Racemic beta-aminosulfone compounds

A process for preparing racemic beta-aminosulfone of formula (I),

• the process comprising:
• a) reacting 3-ethoxy-4-methoxybenzaldehyde of formula (9) with a compound of formula R1—NH2 and a compound of formula R2—S(O)OH or a salt thereof to obtain an aminosulfone of formula (2):
• wherein:
• R1 is an amino protecting group;
• and
• R2 is a C1-C6 alkyl, a substituted C1-C6 alkyl, a C6-C10 aryl or a substituted C6-C10 aryl;
• b) converting the aminosulfone of formula (2) into a sulfone of formula (3) by treatment with a carbanion derived from dimethyl sulfone:
• and
• c) deprotecting the sulfone of formula (3) to obtain 1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethan-1-amine of formula (1) in the form of a racemic mixture.