Abstract: Three syntheses of spiro [3.3] hepta-1, 5-diene (1) are described:(a) pyrolysis of spiro [3.3] heptane-2, 6-bis (trimethy1ammonium) hydroxide in a Hofmann elimination,(b) heating the amine oxide 14 of spiro [3.3] heptane-2, 6-bis (dimethylamine)(8), and (c) a Norrish type I1 photochemical reaction of spiro [3.3] heptane-2, 6-bis (aceto-phenone)(15). Optically active Fecht acid (6) has been used for the preparation of racemic spirocycle 1 ...
![(+)-2,6-dibromo-spiro[3.3]heptane-dicarboxylic acid-(2.6) Structure](https://image.chemsrc.com/caspic/486/52097-91-3.png)
![2,6-Dibromospiro[3.3]heptane-2,6-dicarboxylic ac Structure](https://image.chemsrc.com/caspic/416/55249-70-2.png)
