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A pseudopericyclic transition state (TS) involving nonlinear H transfer is proposed for the superene reaction (eq 1), characterized by a temperature-independent isotope effect (^h/^d = 2.863). Ancillary evidence for rapid, reversible formation of a four-membered cyclic charge-transfer complex is also presented to account for the observed regio-and stereoselectivity of the reaction.

The ene reactions of sulfur diimides TosNSNAr (1; Ar = C6H6,4-02NC6H4, and CeF6) with 2-methyl-2-butene (2) have been investigated. The products undergo a [2,3] sigmatropic rearrangement. The structures of these rearranged products have been determined. Taking into account the regioselectivities shown by compounds 1 in related cycloadditions, the results suggest that the ArN=S bond is exclusively involved in the ene process. This bond has been proven to be Z configurated for Ar = C6F6 by an X-ray structure determination, whereas the TosN=S bond possesses the E configuration. Steric shielding of the (E)-N=S bond by the aromatic system attached to the (Z)-N=S bond is deemed to be important in determining the regioselectivity, especially if the H abstraction is to be executed by the lone electron pair of the nitrogen atom.

Bis‐methoxy carbonyl‐schwefeldiimid (I) reagiert mit zahlreichen Olefinen (II) zu den Diaminosulfanen (III), die über die Carbamate (IV) zu entsprechenden Allylaminen (V) hydrolysiert werden oder mit Lithiumalanat zu den Methylverbindungen (VI) führen.