Page 138 - Advanced Organic Chemistry Part A - Structure and Mechanisms, 5th ed (2007) - Carey _ Sundberg
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Table 1.P23b. Calculated 17 O Chemical Shifts in ppm 117
Planar Twisted
PROBLEMS
Formamide 390 602 212
3-Aminoacrolein 568 630 62
Squaramide O(1) 446 526 80
to rotation of the three molecules are 14.9, 8.8, and 9.9 kcal/mol, respectively.
On the basis of these data, discuss the extent of resonance interaction in each
compound.
O(1) O(2)
O O
O(1)
O CH C(3)
HO NH 2
C(2) NH 2 O(4) N(3)
3-aminoacrolein squaramide
