Structure of sp-9-hydroxy-9-pivaloylfluorene, product of base-catalyzed autoxidation of ap-9-pivaloylfluorene.
1-(9-Hydroxyfluoren-9-yl)-2,2-dimethyl-1-propanone, C18H18O2, M(r) = 266.34, orthorhombic, Pbcn, a = 18.917 (10), b = 11.843 (8), c = 13.177 (7) A, V = 2952 (5) A3, Z = 8, Dx = 1.198 g cm-3, lambda(Mo K alpha) = 0.71069 A, mu = 0.72 cm-1, F(000) = 1136, T = 296 K, R = 0.044 for 1042 unique observed reflections. Conversion of ap-9-pivaloylfluorene, ap-(I), into lithiated (I)-9-anion followed by the addition of MeOH, then H2O, led to unexpected hydroxylation to provide 20-40% of sp-9-hydroxy-9-pivaloyfluorene, sp-(II), and 60-80% recovery of ap-(I). The singular sp conformation of (II) in solution suggested by NMR was confirmed in the crystalline state by X-ray diffraction which showed the O(1)-C(9)-C(10)-O(2) torsion angle approximately 0 degrees and the C(10) = O(2)...H(9)-O(1) non-bonding distance 1.95 (4) A, suggesting strong intramolecular hydrogen bonding in this conformation.
Meyers
C Y
CY
Department of Chemistry, Southern Illinois University, Carbondale 62901.
Tunnell
J L
JL
Robinson
P D
PD
Hua
D H
DH
Saha
S
S
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003460:Crystallization; D005449:Fluorenes / Q000737:chemistry*; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D015394:Molecular Structure; D010084:Oxidation-Reduction; D014961:X-Ray Diffraction
D005449:Fluorenes; C078298:9-hydroxy-9-pivaloylfluorene