Butallyl­onal 1,4-dioxane hemisolvate

The asymmetric unit of the title compound [systematic name: 5-(1-bromo­prop-2-en-1-yl)-5-sec-butyl­pyrimidine-2,4,6-trione 1,4-dioxane hemisolvate], C(11)H(15)BrN(2)O(3)·0.5C(4)H(8)O(2), contains one half-mol­ecule of 1,4-dioxane and one mol­ecule of butallyl­onal, with an almost planar barbiturate ring [largest deviation from the mean plane = 0.049 (5) Å]. The centrosymmetric dioxane mol­ecule adopts a nearly ideal chair conformation. The barbiturate mol­ecules are linked together by an N—H⋯O hydrogen bond, giving a single-stranded chain. Additionally, each dioxane mol­ecule acts as a bridge between two anti­parallel strands of hydrogen-bonded barbiturate mol­ecules via two hydrogen bonds, N—H⋯O(dioxane)O⋯H—N. Thus, a ladder structure is obtained, with the connected barbiturate mol­ecules forming the ‘stiles’ and the bridging dioxane mol­ecules the ‘rungs’.