Compounds that contain a carbon-nitrogen double bond are capable of stereoisomerism much l...

Compounds that contain a carbon-nitrogen double bond are capable of stereoisomerism much like that seen in alkenes. The structures

are stereoisomeric Specifying stereochemistry in these systems is best done by using E-Z descriptors and considering the nitrogen lone pair to be the lowest priority group. Write the structures, clearly showing stereochemistry, of the following:

(a)    (Z)-CH3CH=NCH3

(b)    (E)-Acetaldehyde oxime

(c)    (Z)-2-Butanone hydrazone

(d)    (E)-Acetophenone semicarbazone