The structure of a cyclodimer from reaction of 7-methoxy-1,2-dihydronaphthalene with sodium and ethylenediamine. A comparison of bond distances and angles in two molecules

Abstract

6,6 a, 7,12,13, 5 ] cyclohepta [ 1,2-a] n aphth alene, C22H240 z, is a cyclodimerized product obtained from reaction of 7-methoxy-l,2-dihydronaphthalene with sodium and ethylenediamine. The preparation, isolation, and spectral data of this dimer are described.Crystals of the compound are monoclinic, space group P2,/c. The cell dimensions are a = 26.643 (9), b = 8. 165 (3), c = 16.226 (5) A and/~ = 107.56 (2) °. The structure was determined by direct methods and refined with least-squares calculations on 6372 data collected at -160°C. The final R value is 0-060. The asymmetric unit contains two independent molecules which show good agreement of distances for corresponding bonds. It is concluded that the standard deviations calculated from the inverse of the least-squares matrix are not underestimated.