Convenient two-step synthesis of highly functionalized benzo-fused 1,4-diazepin-3-ones and 1,5-diazocin-4-ones by sequential Ugi and intramolecular SNAr reactions

- Tri- and tetra substituted 1,4-benzodiazepin-3-ones were prepared in two straightforward steps.
- The described synthetic route uses affordable and readily available building blocks.
- A wide variety of functionalized substituents can be introduced on 1,4-benzodiazepin-3-ones.
- The described approach gives also access to polysubstituted 1,5-benzodiazocin-4-ones.

Benzodiazepinones are an important family of heterocycles with very attractive pharmacological properties and peptidomimetic abilities. We report herein a rapid and efficient two-step synthesis of polysubstituted 1,4-benzodiazepin-3-ones and 1,5-benzodiazocin-4-ones using a multicomponent condensation/cyclization strategy. The approach uses an Ugi four-component reaction to condense readily available Nα-Fmoc-amino acids, amines and isocyanides with a 2-fluorobenzaldehyde derivative followed by a one-pot Fmoc-group removal, intramolecular aromatic nucleophilic substitution for ring closure and side chain deprotection. The described method gives access to benzo-fused 7- and 8-membered rings bearing a wide variety of functionalized substituents and was applied to efficiently prepare tri- and tetrasubstituted 1,4-benzodiazepin-3-ones and 1,5-benzodiazocin-4-ones in high yields in two straightforward steps.

165