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Vol. 83
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C D 1;ig. 1.--Suclear iiiagiietic resollance spectra: Curve A, j-e.~o-chloro-6-c.vo-alllitle (111); c u r w B, 5-exo-chlorci tic;/da-deuterio-G-exo-~~inirle (IV); Curve c, S-e.~o-chloro-6-endo-amide ( V ) ; Curre D, j-exo-chloro-6-exo-deuterio-6cndo-amide (VI).
when a scale n10de14 of the bicyclo [2.1.1]hexane nucleus is examined. Acknowledgments.-The authors are most grateful to Dr. J. iY.Shoolery of Varian Associates for his interest, stimulating discussions and suggestions, as well as to Drs. L. Johnson and N. Bhacca for their kind assistance in obtaining these spectra. The support of this work by the Alfred P. Sloan Foundation and the Kational Science Foundation is acknowledged with pleasure. Simon Guggenheim Foundation Fellow, 1960-19iil. author is must thankful to t h e Department of Chemistry of S t a n f o r d IJniversity for its cordial hospitality during t h e Winter a n d Spring 1901 Quarters. !I) j o h n
'l'iiia
DEPARTMENT O F CHEMISTRY
JERROLD
CORNELL UXIVERSITY Fig. 2.--Sonie approsinlate prc iti ) i i *1iiti--spiii wti1)liiig colist:ints for Iiiryclo[L' I .1]Iiesmies.
iiiore, the cleuteratcd iiiialog (VI) shows reiiiurkablc simplicity. These results, suiiiiiiarizecl ill Fig. 2 , suggest rather extensive iiiteractioiis between a specific pair of protons separated by four single bonds, and smaller interactions between several pairs of adjacent protons. The long-range interaction may be rationalized by assuming fairly extensive overlap between the small lobes of the orbitals directed 180' away from the directions of the ezdo C j and CCI to proton botids (and consequently pointed tonwrtl tach other). This cxplmation appears rtasoiiublt
NEW YORK
ITEIAC.4,
MEINWALD~
ARTHURLEWIS
RECEIVETI APKIL1.5, 1961
THE STEREOCHEMISTRY OF THE ETHYLENEDIAMINETETRAACETATOAQUOFERRATE (111) ION1
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