Crystal and molecular structure of 2,4-di-O-methyl α-D-galactopyranose monohydrate
Abstract
The crystal structure of the title compound (I) has been determined from photographic data, solved by direct methods and refined by full-matrix least-squares techniques to a final R of 0·095 for 1267 reflections. Crystals are orthorhombic, space group P212121 with Z= 4 in a unit cell of dimensions a= 1172(2), b= 1895(3), c= 478(1) pm. Bond lengths and angles are as expected but the two methyl ether substituents have unusual conformations, being eclipsed with the neighbouring C–H bonds. There are three systems of hydrogen bonds, but the axial ether oxygen at C(4) is not involved in any of them.