Spiro compounds have been considered key scaffolds for pharmaceutical applications. Although many synthetic methods exist for monospirocycles, fewer approaches are known for dispirocycles. Here, we report a highly -selective method for constructing a 5/6/5-dispirocyclic structure containing pyrrolidine and γ-lactam rings with various substituents from a series of -arylpropiolamides. The high -selectivity would result from isomerization under thermodynamic control. - and -diastereomers can be in equilibrium, favoring -adducts.
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