Structure of 2,5:3,4-dianhydro-D-altritol.

3,6-Dioxabicyclo[3.1.0]hexane-2,4-dimethanol, C6H10O4, M(r) = 146.1, orthorhombic, P2(1)2(1)2(1), a = 7.6209 (2), b = 9.1292 (3), c = 9.6135 (5) A, V = 668.8 (1) A3, Z = 4, Dx = 1.451 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 1.15 cm-1, F(000) = 312, T = 298 K, R = 0.029 for 1280 observations with I greater than 3 sigma(I) (of 1695 unique data). The tetrahydrofuran ring has the envelope conformation, OE, with P of 94.3 degrees and tau m = 24.0 degrees. C atoms deviate from their best plane by +/- 0.0006 (1) to 0.010 (1) A, and the O atom lies 0.331 (1) A from that plane. The epoxide O atom is syn to the tetrahydrofuran O atom. Each hydroxy group is involved in intermolecular hydrogen bonding both as donor and acceptor. The two hydrogen bonds have O...O distances of 2.743 (1) and 2.729 (1) A, and angles about H of 166.3 (12) and 172 (2) degrees, respectively.