating a 1,5-benzodithiepin system have been synthesised from methyl benzynes. The structure of 131 was confirmed by X-ray crystallography, and the seven-membered ring was shown to have a chair conformation and the five-membered ring an envelope conformation . 

The analogous l,5-dihydro-37/-2,4-benzodithiepin system can be prepared by the reaction of 1,2-benzenedimethanethiol with either methylene iodide in the presence of base or with aldehydes or ketones in the presence of acid. 

Reaction of 1,2-benzenedimethanol 333 with aldehydes or related compounds gives l,5-dihydro-3//-2,4-benzodiox-epins 334 as exemplified in Scheme 180 <2001TL3183, CHEC-III(13.11.11.2)361>. The analogous benzodithiepin system 336 can be prepared by the reaction of 1,2-benzenedimethanethiol with methylene iodide in the presence of base or from the dibromide 335 and CS2 as shown in Scheme 181 <20000L1133, CHEC-III(13.11.9.4)356>. 

The influence of structural features of benzodioxepine and benzodithiepine derivatives on rat brain benzodiazepine receptors has been studied <1996MSR589>. A group at Givaudan has synthesized and studied the conception, characterization, and correlation of new marine odorants based on the benzo[A][l,4]dioxepinone system <2003EJO3735>. 1,4-Dithiapane was among a data set of 101 hetero sulfamate sodium salts that was tested as potential sweeteners in a structure-taste relationship study <2000J(P2)1369>. 

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