Acknowledgment.-The authors are grateful to Dr. James W. Patton for obtaining many of the nmr spectra and to Dr. S. Seltzer of Brookhaven National Laboratory for the A-60 spectrum. We are indebted to Professor J. D. Roberts, Dr. F. C. Nachod, and Dr. Paul C. Lauterbur for helpful criticism and advice. ... EDWARD hl. KOSOWER'~ .4ND THEODORE s. SORENSES1bic ... Department of Chemistry, The University of Wisconsin, hfadison, Wisconsin Received July 2, 1962
