Chapter One This chapter reviews the historical background of the fluorination using both elemental fluorine and N-F reagents. It relates the properties and preparations of these electrophilic reagents. And finally it discusses the use of these reagents in selective electrophilic fluorination (formation of C-F bond from C-H bond) of organic compounds. Chapter Two, Three and Four These chapters present our investigations into the fluorination of hydrocarbon systems containing an electron withdrawing group (ewg).Chapter Two shows the difference in reactivity of elemental fluorine and Selectfluor(^TM) towards aldehydes and ketones. Select fluor gives rise to a-fluorinated compound when reacting with ketones (acyclic and cyclic ones) whereas different results were observed using fluorine. In Chapter Three aldehydes are submitted to fluorination which occurred at the carbonyl and not on the chain. Finally, Chapter Four review the fluorination of nitriles using both fluorinating reagents. Chapter Five In this last Chapter we explore the fluorination of cyclic ethers (hydrocarbon systems containing an electron donating group) using both elemental fluorine and Selectfluor(^TM). Unexpected derivatives were identified. Chanter Six to Nine Experimental details relating to Chapter Two-Five