2‐Cyanoaziridine

Abstract

Such reasoning provides a qualitative explanation of the varying A I E values of the 1,fdithia compounds (Table 2) on the basis of Figure 2.Fig. 2. Qualitative M O schemes for ns/n, and ns:u interactions in 1,3-dithia compounds.EHT calculations on the open-chain compound 2,4dithiapentane in the C,, conformation show the n, MO to lie above the n-MO whose symmetry properties (asymmetric with regard to both mirror planes) rule out admixture of cCH, orbitals. In the 1,3-dithiane (C,) and in bis(thioph0sgene) (DZh), however, combinations with molecular orbitals 0 , are symmetry allowed for both n, and n-so that the sequence IE(n-)<lE(n+) is retained. Similar differences between the lowest PE ionization potentials are observed (Table 2) in IP-dithia compoynds, in spite of the large S . . -S distance (d,,,.,>3.5A[91); this can be interpreted in terms of predominating "through bond" interaction['].