22665-13-0Relevant academic research and scientific papers
Nickel-Mediated Enantiospecific Silylation via Benzylic C-OMe Bond Cleavage
Balakrishnan, Venkadesh,Murugesan, Vetrivelan,Chindan, Bincy,Rasappan, Ramesh
supporting information, p. 1333 - 1338 (2021/02/20)
Benzylic stereocenters are found in bioactive and drug molecules, as enantiopure benzylic alcohols have been used to build such a stereogenic center, but are limited to the construction of a C-C bond. Silylation of alkyl alcohols has the potential to build bioactive molecules and building blocks; however, the development of such a process is challenging and unknown. Herein, we describe an unprecedented AgF-assisted nickel catalysis in the enantiospecific silylation of benzylic ethers.
Time-dependent enantiodivergent synthesis via sequential kinetic resolution
Tu, Hang-Fei,Yang, Pusu,Lin, Zi-Hua,Zheng, Chao,You, Shu-Li
, p. 838 - 844 (2020/07/03)
The preparation of both enantiomers of chiral molecules is among the most fundamental tasks in organic synthesis, medicinal chemistry and materials science. Achieving this goal typically requires reversing the absolute configuration of the chiral component employed in the reaction system that is being used. The task becomes challenging when the natural source of the chiral component is not available in both configurations. Herein, we report a time-dependent enantiodivergent synthesis, in which an Ir-catalysed allylic substitution reaction uses one catalyst sequentially to promote two kinetic resolution reactions, enabling the synthesis of both enantiomers of the product using the same enantiomer of a chiral catalyst. The appropriate permutation of individual reaction rates is essential for the isolation of the chiral products in opposite configurations with high enantiopurity when quenched at different reaction times. This work provides an alternative solution for the preparation of both enantiomers of chiral molecules. [Figure not available: see fulltext.].
Iron-Catalyzed Grignard Cross-Couplings with Allylic Methyl Ethers or Allylic Trimethylsilyl Ethers
Seto, Chika,Otsuka, Takeshi,Takeuchi, Yoshiki,Tabuchi, Daichi,Nagano, Takashi
supporting information, p. 1211 - 1214 (2018/03/26)
We have found that cross-coupling between aryl Grignard reagents and allylic methyl ethers proceeded well in the presence of a catalytic amounts of Fe(acac) 3 to afford the corresponding allylic substitution products in good yields. Under the same conditions, allylic trimethylsilyl ethers also reacted with Grignard reagents to give the corresponding cross-coupling products.
Electrochemical properties and reactions of organoboronic acid esters containing unsaturated bonds at their α-position
Ohtsuka, Kazuhiro,Inagi, Shinsuke,Fuchigami, Toshio
, p. G23 - G28 (2017/12/26)
Electrochemical analyses of 2-(cynnamyl)boronic acid pinacol ester and (3-phenyl-2-propynyl)boronic acid pinacol ester, and their trimethylsilyl analogues as well as their parent compounds were comparatively studied by cyclic voltammetry measurements. We
Pincer-Nickel-Catalyzed Allyl-Aryl Coupling between Allyl Methyl Ethers and Arylzinc Chlorides
Tao, Jian-Long,Yang, Bo,Wang, Zhong-Xia
, p. 12627 - 12634 (2016/01/09)
The P,N,N-pincer nickel complex [Ni(Cl){N(2-Ph2PC6H4)(2′-Me2NC6H4)}]-catalyzed allyl-aryl coupling was studied. The reaction of allyl methyl ethers, including (1-methoxyallyl)arenes and (3-methoxyprop-1-en-1-yl)arenes, with arylzinc chlorides afforded linear (E)-alkenes in high yields, whereas the reaction of (E)-1-methoxytridec-2-ene with p-Me2NC6H4ZnCl generated a mixture of linear and branched alkenes.
Regio- and Enantioselective Allylation of Phenols via Decarboxylative Allylic Etherification of Allyl Aryl Carbonates Catalyzed by (Cyclopentadienyl)ruthenium(II) Complexes and Pyridine-Hydrazone Ligands
Egger, Léo,Tortoreto, Cecilia,Achard, Thierry,Monge, David,Ros, Abel,Fernández, Rosario,Lassaletta, José M.,Lacour, Jér?me
, p. 3325 - 3331 (2015/11/03)
(Cyclopentadienyl)tris(acetonitrile)ruthenium hexafluorophosphate [CpRu(CH3CN)3][PF6] in combination with pyridine-hydrazone ligands efficiently catalyzes the asymmetric decarboxylative allylic rearrangement of allyl aryl carbonates. Formation of C-O bonds with high regio- and enantioselectivity ratios (up to 95:5 and 98% ee) is obtained. Good stereocontrol of the pseudotetrahedral geometry of the CpRu moiety is achieved by the hydrazone ligand and its "electron-poor" nature is evidenced through the epimerization of the hexacoordinated TRISPHAT-N anion.
Iron-catalyzed N-alkylation using π-activated ethers as electrophiles
Fan, Xiaohui,Fu, Lin-An,Li, Na,Lv, Hao,Cui, Xiao-Meng,Qi, Yuan
supporting information, p. 2147 - 2153 (2013/04/10)
A new method for the synthesis of diverse N-alkylation compounds was developed via an iron-catalyzed etheric Csp3-O cleavage with the C-N bond formation in the reaction of π-activated ethers with various nitrogen-based nucleophiles. In addition, the mechanism of this reaction was investigated. The Royal Society of Chemistry 2013.
Reactions of p-coumaryl alcohol model compounds with dimethyl carbonate. Towards the upgrading of lignin building blocks
Stanley, Jessica N. G.,Selva, Maurizio,Masters, Anthony F.,Maschmeyer, Thomas,Perosa, Alvise
, p. 3195 - 3204 (2013/11/06)
Cinnamyl alcohol 1 and 4-(3-hydroxypropyl)phenol 2, two compounds resembling the lignin building block p-coumaryl alcohol, can be selectively transformed into different products by catalytic methodologies based on dimethyl carbonate (DMC) as a green solvent/reagent. Selectivity can be tuned as a function of the reaction temperature and of the nature of the catalyst. Basic catalysts such as K2CO3, trioctylmethylphosphonium methylcarbonate ([P8881][CH3OCOO]), and CsF/αAl 2O3 promote selective transesterification of the aliphatic hydroxyl group at 90 °C. However, amphoteric solids such as alkali metal-exchanged faujasites, NaX and NaY, selectively yield the corresponding alkyl ethers at higher temperatures (165-180 °C). The phenolic hydroxyl group of 2 can be methylated similarly with the faujasites at high temperatures. This preliminary screening for selectivity illustrates reactivity trends and delineates some of what might be among the most promising synthetic pathways to upgrade lignin-derived chemical building blocks.
(Cyclopentadienyl)ruthenium-catalyzed regio- and enantioselective decarboxylative allylic etherification of allyl aryl and alkyl carbonates
Austeri, Martina,Linder, David,Lacour, Jerome
scheme or table, p. 3339 - 3347 (2011/02/23)
(Cyclopentadienyl)tris(acetonitrile)ruthenium hexafluorophosphate {[CpRu(NCMe)3][PF6] or (cyclopentadienyl) (I·6-naphthalene)ruthenium hexafluorophosphate {[CpRu(I·6-naphthalene)][PF6]} in combination with a pyridine oxazoline ligand efficiently catalyze the decarboxylative allylic rearrangement of allyl aryl carbonates. Good levels of regio- and enantioselectivity are obtained. Starting from enantioenriched secondary carbonates, the reaction is stereospecific and the corresponding allylic ethers are obtained with net retention of configuration. An intermolecular version of this transformation was also developed using allyl alkyl carbonates as substrates. Conditions were found to obtain the corresponding products with similar selectivity as in the intramolecular process. Through the use of a hemi-labile hexacoordinated phosphate counterion, a zwitterionic air- and moisture-stable chiral ruthenium complex was synthesized and used in the enantioselective etherification reactions. This highly lipophilic metal complex can be recovered and efficiently reused in subsequent catalysis runs. Copyright
Absolute reactivity of arylallyl carbocations
Hallett-Tapley, Geniece,Cozens, Frances L.,Schepp, Norman P.
experimental part, p. 343 - 348 (2010/04/30)
A series of α-vinyl arylmethyl cations were generated and studied using nanosecond laser flash photolysis. Rate constants for the decay of the substituted α-vinyl arylmethyl cations were determined under solvolytic conditions in pure solvents and solvent
