Oxidative Cycloaddition of Thiophenophanes – [n](2.5)Parathiophenophane (n = 8,10-12,14), [8](2,4)Metathiophenophane and [2.2](2,5)Parametathiophenophane

The oxidative cycloaddition of 3,4-dibromo-[n](2,5)thiophenophanes 12b–e and (2,4)[8]thiophenophane 16 with dienophiles gave stereoselectively OS-bridged cycloadducts 18, 19 and 24. The X-ray analysis of cycloadduct 18a shows it to have a rigid conformation. The molecules can be regarded as a new series of paddlanes. Under the same oxidative conditions, 3,4-dibromo-[8](2,5)thiophenophane (12a) gave the two dimers 29 and 30. The results of the X-ray analysis of 29 are discussed.