The effect of ortho substituents NH,, OCH,, CH,, C1 and NO, on the fragmentation of five symmetrically and five unsymmetrically 2,2'-disubstituted stilbenes under electron impact was investigated. The fragmentation patterns deduced were supported by metastable transitions in the first and second field free regions and by exact mass measurements of prominent ions. In general, the fragmentation was found to be in accord with that of stilbene and the corresponding monosubstituted stilbenes. There are, however, some deviations from the general fragmentation scheme caused by direct through-space interactions of the ortho, ortho' substituents with concomitant loss of neutral fragments. It is supposed that the formation of 7-membered cyclic or heterocyclic ions is the result of such through-space reactions.

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Several new N‐allyl‐N‐(5‐substituted)‐2‐furfuryl‐p)‐toluidines IIIa‐e with Cl, Br, I, NO2 or CH3O groups in position 5 of the furan nucleus were prepared by allylation of the corresponding secondary furfurylaryl‐amines. Both, electron withdrawing and releasing substituents enhanced the yield of intramolecular [4+2] cycloaddition.

The preparation of substituted N‐arylisoindolines 3 from simple furan derivatives 1 is reported. Oxatricycloadducts 2, readily accessible by intramolecular Diels‐Alder reaction are susceptible to acidic reagents yielding aromatized products 3 by a ring‐opening reaction via intermediate carbocation.

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