920-39-8Relevant articles and documents
Disposable cartridge concept for the on-demand synthesis of turbo Grignards, Knochel–Hauser amides, and magnesium alkoxides
Adamo, Andrea,Berton, Mateo,McQuade, D. Tyler,Sheehan, Kevin
supporting information, p. 1343 - 1356 (2020/07/10)
Magnesium organometallic reagents occupy a central position in organic synthesis. The freshness of these compounds is the key for achieving a high conversion and reproducible results. Common methods for the synthesis of Grignard reagents from metallic magnesium present safety issues and exhibit a batch-to-batch variability. Tubular reactors of solid reagents combined with solution-phase reagents enable the continuous-flow preparation of organomagnesium reagents. The use of stratified packed-bed columns of magnesium metal and lithium chloride for the synthesis of highly concentrated turbo Grignards is reported. A low-cost pod-style synthesizer prototype, which incorporates single-use prepacked perfluorinated cartridges and bags of reagents for the automated on-demand lab-scale synthesis of carbon, nitrogen, and oxygen turbo magnesium bases is presented. This concept will provide access to fresh organomagnesium reagents on a discovery scale and will do so independent from the operator’s experience in flow and/or organometallic chemistry.
Iron-Catalyzed Cross-Coupling of Alkynyl and Styrenyl Chlorides with Alkyl Grignard Reagents in Batch and Flow
Deng, Yuchao,Wei, Xiao-Jing,Wang, Xiao,Sun, Yuhan,No?l, Timothy
supporting information, p. 14532 - 14535 (2019/11/21)
Transition-metal-catalyzed cross-coupling chemistry can be regarded as one of the most powerful protocols to construct carbon–carbon bonds. While the field is still dominated by palladium catalysis, there is an increasing interest to develop protocols that utilize cheaper and more sustainable metal sources. Herein, we report a selective, practical, and fast iron-based cross-coupling reaction that enables the formation of Csp?Csp3 and Csp2?Csp3 bonds. In a telescoped flow process, the reaction can be combined with the Grignard reagent synthesis. Moreover, flow allows the use of a supporting ligand to be avoided without eroding the reaction selectivity.
Synthesis, Properties, and Catalytic Application of a Triptycene-Type Borate-Phosphine Ligand
Konishi, Shota,Iwai, Tomohiro,Sawamura, Masaya
, p. 1876 - 1883 (2018/07/05)
A borate-containing caged triarylphosphine L-X (X = Na or NBu4), featuring a 9-phospha-10-boratriptycene framework, was synthesized and characterized by NMR spectroscopy and X-ray diffraction analysis. The NMR coupling constant of the corresponding phosphine selenide indicated a higher electron-donating property of the borate-phosphine L compared to that of the 9-phospha-10-silatriptycene derivative (Ph-TRIP). The coordination property of L-X to [PdCl(η3-allyl)]2 was dependent on the countercation, giving a neutral Pd complex [PdCl(η3-allyl)(L-NBu4)] from L-NBu4 in CH2Cl2 or a zwitterionic Pd complex [Pd(η3-allyl)(MeCN)(L)] from L-Na in MeCN/CH2Cl2. Utility of L-X as a ligand for metal catalysis was demonstrated in the Pd-catalyzed Suzuki-Miyaura cross-coupling of aryl chlorides.
KINASE INHIBITORS AND METHOD OF TREATING CANCER WITH SAME
-
Paragraph 0240, (2014/02/15)
The present teachings provide a compound represented by structural formula (I): or a pharmaceutically acceptable salt thereof. Also described are pharmaceutical compositions and methods of use thereof.
Directional properties of fluorenylidene moieties in unsymmetrically substituted N-heterocyclic carbenes. Unexpected CH activation of a methylfluorenyl group with palladium. Use in palladium catalysed Suzuki-Miyaura cross coupling of aryl chlorides
Teci, Matthieu,Brenner, Eric,Matt, Dominique,Gourlaouen, Christophe,Toupet, Loic
, p. 12251 - 12262 (2014/08/05)
Benzimidazolium salts having their two nitrogen atoms substituted by different 9-alkylfluorenyl groups (4a-e and 4g, alkyl1/alkyl 2 = Me/Et, Me/Pr, Me/n-Bu, Me/i-Pr, Me/Bn, Me/CH2SMe have been synthesised in high yields in two or three steps from N,N′-bis(9H- fluoren-9-ylidene)benzene-1,2-diamine (1). The imidazolium salts 4a-e were converted readily into the corresponding PEPPSI-type palladium complexes (PEPPSI = pyridine-enhanced precatalyst preparation stabilisation and initiation), while reaction of the methylthioether-substituted salt 4g with PdCl 2/K2CO3/pyridine afforded the palladacycle 5g resulting from metallation of the methyl group attached to the fluorenylidene moiety. NMR and X-ray diffraction studies revealed that the carbene ligands in 5a-5e behave as clamp-like ligands, the resulting metal confinement arising from a combination of the orientational properties of the fluorenylidene moieties that push the alkyl groups towards the metal centre and attractive anagostic interactions involving CH2(fluorenyl) groups. Complexes 5a-e were assessed in Suzuki-Miyaura cross-coupling reactions. Like their symmetrical analogues they displayed high activity in the coupling of phenyl boronic acid with p-tolylchloride but their performance remained slightly inferior to that of the related, symmetrical Et/Et complex 5h.
Functionalized α-bromocyclopropylmagnesium bromides: Generation and some reactions
Bolesov,Solov'eva,Baird
, p. 1580 - 1589 (2014/02/14)
Functional derivatives of gem-dibromocyclopropanes (ethers and esters of gemdibromocyclopropylmethanol, 2,2-dibromocyclopropanecarboxylic acids and their esters) undergo partial hydrodebromination at the treatment with isopropyl magnesium bromide (3-6 mol-equiv) in THF and then in methanol at -60°C affording the corresponding monobromides in 64-95% yields. The addition of nonsolvated magnesium bromide to the reaction mixture results in the considerable reduction of the amount of the Grignard reagent (from 6 to 3 mol-equiv). This allows achieving the partial hydrodebromination of 2,2-dibromocyclopropanecarboxylic acids. Pleiades Publishing, Ltd., 2013.
Enantioselective copper-catalysed allylic alkylation of cinnamyl chlorides by Grignard reagents using chiral phosphine-phosphite ligands
Loelsberg, Wibke,Ye, Shute,Schmalz, Hans-Guenther
supporting information; experimental part, p. 2023 - 2031 (2010/10/21)
The copper(I)-catalysed SN2'-type allylic substitution of E-3-aryl-allyl chlorides (cinnamyl chlorides) using Grignard reagents represents a powerful method for the synthesis of compounds carrying a benzylic stereocentre. By screening a small library of modular chiral phosphine-phosphite ligands a new copper(I)-based catalyst system was identified which allows the performance of such reactions with exceptional high degrees of regio- and enantioselectivity. Best results were obtained using TADDOLderived ligands (3 mol%), copper(I) bromide?dimethyl sulfide (CuBr?SMe2) (2.5 mol%) and methyl tert-butyl ether (MTBE) as a solvent. Various (1- alkyl-allyl)benzene derivatives were prepared with up to 99% ee (GC) in isolated yields of up to 99%. In most cases the product contained less than 3% of the linear regioisomer (except for ortho-substituted substrates). Both electron-rich and electron-deficient cinnamyl chlorides were successfully employed. The absolute configuration of the products was assigned by comparison of experimental and calculated CD spectra. The substrates were prepared from the corresponding alcohols by reaction with thionyl chloride. Initially formed mixtures of regioisomeric allylic chlorides were homogenised by treatment with CuBr?SMe2 (2.5 mol%) in the presence of triphenyl phosphine (PPh3) (3 mol%) in MTBE at low temperature to give the pure linear isomers. In reactions with methylmagnesium bromide (MeMgBr) an ortho-diphenylphosphanyl-arylphosphite ligand with an additional phenyl substituent in ortho'-position at the aryl backbone proved to be superior. In contrast, best results were obtained in the case of higher alkyl Grignard reagents (such as ethyl-, n-butyl-, isopropyl-, and 3-butenylmagnesium bromides) with a related ligand carrying an isopropyl substituent in ortho'-position. The method was tested on a multimmol scale and is suited for application in natural product synthesis.
PROCESS FOR PRODUCING EPOXYTRIAZOLE COMPOUND AND INTERMEDIATE THEREFOR
-
Page/Page column 23, (2010/11/23)
The present invention provides a compound of the formula (I); wherein Ar represents difluorophenyl group, which is useful as an intermediate in a process for producing an epoxytriazole compound of the formula (VII); wherein Ar represents difluorophenyl group, which is a synthetic intermediate of antifungal agents. The present invention also provides a process for producing a compound of the formula (VII) which comprises epoxydation step, deprotection step, reaction step with a compound represented by RSO2X, and reaction step with 1,2,4-triazole; or comprises epoxydation step, reaction step with 1,2,4-triazole, deprotection step, reaction step with a compound represented by RSO2X and treatment step by a base.
Method for producing alkyl-bridged ligand systems and transition metal compounds
-
, (2008/06/13)
The invention relates to a method for producing highly substituted alkyl-bridged ligand systems on the basis of indene derivatives and transition metal compounds. Said alkyl-bridged ligand systems can be obtained in high yields using this method.
Substituted oxygen alicyclic compounds, including methods for synthesis thereof
-
, (2008/06/13)
The invention provides new methods for preparation of cyclic oxygen compounds, including 2,5-disubstituted tetahydrofurans, 2,6-disubstituted tetrahydropyrans, 2,7-disubstituted oxepanes and 2,8-oxocanes. The invention also provides new cyclic oxygen compounds and pharmaceutical compositions and therapeutic methods that comprise such compounds.
