Prioritizing the ze configuration can be done by following these steps:
1.Double bond longitudinal cutting: cut the double bond longitudinally from the middle to separate the left and right parts.
2.Compare the size of the left half: see which of the substituents (L1 and L2) attached to the two carbon atoms on the left side of the double bond is larger, and choose the larger one according to the order rule.
3.Compare the size of the right half: As with the left half, compare the size of the substituents (R1 and R2) on the right, and choose the larger one.
4.Double Bond Cross Cutting: Cut the double bond horizontally from the middle and divide it into two parts.
5.Determine the configuration: Observe whether the larger left substitutes (L1 or L2) and the larger right substituents (R1 or R2) are on the ipsilateral side of the double bond. On the same side is the Z configuration ("zusammen" in German, meaning "together"), and on the opposite side is the e configuration (in German "entgegen", meaning "relative").
6.Comparison of the same atoms: If the first atom is the same, the second and third atoms are compared one by one until the order of preference is distributed.
7.Order rule: When comparing the priority of atoms or groups, follow the order rule: the number of atoms first, the larger one takes precedence; The ordinal number is the same, and the number of branches is more preferred; If the number of branches is the same, the distance from the double bond is preferred.
8.Sequence comparison: Compare atoms in two sequences, compare them one by one starting from the first one, and judge the priority of the entire sequence based on the atomic priority when encountering differences.
By following these steps, it is possible to accurately determine the Ze configuration of a double-bonded compound. In practice, detailed analysis and judgment may be required based on the structure of specific compounds.