Development of a Continuous-Flow Sonogashira Cross-Coupling Protocol using Propyne Gas under Process Intensified Conditions
摘要:
The development of a continuous-flow Sonogashira cross-coupling protocol using propyne gas for the synthesis of a key intermediate in the manufacturing of a beta-amyloid precursor protein cleaving enzyme 1 (BACE1) inhibitor, currently undergoing late stage clinical trials for a disease-modifying therapy of Alzheimer's disease, is described. Instead of the currently used batch manufacturing process for this intermediate that utilizes TMS-propyne as reagent, we herein demonstrate the safe utilization of propyne gas, as a cheaper and more atom efficient reagent, using an intensified continuous-flow protocol under homogeneous conditions. The flow process afforded the target intermediate with a desired product selectivity of similar to 91% (vs the bis adduct) after a residence time of 10 min at 160 degrees C. The continuous-flow process compares favorably with the batch process, which uses TMS-propyne and requires overnight processing, TBAF as an additive, and a significantly higher loading of Cu co catalyst.
Compounds of the formula (I), in which M is a central building block selected from the group below in which Al, A2, K1 and K2 are as defined in the description, are novel effective tryptase inhibitors.
[EN] TRYPTASE INHIBITORS<br/>[FR] INHIBITEURS DE TRYPTASE
申请人:BYK GULDEN LOMBERG CHEM FAB
公开号:WO2002066430A1
公开(公告)日:2002-08-29
Compounds of the formula (I), in which M is a central building block selected from the group below in which A1, A2, K1 and K2 are as defined in the description, are novel effective tryptase inhibitors.