Computational, Mechanistic, Organosulfur, and Physical Organic Chemistry
NIH Postdoctoral Fellow
Alexander von Humboldt Fellow
Fulbright-Hays Senior Research Scholar
NIH Postdoctoral Fellow, Yale University
Azaallyl anions and azomethine ylides are being used in cycloadditon reactions and in Michael reactions to synthesize derivatives of substituted piperazines, pyrroles, pyrrolines, and 2-aza-1,4-pentadienes which have shown anticancer activity and anti-AIDS/HIV activity. C-Nucleosides (1), homo-C-nucleosides, exocyclic N-nucleosides, and new heterocycles (2, eq 1) which are potential antitumor and antiviral agents are being synthesized. The stereochemistry, products, and mechanisms of the rearrangement of heterocycles and the oxidation of organosulfur compounds are being investigated.
Computational and experimental aspects of the mechanisms and transition states involved in the cycloaddition and Michael reactions of azaallyl anions and azomethine ylides, in sigmatropic rearrangements, and in the rearrangements of vicinal disulfoxides are under investigation.
Freeman, F.; Bui, A.; Dinh, L.; Hehre, W. J. Dehydrative Cyclocondensation of Hydrogen Thioperoxide and of Alkanesulfenic Acids. J. Phys. Chem. A 2012, 116, 8031-8039.
Freeman, F. Mechanism of the Cysteine Sulfenic Acid O-Sulfenylation of 1,3-Cyclohexanedione. Chem. Commun. 2014, 50, 4102-4104.
Freeman, F.; Adesina, I. T.; La, J. L. ; Lee, J. Y.; Poplawski, A. A. Conformers of Cysteine and Cysteine Sulfenic Acid and Mechanisms of the Reaction of Cysteine Sulfenic Acid with 5,5-Dimethyl-1,3-cyclohexanedione (Dimedone). J. Phys. Chem. B. 2013, 117, 16000-16012.
Freeman, F.; Lau, D. J.; Atitkumar, P. R.; Pavia, P. R.; Willey, J. D. Substituent Effects on Singlet-Triplet Gaps and Mechanisms of 1,2-Rearrangements of 1,3-Oxazol-2-ylidenes to 1,3-Oxazoles J. Phys. Chem. A 2008, 112, 8775-8784.
Freeman, F.; Po, H. N.; Ho, T. S.; Wang, X. Electrochemical Oxidation of 2-Pyrimidinethiols and Theoretical Study of Their Dimers, Disulfides, Sulfenyl Radicals, and Tautomers J. Phys. Chem. A 2008, 112, 1643-1655.
Freeman, F.; Hwang, J. H.; Junge, E. H.; Parmar, P. D.; Ren, Z.; Trinh, J. Conformational Analysis of Cycloheptane, Oxacycloheptane, 1,2-Dioxacycloheptane, 1,3-Dioxacycloheptane, and 1,4-Dioxacycloheptane Int. J. Quantum Chem. 2007, 108, 339-350.
Freeman, F.; Entezam, B.; Gomerooni, F.; Welch, T. S.; Shainyan, B. A. Computational Study of Conformations and of Sulfinyl Oxygen-Induced Pentacoordination at Silicon in 4-Chloro-4-silathiacyclohexane 1-Oxide and 4,4-Dichloro-4-silathiacyclohexane 1-Oxide, J. Organomet. Chem., 2005, 690, 4103-4113.
Freeman, F.; Po, H. N. Dimers of and Tautomerism Between 2-Pyrimidinethiol and 2(1H)-Pyrimidinethione: A Density Functional Theory (DFT) Study, J. Physical Chem. A, 2006, 110, 7904-7912.
Freeman, F.; Bathala, R. M.; Huang, A. C.; Jackson, T. K.; Lopez-Mercado, A. Z.; Phung, S.; Suh, J.; Valenica, Jr., D. O. [2,3]-Sigmatropic Rearrangements of Hydrogen and Alkyl 3-Propenyl Sulfoxides: A Computational Study, Int. J. Quantum Chem. 2006, 106, 2390-2397.
Relative Energies of Conformations and Sulfinyl Oxygen-Induced Pentacoordination at Silicon in 4-Bromo-, and 4,4-Dibromo-4-silathiacyclohexane 1-Oxide, Int. J. Quantum Chem., 2005, 105, 313-324.
Freeman, F.; Fang, C.; Hoang, D. V.; Trinh, K. M. Relative Energies of Conformations of Stannacyclohexane, 1-Methylstannacyclohexane and 1,1-Dimethylstannacyclohexane: Effect of Theoretical Levels Int. J. Quantum Chem., 2005, 105, 416-428.
Freeman, F.; Cha, C.; Fang, C.; Huang, A. C.; Hwang, J. H.; Louie, P. L.; Shainyan, B. A. Relative Energies, Stereoelectronic Interactions and Conformational Interconversions in Silathiacyclohexanes J. Phys. Org. Chem. 2005, 18, 35-48.
Freeman, F.; Dang, P.; Huang, A. C.; Mack, A.; Wald, K. 1,3-Dipolar Cycloaddition of Azomethine Ylide with Ethene and 2-Butene: A Computational Study Tetrahedron Lett., 2005, 46, 1993-1995.
Shainyan, B. A.; Kirpichenko, S. V.; Freeman, F. Sila-Pummerer Rearrangement of Cyclic Sulfoxides: Computational Study of the Mechanism, J. Am. Chem. Soc., 2004, 126, 11456-11457.
Freeman, F.; Kasner, M. L.; Hehre, W. J. An Ab Initio Molecular Orbital Theory and Density Functional Theory Study of Conformers of Tetrahydro-2H-pyran, J. Phys. Chem. A 2001, 105, 10123-10132.
"Kinetics of the Base-Catalyzed Permanganate Oxidation of Benzaldehyde," Wiberg, K. B.; Freeman, F. J. Org. Chem. 2000, 65, 573-576.
08/14/2019