US 12,221,438 B2
Continuous process for the preparation of trazodone
Tommaso Iacoangeli, Rome (IT); Leonardo Mario Moro, Aprilia (IT); Giuliano Caracciolo Torchiarolo, Aprilia (IT); Claudia Cavarischia, Rome (IT); and Guido Furlotti, Rome (IT)
Assigned to AZIENDE CHIMICHE RIUNITE ANGELINI FRANCESCO A.C.R.A.F. S.p.A., Rome (IT)
Appl. No. 16/967,337
Filed by AZIENDE CHIMICHE RIUNITE ANGELINI FRANCESCO A.C.R.A.F. S.p.A., Rome (IT)
PCT Filed Feb. 5, 2019, PCT No. PCT/EP2019/052690
§ 371(c)(1), (2) Date Aug. 4, 2020,
PCT Pub. No. WO2019/154770, PCT Pub. Date Aug. 15, 2019.
Claims priority of application No. 18155470 (EP), filed on Feb. 7, 2018.
Prior Publication US 2021/0032243 A1, Feb. 4, 2021
Int. Cl. C07D 471/04 (2006.01); B01J 14/00 (2006.01); B01J 19/00 (2006.01); B01J 19/18 (2006.01)
CPC C07D 471/04 (2013.01) [B01J 14/00 (2013.01); B01J 19/0093 (2013.01); B01J 19/18 (2013.01); B01J 2219/00029 (2013.01); B01J 2219/00033 (2013.01)] 21 Claims
 
1. A continuous process for the preparation of trazodone base (IV), comprising reacting N-(3-chlorophenyl)-N′-(3-chloropropyl)-piperazine (II) and s-triazolo-[4,3-a]-pyridin-3-one (III), according to reaction scheme 2:

OG Complex Work Unit Chemistry
comprising continuously mixing in a flow reactor an alkaline aqueous solution of s-triazolo-[4,3-a]-pyridin-3-one (III) and an organic solution of N-(3-chlorophenyl)-N′-(3-chloropropyl)-piperazine (II), and continuously recovering trazodone base (IV).