The design of experiments (DoE) in optimization of an aerobic flow Pd-catalyzed oxidation of alcohol towards an important aldehyde precursor in the synthesis of phosphatidylinositide 3-kinase inhibitor (CPL302415)

Abstract

DoE study of the aerobic flow Pd-catalyzed oxidation of an alcohol to an aldehyde in the synthesis of PI3Kδ inhibitor. The evaluation of green metrics show that the process is sustainable in comparison with two already known stoichiometric methods.

Multistep Mechanochemical Synthesis of PZ-1190, a Multitarget Antipsychotic Agent

“…The oxidation of pharmaceutical intermediates often represents a bottleneck for the synthesis of biologically active compounds, thereby forcing pharmaceutical industries to develop environmentally and economically sustainable procedure suitable for the large-scale production of APIs . In our case, there are only few available protocols reporting the oxidation of aromatic alcohols to aldehydes or ketones in a ball mill mainly by using 2-iodoxybenzoic acid (IBX) as the oxidizing agent. , To extend this protocol to aliphatic primary alcohols, we investigated the possibility of oxidizing intermediate 2a in the presence of IBX or the more reactive Dess-Martin Periodinane (DMP) under mechanochemical conditions (Table ).…”

A novel approach to amino acid synthesis: acid-assisted reactions with dimethyl carbonate for efficient O-methylated, N,O-methylated and N-formylated derivatives

“…Intriguingly, despite these varied conditions, the prevention of racemization and epimerization risks during the reactions remained consistent (Table S6 †). The comparison of the qualitative and quantitative green metrics [93][94][95] 49 and C′ (FAPM, N-formylation) 56 ] (Table 7, see ESI † for details) clearly shows the advantages of the current methods over previous methods except for the high-temperature reaction. The previous processes necessitate workup and/or chromatographic processes that consume a considerable amount of solvent, some of which are hazardous, resulting in a high process mass intensity (PMI), E-factor, solvent intensity (SI), and water intensity (WI).…”

Development and optimization of a continuous flow ester reduction with LiAlH4 in the synthesis of a key intermediate for a PI3Kδ inhibitor (CPL302415)

“…Toluene was also a favorable solvent in order to combine the reduction in a telescoped sequence with our already developed flow oxidation of 2 to aldehyde 3 , where it was also used as a solvent. 12 The first optimization tests were done in a batch autoclave using NaO t Bu as a base.…”

“…The aim of this work was to develop the catalytic or stoichiometric reduction of ester group in 5-[2-(difluoromethyl)-1H-benzimidazol-1-yl]-7-(morpholin-4-yl) pyrazolopyrimidine-2-carboxylate (1) to the corresponding primary alcohol, {5-[2-(difluoromethyl)-1H-1,3-benzodiazol-1-yl]-7-(morpholin-4-yl)pyrazolo [1,5-a]pyrimidin-2-yl}methanol (2), in a continuous flow process in order to combine it in a telescoped sequence with Pd-catalyzed flow oxidation of 2 to aldehyde 3. 12 The hydrogenation of ester group in substrate 1 itself is quite a demanding transformation, which may lead to multiple products: the substrate with the hydrogenated benzimidazole ring (1b) (Table 1), the desired alcohol with a double bond in the benzimidazole ring (2), and alcohol with a reduced double bond in the benzimidazole ring (2b). However, in the next step of CPL302415 synthesis, we can recover the double bond in the benzimidazole ring, 12 which is very important for CPL302415 stability, but the 2b alcohol is much less soluble than 2.…”

“…12 The hydrogenation of ester group in substrate 1 itself is quite a demanding transformation, which may lead to multiple products: the substrate with the hydrogenated benzimidazole ring (1b) (Table 1), the desired alcohol with a double bond in the benzimidazole ring (2), and alcohol with a reduced double bond in the benzimidazole ring (2b). However, in the next step of CPL302415 synthesis, we can recover the double bond in the benzimidazole ring, 12 which is very important for CPL302415 stability, but the 2b alcohol is much less soluble than 2. This generates synthetic problems in the next stages, for example, higher solvent expenditure, especially in large-scale production.…”