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Luís S Monteiro et al.
Amino acids, 43(4), 1643-1652 (2012-02-22)
Recently we reported the use of a sequence of alkylation and dehydration methodologies to obtain N-ethyl-α, β-dehydroamino acid derivatives. The application of this N-alkylation procedure to several methyl esters of β,β-dibromo and β-bromo, β-substituted dehydroamino acids protected with standard amine
Brian C Anderson et al.
Biomaterials, 23(22), 4345-4352 (2002-09-11)
Several homopolymers and copolymers of 2-(diethylamino)ethyl methacrylate (DEAEM) and poly(ethylene glycol) methyl ether methacrylate (PEGMEM) were synthesized using anionic polymerization initiated by potassium t-butoxide. The polymers were characterized by average molecular weight, polydispersity and monomeric unit composition. A very narrow
Yong Guo et al.
Organic & biomolecular chemistry, 7(8), 1716-1722 (2009-04-04)
Alpha-fluoro-alpha-aryl-ketones were synthesized by the Pd-catalyzed cross-coupling of aryl bromides with either alpha-fluoroketones or their corresponding silyl enol ethers. The direct arylation with an alpha-fluoroketone requires a strong base, such as potassium tert-butoxide, and under these conditions the presence of
Astrid Beyer et al.
Organic letters, 14(15), 3948-3951 (2012-07-17)
Potassium tert-butoxide-mediated intramolecular α-arylations of fluoro- and chloro-substituted anilides provide oxindoles in DMF at 80 °C. In this manner, diversely substituted products have been obtained in moderate to high yields.
Anton A Toutov et al.
Nature, 518(7537), 80-84 (2015-02-06)
Heteroaromatic compounds containing carbon-silicon (C-Si) bonds are of great interest in the fields of organic electronics and photonics, drug discovery, nuclear medicine and complex molecule synthesis, because these compounds have very useful physicochemical properties. Many of the methods now used
Eiji Tayama et al.
Organic & biomolecular chemistry, 6(20), 3673-3680 (2008-10-10)
The Stevens rearrangement of N-allylic alpha-aryl amino acid-derived ammonium salts and the Sommelet-Hauser rearrangement of N-benzylic alpha-alkyl amino acid-derived ammonium salts are shown to proceed with remarkably high levels of diastereoselectivity. The methods presented in this work provide new routes
H S Kim et al.
Chemistry and physics of lipids, 62(1), 55-67 (1992-07-11)
The enolate of 3 beta-hydroxy-5 alpha-cholest-8(14)-en-15-one (II), formed upon treatment of II with potassium tert-butoxide in tert-butanol, was alkylated with ethyl iodide. In addition to the major products, 3 beta-hydroxy-14 alpha-ethyl-5 alpha-cholest-7-en-15-one and its 3 beta-ethyl ether, small amounts of
Markus Jonek et al.
Chemistry (Weinheim an der Bergstrasse, Germany), 21(44), 15759-15768 (2015-09-24)
4-Phenylsemicarbazide and 1,5-diphenylcarbazide are suitable starting materials for the syntheses of N-heterocyclic carbene (NHC) compounds with new backbone structures. In the first case, cyclisation and subsequent methylation leads to a cationic precursor whose deprotonation affords the triazolon-ylidene 2, which was
Chang-Liang Sun et al.
Nature chemistry, 2(12), 1044-1049 (2010-11-26)
The direct functionalization of C-H bonds has drawn the attention of chemists for almost a century. C-H activation has mainly been achieved through four metal-mediated pathways: oxidative addition, electrophilic substitution, σ-bond metathesis and metal-associated carbene/nitrene/oxo insertion. However, the identification of
Wen-Sen He et al.
Bioresource technology, 114, 1-5 (2012-04-03)
The effects of solvents with different log P values, and of lipases on the synthesis of water-soluble plant stanol derivatives were investigated. Results showed that conversion in solvents with log P<0.37 was mainly controlled by the hydrophobicity of the solvent
Cross coupling: When is free really free?
Nicholas E Leadbeater
Nature chemistry, 2(12), 1007-1009 (2010-11-26)
Huaiqing Zhao et al.
Chemical communications (Cambridge, England), 49(23), 2323-2325 (2013-02-14)
A macrocyclic aromatic pyridone pentamer was shown to catalyze highly efficient transition-metal-free arylations of unactivated aromatic C-H bonds with aryl iodides and bromides in the presence of potassium tert-butoxide.
Chang-Liang Sun et al.
Chemical communications (Cambridge, England), 47(35), 9813-9815 (2011-08-10)
Polycycles can be produced with different linkages (A, B = O, N, C, S) by constructing biaryl C-C bonds via neocuproine-KO(t)Bu promoted cross coupling between C-Xs and C-Hs.
Wei Liu et al.
Chemical communications (Cambridge, England), 49(29), 2983-2985 (2013-03-07)
Simple and cheap alcohols can promote the direct arylation of unactivated arenes with aryl iodides and bromides in the presence of potassium tert-butoxide. This transition-metal-free aromatic C-H transformation offers a cheap and easy practical way to synthesize biaryls under mild
Jean-Marc Gaudin et al.
Chemical communications (Cambridge, England), (5)(5), 588-590 (2008-01-23)
The simpler the better (or going green): The first examples of the catalytic addition of 1,3-dienes to simple ketones or nitriles are described. These reactions can be effected on a kilogram scale, representing the shortest access featuring a perfect atom
David K Robbins et al.
Journal of pharmaceutical and biomedical analysis, 31(1), 63-74 (2003-02-01)
Fluoxetine hydrochloride has been prepared using two similar synthetic routes, both of which rely upon an ether formation reaction mediated by a base. The base used can affect the impurity profile of this reaction. It was proposed that the synthesis
Bapurao Surnar et al.
Nanoscale, 7(42), 17964-17979 (2015-10-16)
Platinum drug delivery against the detoxification of cytoplasmic thiols is urgently required for achieving efficacy in breast cancer treatment that is over expressed by glutathione (GSH, thiol-oligopeptide). GSH-resistant polymer-cisplatin core-shell nanoparticles were custom designed based on biodegradable carboxylic functional polycaprolactone
E Crespo-Corral et al.
Journal of chromatography. A, 1209(1-2), 22-28 (2008-10-01)
The usefulness of the potassium tert-butoxide/dimethyl sulphoxide/ethyl iodide reaction with carbamate and phenylurea herbicides, and its application to phenoxy acids as a way to prevent hazards and toxicity of the sodium hydride/dimethyl sulphoxide/methyl iodide reaction was studied. Using factorial design
Chia-Ying Lee et al.
The Journal of organic chemistry, 69(6), 2106-2110 (2004-04-03)
Various 2-(6-substituted 3(Z)-hexen-1,5-diynyl)anilines 1a-g were treated with potassium tert-butoxide or potassium 3-ethylpentanoxide in NMP at 60 degrees C for 2 h to give the corresponding 5-substituted carbazoles 2a-g in 36-65% yields together with indoles 9a-g in 21-40% yields, respectively. Exposing
Ian R Baxendale et al.
Journal of combinatorial chemistry, 7(3), 483-489 (2005-05-10)
A series of substituted aliphatic nitriles have been trimerized to their corresponding pyrimidine structures under solvent-free conditions in the presence of catalytic quantities of potassium tert-butoxide using a focused microwave reactor. Multigram quantities of the corresponding 4-aminopyrimidines have been prepared
Hajime Ito et al.
Chemical communications (Cambridge, England), 48(64), 8006-8008 (2012-07-10)
The regio- and diastereoselective silaboration of aromatic alkenes with a silylboron compound proceeds in the presence of a catalytic amount of potassium tert-butoxide, providing a complementary method to the corresponding transition metal-catalyzed reactions.
Aurélie Mallinger et al.
The Journal of organic chemistry, 74(3), 1124-1129 (2008-12-24)
3-Aryltetronic acids were prepared in one step by treatment of a mixture of methyl arylacetates and methyl hydroxyacetates with potassium tert-butoxide, via tandem transesterification/Dieckmann condensation. Several mushroom or lichen pigments, vulpinic acids, were synthesized from 3-(4-methoxyphenyl)tetronic acid in three steps
Scott E Denmark et al.
Chemistry (Weinheim an der Bergstrasse, Germany), 12(19), 4954-4963 (2006-05-04)
This paper chronicles the conceptual development, proof of principle experiments, and recent advances in the palladium-catalyzed cross-coupling reactions of the conjugate bases of organosilanols. The discovery that led to the design and refinement of this process represents a classical illustration
Biao Gu et al.
The Analyst, 140(8), 2778-2784 (2015-02-27)
A novel ratiometric fluorescent Hg(2+) detecting system was rationally developed based on the typical excited state intramolecular proton transfer (ESIPT) characteristic of the latent fluorophore, 2-(1-(p-tolyl)-1H-phenanthro[9,10-d]imidazol-2-yl)phenol (Pol) and the Hg(2+)-mediated cleavage of the vinyl group. The probe responds selectively to
Subhadip De et al.
Organic letters, 14(17), 4466-4469 (2012-08-16)
A transition-metal-free intramolecular dehydrohalide coupling via intramolecular homolytic aromatic substitution (HAS) with aryl radicals has been developed in the presence of potassium tert-butoxide and an organic molecule as the catalyst. The methodology has been applied to a concise synthesis of
H Takigami et al.
Water science and technology : a journal of the International Association on Water Pollution Research, 53(11), 43-50 (2006-07-26)
Capacitor oil samples (PCBs > 90%wt) were treated in a bench scale experiment to investigate the destruction of PCBs during chemical destruction processes (a catalytic hydrodechlorination treatment with palladium carbon and additional treatment with potassium tert-butyloxide). Using those results, this
Petr Toman et al.
Acta biomaterialia, 23, 250-262 (2015-05-20)
Poly(lactic acid), which has an inherent tendency to form colloidal systems of low polydispersity, and alkylglyceryl-modified dextran - a material designed to combine the non-immunogenic and stabilising properties of dextran with the demonstrated permeation enhancing ability of alkylglycerols - have
One-step methodology for the synthesis of FA picolinyl esters from intact lipids.
Destaillats F and Angers P
Journal of the American Oil Chemists' Society, 79(3), 253-256 (2002)
Mizoroki-heck-type reaction mediated by potassium tert-butoxide.
Eiji Shirakawa et al.
Angewandte Chemie (International ed. in English), 50(20), 4671-4674 (2011-04-08)
Sudipta Chatterjee et al.
Carbohydrate polymers, 123, 432-442 (2015-04-07)
Fish oil-loaded microcapsules were prepared from oil-in-water emulsions using N-stearoyl O-butylglyceryl chitosan as shell material. The emulsions were prepared by both membrane and ultrasonic emulsification processes under variable conditions to examine the effect of the emulsification process and encapsulation conditions
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