The Crystal Structure of 3-(10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene)-1-ethy1-2-methylpyrrolidine Hydrobromide

Abstract

Abstract The crystal structure of 3-(10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene)-1-ethyl-2-methllpyrrolidine hydrobromide, C22H26NBr, has been determined. The crystal is monoclinic with space group P21⁄a; the unit-cell dimensions are: a=30.16, b=18.78, c=7.048 Å, β=90.53°. The asymmetric unit contains two molecules. The intensities were estimated visually from the multiple-film equi-inclination Weissenberg photographs. The structure was solved by the heavy atom method. The atomic parameters were refined by the blockdiagonal least-squares method, and final R index was reduced to 0.147. It is concluded that the overall geometry of the two independent molecules is similar in every detail The pyrrolidine ring is puckered. The 10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-ylidene part consists of three planes. The dihedral angles between the planes are 63° for the benzene planes I and II, 59° for the benzene plane I and the ylidene plane, and 76° for the benzene plane II and the ylidene plane.