Organoiron complexes in organic synthesis. Part 2. Conformational and steric effects of methyl substituents in tricarbonyliron derivatives of bicyclo[4.4.0]decadienes

The reactions of cyanide and dimethyl sodiomalonate with 7- and 10-methyl-substituted derivatives of tricarbonyl-[1,3–6-η-4-methoxybicyclo[4.4.0]deca-3,5-dienylium]iron hexafluorophosphate have been studied. The presence of exo-methyl groups suppresses the addition of nucleophile to the angular terminus, C-1, and endo-methyl groups cause the formation of mixtures of angularly and non-angularly substituted products.