Thiophen-fused Tropylium Ions and Related Compounds

Thiophen-fused Tropylium Ions and Related Compounds.— The reaction of some thieno-tropones such as (241) with dimethylsulphoxonium methylide gave cyclopropane derivatives (242). The reaction of (241) with electrophilic reagents has been studied. The synthesis of compounds of type (241) has been modified 

6 Thiophens Fused to FiTe-membered Aromatic Heterocyclic Rings 

Thiophen-fused Tropylium Ions and Related Compounds.— Interest in thiophen-fused tropylium ions is continuing. Bromination of (364) with bromine in CCh gave the tribromo-derivative (365), whereas phenyl trimethylammonium tribromide only dibrominated a to the carbonyl group. Dehydrobromination of the latter gave the thienotropones (366) in high 

6 Thiophens Fused to Five-membered Aromatic Heterocydic Rings 

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