1. Department of Chemistry, University of Kansas, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States
2. Nuclear Magnetic Resonance Laboratory, Molecular Structures Group, University of Kansas, 2034 Becker Dr, Lawrence, Kansas 66047, United States
3. Department of Chemistry, University of Memphis, 3744 Walker Avenue, Memphis, Tennessee 38152, United States
4. Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
5. Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109, United States