ROLE OF HYDROGEN-BONDING IN DETERMINING THE CRYSTAL-STRUCTURES OF THEADDUCTS BETWEEN ACETONE AND UREA DERIVATIVES

The adducts obtained by the reaction between three molecules of aceton e and two molecules of urea or 1-methylurea form different hydrogen bo nding patterns in the solid. The patterns are determined by the number of proton donors and proton acceptors available for the hydrogen bond formation. The adduct between acetone and urea crystallizes with diff erent solvent molecules. When crystallized from water, it forms a thre e-dimensional network, where the water molecules are arranged in an in finite sheet made up of hydrogen bonded four-, six-, and eight-membere d rings that link layers of the organic compound by hydrogen bonds. Wh en crystallized from dimethyl sulfoxide (DMSO) both water and DMSO mol ecules participate in an infinite two-dimensional hydrogen bonding net work.