An Efficient Synthesis of Dihydrobenzo[c]azepines from Morita-Baylis-Hillman Adducts via Pictet-Spengler Reaction

Various dihydrobenzo[c]azepines were synthesized in good yields via Pictet–Spengler cyclization protocol from tosylamide derivatives of Morita–Baylis–Hillman adducts and 1,3,5‐trioxane. The synthesis was carried out in the presence of easily removable montmorillonite K‐10 in short time in high yields.