Follow SiliCycle on Facebook Follow SiliCycle on Twitter Follow SiliCycle on LinkedIn Watch our videos on Youtube

Diastereoselective synthesis of cis-N-Boc-4-aminocyclohexanol with reductive ring opening method using continuous flow

> back to SiliaMetS Case Studies

N-protected cis-4-aminocyclohexanol derivatives are valuable intermediates in the syntheses of APIs.

Compared with previously reported batch processes, the present multistep flow process is much more efficient in synthetizing valuable 4-aminocyclohexanol derivatives, and avoids some isolation and purification steps. In this procedure, a nitroso hetero-Diels-Alder cycloaddition step using MnO2 as the oxidant was fully integrated to a novel continuous flow process for the hydrogenation and ring opening of cycloadducts to the corresponding cis-4-aminocyclohexanols using H-Cube Pro (see scheme).

It was shown that Raney Nickel was a significantly more performant catalyst compared to 10% Pd/C and 5% Ru/C in this last cleavage, and highly selective (≥ 99 % toward final cis-4-aminocyclohexanol). Yet, the Raney Nickel cartridge lost its activity after a few measurements. A possible manganese leaching into the reaction mixture was presumed as the cause for catalyst deactivation. Based on the atom absorption measurements the average extent of manganese was 15 ppm in the reaction mixture. Filling the end of the MnO2 column with SiliaMetS AMPA as a Mn scavenger allowed the Raney nickel catalyst activity to be kept constant for longer time.

Szabó, B. et al. J. Flow Chem., 2019, XX, XXX-XXX; DOI: /10.1007/s41981-018-00028-3

 

Read more

2 Item(s)

Set Descending Direction
per page

List  Grid 

  1. SiliaMetS AMPA (R85130B)

    SiliaMetS AMPA (R85130B)

    SiliaMetS AMPA is an aminomethylphosphonic acid ligand known for its excellent metal-bonding properties. It's the first AMPA silica-supported on the market and a very powerful tool to scavenge Lanthanides. Best scavenger for: Al, Ce, Gd, La, Ni, Sb & V. Good scavenger for: Co, Cu, Fe, M & Zn.
  2. Metal Scavenging with SiliaMetS AMPA

    Metal Scavenging with SiliaMetS AMPA

    Application Note (7 pages) - SiliCycle's SiliaMetS AMPA effectively eliminates Iron, Copper, Zinc, Manganese, Lanthanides, Antimony and Nickel.

2 Item(s)

Set Descending Direction
per page

List  Grid