Regioselective halogenation of nicotine and substituted nicotines

A method for of making a compound of Formula Ia:

• wherein:
• R2 is H, alkyl, aryl, alkoxy or halo;
• R4 and R5 are H, alkyl or aryl, or R4 is —SiR20R21R22, wherein R20, R21 and R22 are each independently alkyl or aryl;
• R7 is H, alkyl or aryl;
• and
• X is halo;
• comprising the steps of:
• (a) metalating a compound of Formula II:
• wherein R6 is H, with a metal base complex to form an organometallic intermediate compound;
• and then
• (b) reacting said organometallic intermediate compound with a halogenating agent to produce a compound of Formula Ia.