Cesium carbonate as a mediated inorganic base in some organic transformations

Rabie, Ramy; Hammouda, M.; Elattar, Khaled M.

doi:10.1007/s11164-016-2744-z

Cited by 27 publications

(17 citation statements)

References 78 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When working in MeCN the best results have been obtained with caesium carbonate as base to deprotonate the amide-NH without the need of a crown ether (Scheme 1). The advantage of caesium carbonate in organic syntheses 45 as well as for the Nalkylation of aromatic cyclic imides 46 has been shown previously. In most of the cases, as well as in this particular reaction on DPP, the common solvents from the dipolar aprotic family are the DMF and the DMSO.…”

Section: Resultsmentioning

confidence: 74%

Towards more sustainable synthesis of diketopyrrolopyrroles

et al. 2019

View full text Add to dashboard Cite

show abstract

Section: Resultsmentioning

confidence: 74%

Towards more sustainable synthesis of diketopyrrolopyrroles

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Using our literature benchmark reaction ( 5 ) in 1,2-dimethoxyethane (DME) solvent and targeted primary alkyl-halide examples ( 6 and 7 ), we conducted an initial screening of bases (entries B1–B10). As shown with entry B1, sodium carbonate gave similar conversions across the three products 5 , 6 , and 7 (58–68%), with a slightly lower yield than reported by MacMillan et al Of note, cesium carbonate, which is often utilized as a more organic soluble carbonate source, − was surprisingly found to be detrimental for pyran 5 (30%, entry B6) and was not explored further. For the initial homogeneous starting conditions, three representative organic base classes were selected (guanidines, pyridines, and alkylamines).…”

Section: Resultsmentioning

confidence: 59%

Photoredox Iridium–Nickel Dual Catalyzed Cross-Electrophile Coupling: From a Batch to a Continuous Stirred-Tank Reactor via an Automated Segmented Flow Reactor

Duvadie¹,

Pomberger

et al. 2021

Org. Process Res. Dev.

View full text Add to dashboard Cite

Organic reaction optimization for batch to flow transfer represents a main challenge for process chemists in drug synthesis. Several factors such as reactant concentration, residence/reaction time, or homo-/heterogeneity need to be taken into consideration during the fine-tuning of reaction conditions toward typical scale-up goals, such as high space–time yield. Herein, we present reaction optimization for photoredox iridium–nickel dual catalyzed cross-electrophile coupling with a focus on developing homogeneous starting conditions. During the screening, special attention was put on the replacement of inorganic bases with homogeneous organic bases, and the effect of pK a on the reaction yield was investigated. Screening was conducted via an automated segmented flow reactor at 15 μL scale, and subsequentially, the conditions were transferred to a 5 mL photo-continuous stirred-tank reactor (CSTR) cascade to demonstrate multigram continuous flow synthesis during a 24 h steady operation.

show abstract

“…The different bases produced different yields as represented in Table . From the results, it is observed that Cs 2 CO 3 provide better yield than other bases used in the study which can be attributed to the ability of the base to easily donate its carbonate ion for replacement of the halide ion in the oxidative addition step of the catalytic cycle . The C‐1 catalyzed reaction yields 89.9%, whereas C‐2 yields 76.1% of the product.…”

Section: Resultsmentioning

confidence: 90%

Retracted: Catalytic activity of Fe(II) and Cu(II) PNP pincer complexes for Suzuki coupling reaction

Kumar

Ansari

Bhat

2017

Applied Organom Chemis

View full text Add to dashboard Cite

Iron and copper PNP pincer complexes of the type [Fe(L)SO4] and [Cu(L)OCOCH3] are reported and represented as C‐1 and C‐2 catalyst. Both the complexes were synthesized using bis(diphenylphosphino)pyridine‐2,6‐diamine [L], and salts of ‘Fe’ and ‘Cu’ by direct coordination method. The as synthesized complexes were characterized using FTIR, UV–Vis, mass analysis and TGA. The effect of reaction time, catalyst load, solvent and base on the reaction between phenylboronic acid and para substituted bromobenzenes in the presence of the catalysts were investigated for evaluating the catalytic efficiency of the complexes. The results obtained highlight the enhanced C‐C coupling reactions with the use of 0.4 mol% of the catalyst C‐1 in 14 h and 0.6 mol% of C‐2 in 16 h respectively with Cs2CO3 base and ACN as solvent media. Of the two complexes reported, C‐1 with iron as catalytically active metal is more stable and active towards coupling which is reflected in its better coupling yields in lesser reaction time compared to copper bearing C‐2 complex.

show abstract

Cesium carbonate as a mediated inorganic base in some organic transformations

Cited by 27 publications

References 78 publications

Towards more sustainable synthesis of diketopyrrolopyrroles

Towards more sustainable synthesis of diketopyrrolopyrroles

Photoredox Iridium–Nickel Dual Catalyzed Cross-Electrophile Coupling: From a Batch to a Continuous Stirred-Tank Reactor via an Automated Segmented Flow Reactor

Retracted: Catalytic activity of Fe(II) and Cu(II) PNP pincer complexes for Suzuki coupling reaction

Contact Info

Product

Resources

About