Base-Promoted Tandem Synthesis of 3,4-Dihydroisoquinolones

Using benzaldehydes, NaN(SiMe3)2, and N-acylpyr-roles, an operationally simple tandem method to produce a wide array of 3,4-dihydroisoquinolones is presented (37 examples, yields up to 98%). A unique feature of this method stems from the sequential aminobenzylation of aldehydes and transamidation of the corresponding N-(trimethylsilyl)imines in one pot. In this process, three new bonds are generated (one C-C and two C-N bonds). R1 O R2 O 3 equiv NaN(SiMe3)2 H Ar2 1,4-dioxane, 100 degrees C center dot 3 bonds formed center dot oxidant-free center dot broad scope R2 R1 O NH Arz 37 examples up to 98% yield