Synthesis and complexation of dichalcogenoethers with cyclopropyl backbones, (CH2EMe)2 (E = Se or Te)

The reaction of LiTeMe with C(CH2Br)4 in thf gives (CH2TeMe)2 irrespective of the ratio of reactants, in contrast to the reaction with LiSeMe, which gives either C(CH2SeMe)4 or (CH2SeMe)2 depending upon the reaction conditions. The synthesis and properties of [(CH2TeMe2)2]I2, (CH2TeMeI2)2, [Mn(CO)3Cl{(CH2EMe)2}] (E = Se or Te) and [MCl(η6-p-cymene){(CH2EMe)2}]PF6 (M = Ru or Os) are described. X-ray crystal structures are reported for [(CH2TeMe2)2]I2, [Mn(CO)3Cl{(CH2TeMe)2}], [MCl(η6-p-cymene){(CH2TeMe)2}]PF6 (M = Ru, E = Se or Te and M = Os, E = Se). The effect of the cyclopropyl ring in the ligand backbone is to open up the C–C–C angle within the chelate ring, compared with trimethylene linked analogues. Selenium–carbon bond fission occurs on attempted quaternisation of o-C6H4(CH2SeMe)2 or (CH2SeMe)2 with MeI yielding [Me3Se]I.