Spiro Compound - Chirality

Chirality

Some spiro compounds exhibit axial chirality. Spiroatoms can be centers of chirality even when they lack the required four different substituents normally observed in chirality. When two rings are identical the priority is determined by a slight modification of the CIP system assigning a higher priority to one ring extension and a lower priority to an extension in the other ring. When rings are dissimilar the regular rules apply.

Spiro forms of lactones and oxazines are frequently used as leuco dyes, frequently displaying chromism - reversible change between their colorless and color form.