Description and references
Of the two isomers, the endo-form
is more stable than the exo-form: Cookson, J. Chem. Soc. 1954, 282. Prepn
of endo-form: Kipping, Pope, ibid. 63, 548 (1893). Prepn of exo-form by isomerization
of endo-form: Lowry, Steele, ibid. 107, 1382 (1915). uv spectra: Lowry, Owen, J. Chem. Soc. 129, 606 (1926).
Crystal structure of endo-form: Wiebenga, Krom, Rec. Trav. Chim. 65, 663 (1946).
Configuration: Cookson, loc. cit.; Kumler et al., J. Am. Chem. Soc. 83, 2711 (1961). Review: The Terpenes vol. II, J. L. Simonsen, Ed. (University Press, Cambridge,
2nd ed., 1949) p 397.
Derivative
endo-Form.
Nomenclature
α-Chloro-d-camphor; 3α-chloro-d-camphor; camphor monochlorated. Properties
Monoclinic prisms from alc, mp 94°. Volatile with steam. [α]D +96.2° (c = 5 in alc). Practically insol in water. Sol in alcohol, chloroform, ether.
uv max (cyclohexane): 305 nm (log ε 1.72).Derivative
exo-Form.
Nomenclature
α′-Chloro-d-camphor; 3β-chloro-d-camphor. Properties
Crystals from alc, mp 117°. [α]D +35° (c = 5 in alc). Readily sol in all
ordinary solvents, except water and formamide. Much more sol in 96%
alc than endo-form. On standing, loses HCl. uv max (cyclohexane): 306 nm (log ε 1.75).