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In the crystal structure of the title compound [systematic name fluoren-9-ylmethyl N-(1-carboxy-2-methylbutyl)carbamate], C21H23NO4, the molecular plane of the O=C—NH—Cα unit is slightly pyramidalized. The N atom deviates from the basal plane by 0.2086 (12) Å. The O=C—N—Cα torsion angle is −17.2 (2)°, and the C—N and O=C bond lengths are 1.3675 (17) and 1.2122 (17) Å, respectively. Apparently the character of the sp2 hybrids of the molecular plane is, to some extent, reduced. The crystal structure exhibits two intermolecular hydrogen bonds (O—H...O and N—H...O), in which the hydroxy O atom acts as a donor to the carbonyl group and an acceptor of the amide group, respectively.