Patent ID: 8592588

Claim:
A process for adding a side chain to a starting material comprising reacting together in a one-pot reaction: (i) a compound of formula I: or a partially or completely purified stereoisomer thereof, or a salt thereof, wherein R 3 is an alkyl group; (ii) an amine of formula R 1 R 2 NH wherein R 1 and R 2 are the same or different and independently represent organic groups having, in total, less than 20 non-hydrogen atoms and include alkyls, substituted alkyls, alkenyls, substituted alkenyls, alkynyls, substituted alkynyls, alkoxys, substituted alkoxys, acyls, substituted acyls, aryls, substituted aryls, heteroalkyls, substituted heteroalkyls, heteroaryls, substituted heteroaryls, heterocycles and substituted heterocycles; and (iii) phosgene or a reactive equivalent thereof, to provide a solution comprising a compound of formula III: