Parkinson's disease is the second most prevalent aging-related neurodegenerative disorder. Cell death in the substantia nigra, a motor region of the nervous system, is the key factor for the emergence of motor deficits in patients, although its critical role in Parkinson's disease pathogenesis is put into question. This book explores how halogenation stress could participate in neuronal damage of the nervous system and parkinsonian deficits. Following this, new insights into the C-F bonding nature of graphite fluorides with different fluorine concentrations C4F, C2F and C1F are presented. They are based on recent data from bulk techniques, which are very sensitive to the atomic local and electronic structure and C hybridisation such as X-ray Raman Scattering and Pair Distribution Function analysis. Lastly, a novel bromine-containing Still -- Gennari-type phosphonate reagent, methyl 2-(bis(2,2,2-trifluoroethoxy)phosphoryl)-2-bromoacetate is designed, synthesised, and applied to the stereoselective construction of trisubstituted alkenes via bromomethylenation of carbonyl groups.