Solvent-free conditions cycloadduct synthesis

Ball milling of stoichiometric amounts of two solid reagents, Diels-Alder partners led to synthesis of silicon-containing heterocyclic product. Cyclic diene 1,1-dimethyl-2,3,4,5-tetraphenylsilole 1 reacts with iV-methyl maleimide in solid-state milling to afford the enrfo-Diels-Alder cycloadduct 3 stereospeciflcally (Scheme 5.1) [1]. Notably, transfer of reaction conditions from solution chemistry to solvent-free procedure does not have any effect on stereochemical outcome [2]. 

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