Spiroheptane refers to spirocyclichydrocarbons with the formula C(CH2)6. The parent symmetrical member of this group of compounds is spiro[3.3]heptane, which features a pair of cyclobutane rings sharing one carbon. The parent unsymmetrical member is spiro[2.4]heptane, which features cyclopropyl and cyclopentyl rings sharing one carbon.
An early example of a spiro[3.3]heptane is the dicarboxylic acidC[(CH2)2CH(CO2H)]2, also called Fecht's acid in honor of H. Fecht, of the Strasbourg Institute of Chemistry, the person who obtained this compound. His route involved alkylation of malonic esters with the tetrabromide of pentaerythritol, a method modeled after the work on spiropentane.[1][2][3]
^Hulshof, L. A.; Vos, Aafje; Wynberg, Hans (1972). "Crystal and molecular structure and absolute configuration of d-sprio[3.3]heptane-2,6-dicarboxylic acid at -160.deg". The Journal of Organic Chemistry. 37 (11): 1767–1770. doi:10.1021/jo00976a022.