STRUCTURE OF A CHALCONE

Abstract

1-(7-Hydroxy-2,2-dimethylchroman-6-yl)-3-phenyl-2-propen-1-one, C20H20O3, M(r) = 308.38, P2(1)/a, a = 12.002 (2), b = 11.013 (2), c = 12.652 (3) angstrom, beta = 106.24 (3)-degrees, V = 1605.6 angstrom3, Z = 4, D(m) = 1.26 (2), D(x) = 1.275 Mg m-3, lambda(Mo Kalpha) = 0.71069 angstrom, mu = 0.075 mm-1, F(000) = 656, T = 293 K, R = 0.037, wR = 0.034 for 892 reflections with I > 3sigma(I). There is an internal hydrogen bond O-H ... O between the carbonyl O atom in the cinnamoyl group and the hydroxy group of the chroman moiety. The conformational analysis shows that the phenyl ring is trans with respect to the double bond linking it with the chroman group. The pyran ring is in the prevalent half-chair conformation.