This thesis describes the development of a more economical catalytic system for the N-alkylation of amines by “borrowing hydrogen” and its application in the synthesis of a variety of amines including the dopamine agonist Piribedil and the antihistamine agents Antergan and Tripelennamine. Chapter 2 describes the development of the ruthenium-catalysed N-alkylation of primary amines with primary alcohols by “borrowing hydrogen”. Chapter 3 describes the application of the ruthenium-catalysed N-alkylation of secondary amines with primary alcohols by “borrowing hydrogen”. The ruthenium-catalysed synthesis of dimethylamines by “borrowing hydrogen” is also described and a mechanistic proposal for the N-alkylation of alcohols with amines has been proposed. Chapter 4 describes the role of amines in pharmaceuticals and the ruthenium-catalysed synthesis of Piribedil, Antergan and Tripelennamine by “borrowing hydrogen”.