The Stereochemistry of the 1,4-Elimination of Thiocyanic Acid from Hex-3-ene-2,5-diyl Dithiocyanates

The elimination of thiocyanic acid from the stereoisomers of the hex-3-ene-2,5-diyl dithiocyanates, <b>4a</b>, <b>4b</b>, <b>6a</b> and <b>6b</b>, in the presence of a strong neutral base in an organic solvent, yields mixtures of the hex-2,4-dien-2-yl thiocyanates <b>9</b>, <b>10</b> and <b>11</b><i>via</i> a preferentially <i>syn</i> process.