The reactions of the anions derived from dithioacetals 1-3 and a-amino nitriles 4 toward pyridinium salts 5 are studied. Depending on the nucleophile used, 2-(dihydropyridylmethyl) indoles 6 and 7, which can be cyclized to tetracyclic methanoazocinindole systems 10 and 11, respectively, or 2-substituted 3-(dihydropyridy1) indoles 8 and 9 are formed.
