59376-64-6Relevant academic research and scientific papers
Hydromagnesiation of 3-Trimethylsilylprop-2-yn-1-ol. A Simple Route to (E)-3-Trimethylsilylalk-2-en-1-ols
Sato, Fumie,Watanabe, Hiroshi,Tanaka, Youichi,Sato, Masao
, p. 1126 - 1127 (1982)
Hydromagnesiation of 3-trimethylsilylprop-2-yn-1-ol affords the alkenylmagnesium halide (3) exclusively, which is valuable as a precursor of various (E)-3-trimethylsilylalk-2-en-1-ols.
Ambruticins: tetrahydropyran ring formation and total synthesis
Bowen, James I.,Crump, Matthew P.,Wang, Luoyi,Willis, Christine L.
supporting information, p. 6210 - 6215 (2021/07/28)
The ambruticins are a family of polyketide natural products which exhibit potent antifungal activity. Gene knockout experiments are in accord with the proposal that the tetrahydropyran ring of the ambruticins is formedviathe AmbJ catalysed epoxidation of the unsaturated 3,5-dihydroxy acid, ambruticin J, followed by regioselective cyclisation to ambruticin F. Herein, a convergent approach to the total synthesis of ambruticin J is described as well as model studies involving epoxidation and cyclisations of unsaturated hydroxy esters to give tetrahydropyrans and tetrahydrofurans. The total synthesis involves preparation of three key fragments which were unitedviaa Suzuki-Miyaura cross-coupling and Julia-Kocienski olefination to generate the required carbon framework. Global deprotection to a triol and selective oxidation of the primary alcohol gave, after hydrolysis of the lactone, ambruticin J.
Exploring the scope of tandem palladium and isothiourea relay catalysis for the synthesis of α-amino acid derivatives
Bitai, Jacqueline,Slawin, Alexandra M.Z.,Cordes, David B.,Smith, Andrew D.
supporting information, (2020/07/27)
The scope and limitations of a tandem N-allylation/[2,3]-rearrangement protocol are investigated through the incorporation of a variety of functional groups within an allylic phosphate precursor. This method uses readily accessible N,N-dimethylglycine aryl esters and functionalized allylic phosphates, forming quaternary ammonium salts in situ in the presence of a palladium catalyst. Subsequent enantioselective [2,3]-sigmatropic rearrangement, promoted by the chiral isothiourea tetramisole, generates α-amino acid derivatives with two contiguous stereocenters. The incorporation of electron-withdrawing ester and amide groups gave the best results, furnishing the desired products in moderate to good yields (29-70percent), with low diastereocontrol (typically 60:40 dr) but high enantioselectivity (up to 90:10 er). These results indicate that substrate-catalyst interactions in the proposed transition state are sensitive to the substitution pattern of the substrates.
An Aliphatic Bischler-Napieralski Reaction: Dihydropyridones by Cyclocarbonylation of 3-Allylimidazolidin-4-ones
Amer, Mostafa M.,Olaizola, Olatz,Carter, Jennifer,Abas, Hossay,Clayden, Jonathan
supporting information, p. 253 - 256 (2020/01/02)
The N-chloroformylimidazolidinone derivative of enantiopure l-alanine was deprotonated to form an enolate and functionalized with a series of allylic halides. Treatment of the resulting carbamoyl chlorides with potassium iodide led to cyclization of the allylic substituent onto the carbonyl group in an intramolecular aliphatic Friedel-Crafts-type acylation that corresponds to an aliphatic Bischler-Napieralski reaction. The product 3,4-dihydropyridinones were amenable to further functionalization, and finally hydrolysis, to deliver a series of enantio-enriched pipecolic acid derivatives.
Synthesis of multinuclear Rh(I) complexes bearing triazolylidenes and their application in C-C and c-Si bond forming reactions
Mendoza-Espinosa, Daniel,Rendón-Nava, David,Vásquez-Pérez, Jose M.,Sandoval-Chávez, Cesar I.,Alvarez-Hernández, Alejandro
, p. 3961 - 3971 (2020/12/01)
Multidentate carbene ligands are valuable frameworks for the preparation of carbene complexes displaying higher nuclearity. In the present work, we report the synthesis of a series of mono- to tetra-[Rh(COD)I] complexes (3a- d) supported by mesoionic triazol-5-ylidenes. The general synthetic procedure involves the one step reaction of the appropriate triazolium (2a-d) salt in the presence of KHMDS and stoiquiometric amounts of the rhodium(I) precursor. Treatment of complexes 3a-d with an excess of carbon monoxide allows for the quantitative preparation of complexes 4a-d featuring a [Rh(CO)2I] fragment used for the detemination of the donor properties of the new triazolylidene ligands. All complexes have been fully characterized by means of 1H and 13C NMR spectroscopy, melting point, elemental analysis, and in the case of complex 3a, by X-ray crystallography. Comparison of the catalytic activity of the new rhodium complexes in C-C and C-Si bond forming processes demonstrate the enhanced performance of the tetranuclear species suggesting the possibility of strong cooperative effects in these multinuclear complexes.
Nickel-Catalyzed Direct Coupling of Allylic Alcohols with Organoboron Reagents
Wang, Gaonan,Gan, Yi,Liu, Yuanhong
supporting information, p. 916 - 920 (2018/09/22)
The direct coupling of allylic alcohols with arylboronic acids or their derivatives catalyzed by Ni(cod)2 in the presence of a catalytic amount of base has been developed. A wide variety of allylic substrates or arylboronic acids turned out to be applicable to this catalytic system. The present method does not require the use of ligands for stabilizing the nickel catalyst in most cases or additional activators for activation of allylic alcohols.
Si-directed regiocontrol in asymmetric Pd-catalyzed allylic alkylations using C1-ammonium enolate nucleophiles
Fyfe, James W.B.,Kabia, Omaru M.,Pearson, Colin M.,Snaddon, Thomas N.
supporting information, p. 5383 - 5391 (2018/04/23)
Cooperative catalysis enables the direct enantioselective α-allylation of linear prochiral esters using Si-substituted allyl electrophiles. The Si-substituent directs the regioselectivity of enantioselective bond formation and provides products containing synthetically versatile pentafluorophenyl ester and vinylsilane moieties. Critical to the efficacy of this process was the recognition that the ancillary ligand on palladium could be altered to prevent formation of a deleterious ether by-product, whilst retaining enantioselectivity through the Lewis base catalyst. Flexibility such as this is unique to cooperative catalysis events and provides efficient access to an array of enantioenriched products that are orthogonally functionalized and easily modified.
Synthesis method of methylcyclopropene probe
-
Paragraph 0019-0020, (2017/04/05)
The invention discloses a synthesis method of a methylcyclopropene probe, and belongs to the technical field of small organic molecule fluorescent probes. The method includes the steps that 3-(trimethylsilyl)-2-propyn-1-ol serves as the raw material and i
Asymmetric synthesis of 12-hydroxyheptadecatrienoic acid and its 5,6-dihydro- and 14,15-dehydro-derivatives
Kobayashi, Yuichi,Morita, Masao,Ogawa, Narihito,Kondo, Daiki,Tojo, Toshifumi
supporting information, p. 10667 - 10673 (2016/11/30)
Natural 12-hydroxyheptadecatrienoic acid (12-HHT) with an S configuration was synthesised by a Suzuki-Miyaura coupling of C10-C17 iodo alcohol with C1-C9 vinylborane. The iodo alcohol was synthesised by utilising Sharpless asymmetric epoxidation of the corresponding trimethylsilyl alcohol. The method yielded more than 100 mg of 12-HHT. Similarly, syntheses of 5,6-dihydro- and 14,15-dehydro derivatives of 12-HHT, known as HHD and HHTE, respectively, were completed in a stereoselective manner.
A new protocol for nickel-catalysed regio- and stereoselective hydrocyanation of allenes
Arai, Shigeru,Hori, Hiroto,Amako, Yuka,Nishida, Atsushi
supporting information, p. 7493 - 7496 (2015/05/04)
Regio- and stereoselective hydrocyanation under nickel catalysis is described. This report shows that allenyl C-C double bonds are discriminated and converted to the corresponding carbonitriles as a single product. The key functionalities for achieving high regio- and stereocontrol are aryl and cyclopropyl groups in the substrates. This journal is
