Spiro Compounds

Spiro Compounds

A spiro compound is a bicyclic organic compound with rings connected through just one atom. The rings can be different in nature or identical. The connecting atom is also called the spiroatom, most often a quaternary carbon (“spiro carbon”).

All spiro compounds have the infix spiro followed by square brackets containing the number of atoms in the smaller ring and the number of atoms in the larger ring excluding the spiroatom itself; the numbers being separated by a dot.

For example compound A is called 1-bromo-3-chlorospiro decan-7-ol and compound B is called 1-bromo-3-chlorospiro decan-7-ol. The spiro compound consisting of a cyclohexane ring and a cyclopentane ring is called spiro[4.5]decane. This nomenclature was proposed by Adolf von Baeyer in 1900.

in spiro compounds two rings are fused at one C-atom (spiral C-atom).

spiro compounds

It is named as prefix spiro [x, y] alk + f.gp’s name or suffix names

Here x,y are in increasing number and these are number of C-atom present in two rings.