Synthesis and crystal structure determination of two dispiro compounds from laboratory x‐ray powder diffraction data

The crystal structures of the dispiro compounds 1,3,4,8,10,11‐Hexaphenyl‐13‐methyl‐1,2,8,9,13‐pentaazadispiro[4.1.4.3]tetradeca‐2,9‐dien‐6‐one ( 3a ) and 4,11‐Bis(4‐methoxyphenyl)‐13‐methyl‐1,3,8,10‐tetraphenyl‐1,2,8,9,13‐pentaazadispiro‐[4.1.4.3]tetradeca‐2,9‐dien‐6‐one ( 3b ) have been determined at room temperature from X‐ray powder diffraction data using the method of simulated annealing as implemented in the programs DASH and TOPAS. Subsequent Rietveld refinements using the data collected to 1.5 Å resolution yielded R‐Bragg values of 2.2% for ( 3a ) and 3.7% for ( 3b ). It was found, that both compounds crystallize in the monoclinc space group P 2₁/n with lattice parameters of a = 17.1656(5) Å, b =13.8128(3) Å, c = 16.1016(5) Å, and β = 103.7330(2)° for ( 3a ) and a = 17.2529(8) Å, b = 13.8729(5) Å, c =16.1287(10) Å, and β = 103.6910(3)° for ( 3b ). Both compounds exhibit a distorted hexagonal close type of packing (hcp) of the molecular centers of gravity. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)