A mild and one-step synthesis of 2,8-dioxabicyclo [3.3.1] nonane derivatives via classical Knoevenagel condensation

Utilizing simple and readily available 2-hydroxy benzaldehydes and 1,3-diketones or 1,3-cyclohexanediones as raw materials, complex 2,8-dioxabicyclo [3.3.1] nonane derivatives were synthesized in one-step via classical Knoevenagel condensation. The reaction was simply conducted under solvent-free and mild conditions, which showed good tolerance to a variety of functional groups. This atom-economical approach delivers an attractive synthetic protocol for 2,8-dioxabicyclo [3.3.1] nonane derivatives.