ABSTRACT - 602791 The disclosure relates to a process of preparing a compound of Formula (I) or salt thereof: comprising reacting a compound of Formula (II) with a compound of Formula (III) to form a compound of Formula (I), or salt thereof wherein the process further comprises preparing the compound of Formula (II) by a process comprising reacting a compound of Formula (IIa) with a compound of Formula (IIb) for a length of time sufficient to generate a compound of Formula (II), wherein X1 is chloro, bromo, or iodo and wherein the reacting of the compound of Formula (IIa) with the compound of Formula (IIb) is carried out in the presence of proline.