Suzuki–Miyaura Cross-Couplings under Acidic Conditions

Synthesis ◽  
2019 ◽  
Vol 52 (06) ◽  
pp. 882-892
Author(s):  
Lucas Pruschinski ◽  
Ana-Luiza Lücke ◽  
Tyll Freese ◽  
Sean-Ray Kahnert ◽  
Sebastian Mummel ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Reaction Time ◽  
Sodium Carbonate ◽  
Acid Water ◽  
Reaction Parameters ◽  
Acid Base ◽  
Acetic Acid Water ◽  
Acidic Conditions ◽  
Carbonate Reaction

Suzuki–Miyaura reactions with Pd(PPh3)4 have been carried out using lithium N-phenylsydnone-4-carboxylate as additive, which gave best yields at pH 5.7 in a mixture of acetic acid, water, and sodium carbonate. Reaction parameters such as the Pd source, the solvent, reaction time and temperature, acid, base and carboxylate have been varied and some representative examples of the Suzuki–Miyaura reaction have been examined.

Lignin Separation and Antioxidant Capacity from Acanthopanax senticosus Remainders Using Acetic Acid-Water System

2011 ◽  
Vol 311-313 ◽  
pp. 1514-1517
Author(s):  
Ming Hua Zhu ◽  
Gui Zhen Fang ◽  
Shi Yan Han ◽  
Hai Hong Rong ◽  
Jun Guo ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Reaction Time ◽  
Antioxidant Capacity ◽  
Reaction Temperature ◽  
Water System ◽  
Solution Concentration ◽  
Acid Water ◽  
Acanthopanax Senticosus ◽  
Acetic Acid Water ◽  
Acetic Acid Lignin

Lignin was extracted from Acanthopanax senticosus remainders after pharmaceutical production process, with acetic acid-water as extracting reagent. Four factors effects, namely reaction temperature from 160°C to 220°C, reaction time from 40 min to 100 min, acetic acid concentration from 50% to 80% and solid-liquid ratio from 1:40 to 1:5, were studied and optimized by a four-level orthogonal array design (OAD) on lignin antioxidant capacity. The results indicated the reaction temperature and reaction time were significant factors among these factors. At the same lignin solution concentration, the acetic acid lignin antioxidant capacity was better than that of Kraft lignin, but much lower than that of butylated hydroxyanisole (BHA).

Liquid Structure of Acetic Acid−Water and Trifluoroacetic Acid−Water Mixtures Studied by Large-Angle X-ray Scattering and NMR

2007 ◽  
Vol 111 (31) ◽  
pp. 9270-9280 ◽  
Author(s):  
Toshiyuki Takamuku ◽  
Yasuhiro Kyoshoin ◽  
Hiroshi Noguchi ◽  
Shoji Kusano ◽  
Toshio Yamaguchi
Keyword(s):  
Acetic Acid ◽  
Trifluoroacetic Acid ◽  
Large Angle ◽  
Liquid Structure ◽  
Acid Water ◽  
X Ray ◽  
X Ray Scattering ◽  
Acetic Acid Water ◽  
Ray Scattering

Acetic acid/water separation by pervaporation with silica filled PDMS membrane

2011 ◽  
Vol 51 (5) ◽  
pp. 819-825 ◽  
Author(s):  
Housheng Hong ◽  
Longxiang Chen ◽  
Qingwen Zhang ◽  
Zheran Zhang
Keyword(s):  
Acetic Acid ◽  
Acid Water ◽  
Pdms Membrane ◽  
Water Separation ◽  
Acetic Acid Water

Diagonal Chromatography for the Selective Purification of Tyrosyl Peptides

1974 ◽  
Vol 52 (11) ◽  
pp. 1013-1017 ◽  
Author(s):  
William H. Cruickshank ◽  
Barry L. Malchy ◽  
Harvey Kaplan
Keyword(s):  
Acetic Acid ◽  
Stationary Phase ◽  
Enzymatic Digestion ◽  
Acid Water ◽  
Chromatographic Purification ◽  
Amino Groups ◽  
Chromatographic System ◽  
Original Direction ◽  
Acetic Acid Water ◽  
Citraconic Anhydride

Thiolysis of an O-dinitrophenyl-tyrosyl peptide results in an increased solubility in the stationary phase of a n-butanol – acetic acid – water – pyridine (15:3:12:10) (BAWP) paper chromatographic system. It is shown that this property can be used to form the basis of a diagonal paper chromatographic purification of tyrosyl peptides from enzymatic digests of proteins. The amino groups of the protein are first reacted with citraconic anhydride and then the citraconyl protein is reacted with 1-fluoro-2,4-dinitrobenzene. The dinitrophenyl-citraconyl protein is subjected to enzymatic digestion, applied to a strip of Whatman 3 MM paper, thiolyzed with 5% 2-mercaptoethanol in acetone, and subjected to chromatography using BAWP as solvent. A guide strip is removed, thiolyzed with 5% 2-mercaptoethanol in 25% pyridine, and resubjected to chromatography in BAWP at right angles to the original direction of chromatography. The tyrosyl peptides are displaced off the diagonal towards the origin. The off-diagonal peptides are isolated from the original chromatogram by thiolysis and chromatography using the diagonal chromatogram to locate the positions of the dinitrophenyl-tyrosyl peptides.

scholarly journals Study of Regularities and Optimization of the Process of Fir Wood Peroxide Delignification in the Medium of “Acetic Acid – Water” in the Presence of Sulfuric Acid Catalyst

2019 ◽  
pp. 590-603
Author(s):  
Olga V. Yatsenkova ◽  
Andrei M. Skripnikov ◽  
Boris N. Kuznetsov
Keyword(s):  
Acetic Acid ◽  
Lignin Content ◽  
Reaction Medium ◽  
Acid Catalyst ◽  
Acid Water ◽  
High Yield ◽  
Process Conditions ◽  
Residual Lignin ◽  
Acetic Acid Water ◽  
Peroxide Delignification

The work describes a one-stage method of cellulose obtaining from fir wood based on peroxide delignification of wood under mild conditions (100 °C, atmospheric pressure) in the presence of acetic acid, water and catalyst of 2% wt. H2SO4. The possibility of obtaining cellulose with a residual lignin content <1% wt. at a low concentration of hydrogen peroxide (3% wt.) in the reaction medium was established. The optimal concentrations of reagents (Н2О2 – 3% wt., CH3COOH – 38.9% wt.) and the duration of the process (4 h) were determined by experimental and calculation methods. This conditions provide a high yield of cellulose product (≥45% wt.) with a low content of residual lignin (<1% wt.). The composition and structure of fir cellulose was studied by chemical analysis and by FTIR and SEM methods. The cellulosic product which was obtained in optimal process conditions is high-quality cellulose

Ternary liquid equilibria system: Acetic acid + water + toluene

2007 ◽  
Vol 23 (5) ◽  
pp. 323-328 ◽  
Author(s):  
P. Dakshinamurty ◽  
V. Subrahmanyam ◽  
M. Narsimha Rao
Keyword(s):  
Acetic Acid ◽  
Acid Water ◽  
Acetic Acid Water
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