127107-06-6Relevant articles and documents
Anomalous Shielding and Hidden Partner Chemical Exchange in the (1)H NMR Spectra of the Bisurethane Diazetidines, the 1,2-Diaryl-3,5-dialkyl-6,7-dialkoxycarbonyl-4-oxo-6,7-diazabicyclohept-2-enes
Mackay, Donald,McIntyre, Deane D.,Wigle, Ian D.
, p. 1999 - 2010 (2007/10/02)
The bicyclic diazetidines (3), (11), and (17), have trans-pyramidal nitrogens, the ester group on N(7) being sterically protected and very unreactive.Its alkyl group is close to the face of the aryl ring attached to C(1) and shows remarkable shielding eff