Salts of aza-bicyclic di-aryl ethers and methods to make them or their precursors

A process for the production of a compound of formula I

• or a salt thereof, the process comprising:
• reacting a compound of formula II
• or a salt thereof, with a compound of formula V
• or a salt thereof, at elevated temperature in the presence of a base and an inert dipolar aprotic solvent,
• wherein the base is (M2)OC(R)3, wherein M2 is sodium or potassium and each R independently is C1-6alkyl or two R together with the carbon atom they are bound to form C4-6 cycloalkyl, or the base is a hydroxide base,
• to form the compound of formula I;
• and
• optionally converting the compound of formula Ito a salt thereof.