Crystal and molecular structures of two N-carboxy anhydrides of Cα,α-disubstituted glycines*

Abstract

The crystal and molecular structures of 4,4-diethyl-oxazolidine-2,5-dione (1) and 3-(2'-nitrophenylsulfenyl)-4,4-di-n-propyl-oxazolidine-2,5-dione (2) have been determined by X-ray diffraction. The compounds possess the following parameters: (1) monoclinic, space group P21/n (No. 14), a = 8.931(1) Å, b = 11.749(2) Å, c = 7.867(1) Å, β = 98.0(2)°, and Z = 4; (2) triclinic, space group P[unk] (No. 2), a = 12.187(2) Å, b = 9.588(1) Å, c = 7.681(1) Å, α = 72.9(2)°, β = 73.0(2)°, γ = 84.9(2)°, Z = 2. The crystal structures were solved by direct methods. The least-squares refinements led to R values of 0.040 and 0.039 for 1144 and 2068 reflections with F≥7σ(F) for (1) and (2), respectively. The molecules of (1) are linked by intermolecular N1–H1… O2 = C2 hydrogen bonds along the y direction. The difference observed between the C1–O1 and C2–O1 distances within the heterocyclic moiety of (1) is not found in (2).