Wikipedia
Benzodioxan
The benzodioxans are a group of isomeric chemical compounds with the molecular formula CHO. There are three isomers of benzodioxan, as the second atom of oxygen of the dioxane can be in a second, third or fourth position : 1,2-dioxane, 1,3-dioxane and 1,4-dioxane, which respectively give 1,2-benzodioxan, 1,3-benzodioxan and 1,4-benzodioxan.