The enamine derived from tryptamine and ethyl ethoxymethylenemalonate, on treatment with trifluoroacetic acid or boron trifluoride, is converted into 3,4-dihydro-β-carboline.
The edge sharing bioctahedral anions [M2Br10]2-, M = Os, Re, have been prepared from [MBr6]2 in trifluoroacetic acid containing Hg2+ ions at room temperature. Heating the solid decabromodirhenate(IV) with Hg in a vacuum at 100 °C affords the octabromodirhenate(III) with a quadruple bond between the Re atoms in quantitative yields.
Frontispiece: A Tandem In Situ Peptide Cyclization through Trifluoroacetic Acid Cleavage
