Structure of methyl 5-phenyl-2-propionyl-3-pyrrolecarboxylate.

C15H15NO3, Mr = 257.4, monoclinic, P2(1)/n, a = 10.070 (2), b = 5.335 (3), c = 24.23 (1) A, beta = 91.60 (3) degrees, V = 1301 (2) A3, Z = 4, Dm (flotation) = 1.312 (3), Dx = 1.314 g cm-3, Cu K alpha (lambda = 1.5418 A), mu = 6.64 cm-1, F(000) = 544, T = 295 K, final R(F) = 0.037, wR = 0.035 for 850 significant reflections, I greater than or equal to 2.5 sigma(I). The phenyl ring and the pyrrole ring are planar, and the dihedral angle between them is 18.6 degrees. The nitrogen of the pyrrole ring exhibits N-H tautomerism and forms N-H...O type hydrogen bonds with the screw related carbonyl oxygen. In the unit cell the molecules form dimers across the centres of inversion and infinite spirals across the screw axis.