| Summary: | An efficient and easy approach to the synthesis of novel racemic planar-chiral 3,4-dihydroferroceno[<i>c</i>]pyridines and 1<i>H</i>-ferroceno[<i>c</i>]pyrroles via the intramolecular Ritter reaction of 2-ferrocenyl-3,3-dimethylbutan-2-ol with nitriles and thiocyanates in the presence of MeSO<sub>3</sub>H was developed. Aromatic and aliphatic nitriles, phenylacetonitriles, and <i>β</i>-oxonitriles produced exclusively 3,4-dihydroferroceno[<i>c</i>]pyridines. The condensation of 2-ferrocenyl-3,3-dimethylbutan-2-ol with various thiocyanates, including alkyl thiocyanates, benzyl thiocyanate, and ethyl 2-thiocyanatoacetate, yielded not only 3,4-dihydroferroceno[<i>c</i>]pyridines but also 1<i>H</i>-ferroceno[<i>c</i>]pyrroles. The selectivity of these reactions depended on the temperature and the order of addition. The size of substituents at the <i>α</i>-position to the sulfur atom of thiocyanates also had a significant effect on the distribution of products.
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