1-tert-butyl-9-methoxy-4-methyl-1,2,3,4-tetrahydro-2-azafluoren-3-one, a novel fluorenone

The title compound, C18H23NO2, is the final compound in the reaction betwee n an ethynyl Fischer carbene and a 2-azadiene. The reaction proceeds to the stereoselective formation of a 2-azafluorenone. The structure determinatio n reveals hydrogen bonding linking the carbonyl O atom and the H atom attac hed to the N atoms of symmetry-related molecules. As a result, the structur e packing is composed of dimers connected by two hydrogen bonds. These hydr ogen bonds show a similar geometry to those found between pairs of bases in DNA, and the structure itself resembles some synthetic inhibitors of DNA t ranscription.