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(a) Which proton in these anomers would be expected to have these highest
(b) Why do the signals for these protons appear as doublets?
(c) The relationship between the magnitude of the observed coupling constant and the dihedral angle (when measured using a Newman projection) between C−-H bonds on the adjacent carbons of a C−-C bond is given by the Karplus equation. It indicates that an axial–axial relationship results in a coupling constant of about 9 Hz (observed range is 8–14 Hz) and an equatorial–axial relationship results in a coupling constant of about 2 Hz (observed range is 1–7 Hz). Which of V and VI is the αa anomer and which is the
(d) Draw the most stable conformer for each of V and VI.
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