1.3- Benzodithioles, 2-alkoxy

Thermal decomposition of the sodium salt of the tosylhydrazone (346) at 180 °C produces the dibenzotetrathiafulvalene (347) in 51% yield (74LA403). Also the 2-alkoxy-l,3-benzodithioles (312) decompose thermally at 200 °C to give (347) in 22-55% yield (75S168). 

Alkoxy-l, 3-benzodithioles (146) react in acetic acid at room temperature with aromatic compounds having strong electron-donor substituents to give 2-aryl derivatives in good yields. The dithiole probably dissociates into alkoxide ion and 1,3-benzodithiolium which acts as electrophilic reagent with aromatic compounds. ... 

Alkoxy-l,3-benzodithioles (38) can be pyrolyzed (200°C, 2 h) into a mixture of the corresponding benzo-TTF (39) and the spiro-compound (40) (Equation (3)) <75S168>. 

Alternatively, dibenzotetrathiafulvalene (392) has been obtained in 51% yield by the pyrolysis of either 2-imino-l,3-benzodithiol in the presence of one equivalent of sodium methoxide in diglyme at 180°C <74LA403> or by pyrolysis of suitable 2-alkoxy-l,3-benzothioles (393) at 190-200°C... 

Alkoxy-l, 3-benzodithiole, die in einfacher Weise aus 2-Diazo-benzoesaure und Schwefel-kohlenstoff in Gegenwart von Alkanol erhalten werden377, setzen sich mit prim., sek. oder tert. Alkanthiolen sowie Thiophenolen in Essigsaure tiber 1,3-Dithiolanium-Ionen auBer-ordentlich rasch zu 2-Alkyl(Aryl)thio-l,3-benzodithiolen um378 ... 

Alkoxy-l, 3-benzodithioles (1). Carbon disulfide undergoes 1,3-dipolar cycloaddition to benzyne [generated from benzenediazonium-2-carboxylate (1,46)] to give 1,3-benzodithiole-2-carbene (a). This carbene reacts with alcohols to form (1) in 35-50% yields. The reaction can be carried out in one-step from anthranHic acid, since carbon disulfide is more reactive than alcohols toward benzyne. ... 

Substituted-l,3-benzodithioles. These useful aldehyde derivatives (2) can be prepared easily by reaction of Grignard reagents with 2-alkoxy-l,3-benzo-... 

Scheme 8 depicts a convenient synthesis of 2-substituted-l,3-benzodithioles (protected aldehydes) from a 2-alkoxy-l,3-benzodithiole, itself prepared directly from anthranilic acid. Compounds RCH(SMe)2, also protected aldehydes, are available by reaction of RMgX with MeSOCH2SMe. 

Reaction of benzynes with carbon disulfide 2-Alkoxy-l,3-benzodithioles... 

The chemistry of 2-alkoxy-l,3-benzodithioles has been reviewed. A new route for the reduction of carboxylic acid derivatives is provided by their conversion into... 

Thioacetals can exert dual purpose activity. In addition to their use as acyl carbanion equivalents, they can often be used as electrophilic species. Thus, 1,3-dithian is chlorinated between the two S atoms with iV-chlorosuccinimide, and the product is susceptible to attack by nucleophiles (PhSH, imidazole). Readily available 2-alkoxy-l,3-benzodithioles are also attacked by active methylene compounds such as )8-dicarbonyl compounds or ethyl cyanoacetate, to give excellent yields of the substitutioq products. The utility of 1,3-benzodithioles is further... 

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