Thiacrown Compounds with 1,2-Dicyano-1,2-dithioethene Units

S2On,1-Coronands containing one 1 ,Zdicyano- 1 ,Zdithioethene unit a-2(n= 1). 3(n=2), 4(n=3)) and macrocyclic tetrathioethers containing two 1 ,Zdicyano- 1 ,Zdithioethene units bridged by propylene(6). butyleneC8). pentyleneo or hexylenew were synthesized by the reaction of (Z)-disodium- 1 ,Zdicyanoethene-1,2-dithiolate with oligoethylene glycol dichlorides and a,@'- dibromoalkanes, respectively. The @)-isomer of macrocycle 2 is the first example of an S/O-coronand with planar chirality. The enantiomers were separated by capillary gas chromatography with modified P-cyclodexain as stationary phase. Unsaturated dithia(l2)crown-4 is a selective extracting agent for PdCI2. In the solid state the unsaturated tetrathia( 14lcrown-4 6 and tetrathia( 16lcrown-4 8 adopt "chair-like'' conformations. Each of four sulfur atoms of both macrocyclic tetrathiaethers direct one lone electron pair toward the hole of the macrocycle.