
TY  - JOUR
A1  - Brecknell, Douglas J. 
A1  - Carman, Raymond M. 
A1  - Edwards, Ross A. 
A1  - Hansford, Karl A. 
A1  - Karoli, Tomislav 
A1  - Robinson, Ward T. 
T1  - Halogenated Terpenoids. XXIX The 1-Bromo 1-Bromomethyl Cyclohexyl System
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1997
VL  - 50
IS  - 7
SP  - 689
EP  - 700
KW  - 
UR  - https://doi.org/10.1071/C96188 
N2  - Bromination of methylene groups exocyclic to cyclohexyl systems normally affords two isomeric products; the axial 1-bromo equatorial 1-bromomethyl compound and the axial 1-bromomethyl equatorial 1-bromo derivative. Free energy differences between these two isomers, and the conformations adopted by the axial 1-bromomethyl group, have been explored by n.m.r. spectroscopy, by X-ray crystallography and by MM3 calculations. Evidence is presented to show that the ax-bromomethyl group exists primarily as those rotamers which site the bromine atom synclinal to the vicinal bromine. The A value for a bromomethyl group in this system is then similar to that of an unsubstituted methyl group. 
ER  -

