22612-69-7Relevant academic research and scientific papers
Kinetic Resolution of Neopentylic Secondary Alcohols by Cu-H-Catalyzed Enantioselective Silylation with Hydrosilanes
Oestreich, Martin,Papadopulu, Zaneta
supporting information, p. 438 - 441 (2021/01/13)
A nonenzymatic kinetic resolution of sterically congested alcohols having a quaternary carbon atom in the β-position is reported. The catalyst system CuCl/NaOtBu/(R,R)-Ph-BPE together with a 3,5-xylyl-substituted tertiary hydrosilane enable enantioselective silylation of the hydroxy group. Several alcohols are obtained with good to excellent selectivity factors, and there are no other known straightforward methods to access these motifs.
Synthesis of α-Arylated Cycloalkanones from Congested Trisubstituted Spiro-epoxides: Application of the House-Meinwald Rearrangement for Ring Expansion
Jeedimalla, Nagalakshmi,Jacquet, Camille,Bahneva, Diana,Youte Tendoung, Jean-Jacques,Roche, Stéphane P.
, p. 12357 - 12373 (2018/09/06)
A three-step sequence for the synthesis of α-arylated cyclohexanones and the most challenging cycloheptanones is reported. First, an efficient one-pot synthesis of β,β'-disubstituted benzylidene cycloalkanes (styrenes) using the palladium-catalyzed Barluenga reaction from readily available feedstock chemicals is described. Furthermore, an epoxidation followed by the House-Meinwald rearrangement (HMR) of spiro-epoxides is reported to produce a number of α-arylated cycloalkanones upon ring expansion. Reactions catalyzed by bismuth triflate underwent quasi-exclusively ring expansion for all substrates (electronically poor and rich), with yields ranging from 15% to 95%, thus demonstrating the difficulty of achieving ring enlargement for electron-deficient spiro-epoxides. On the other hand, by means of catalysis with aluminum trichloride, the rearrangement of spiro-epoxides proceeded typically in high yields and with remarkable regioselectivity on a broader substrate scope. In this case, a switch of regioselectivity was achieved for spiro-epoxides with electron-withdrawing substituents which enable the method to be successfully extended to some chemospecific arene shifts and the synthesis of aldehydes bearing a α-quaternary carbon. While the HMR has been extensively studied for smaller ring enlargement, we are pleased to report herein that larger cyclohexanones and cycloheptanones can be obtained efficiently from more sterically demanding trisubstituted spiro-epoxides bearing electron-releasing and electron-neutral arene substituents.
Br?nsted Acid-Catalyzed Intramolecular Hydroarylation of β-Benzylstyrenes
Cai, Xiao,Keshavarz, Amir,Omaque, Justin D.,Stokes, Benjamin J.
, p. 2626 - 2629 (2017/05/24)
Using triphenylmethylium tetrakis(pentafluorophenyl)borate as a convenient Br?nsted acid precatalyst, β-(α,α-dimethylbenzyl)styrenes are shown to cyclize efficiently to afford a variety of new indanes that possess a benzylic quaternary center. The geminal dimethyl-containing quaternary center is proposed to be necessary to arm the substrate for cyclization through steric biasing.
Selective Aerobic Oxidation of Primary Alcohols to Aldehydes
Shibuya, Masatoshi,Furukawa, Keisuke,Yamamoto, Yoshihiko
, p. 1554 - 1557 (2017/08/11)
The 2-azaadamantane- N -oxyl (AZADO)- and 9-azanoradamantane- N -oxyl (nor-AZADO)-catalyzed selective oxidation of primary alcohols to the corresponding aldehydes is described. The use of tert -butyl nitrite as the co-catalyst enables efficient aerobic oxidation in MeCN instead of previously reported AcOH; this is important for the selectivity of the reaction. The addition of a solution of saturated aqueous NaHCO 3 after the completion of the reaction was effective to suppress the overoxidation of the product to the corresponding carboxylic acid during the workup.
PYRIMIDONE DERIVATIVES AND THEIR USE IN THE TREATMENT, AMELIORATION OR PREVENTION OF A VIRAL DISEASE
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, (2014/07/22)
The present invention relates to a compound having the general formula (I), optionally in the form of a pharmaceutically acceptable salt, solvate, polymorph, codrug, cocrystal, prodrug, tautomer, racemate, enantiomer, or diastereomer or mixture thereof, which are useful in treating, ameloriating or preventing a viral disease. Furthermore, specific combination therapies are disclosed.
Fe-catalyzed regiodivergent [1,2]-shift of α-aryl aldehydes
Gutierrez-Bonet, Alvaro,Flores-Gaspar, Areli,Martin, Ruben
supporting information, p. 12576 - 12579 (2013/09/23)
An Fe-catalyzed conversion of aldehydes to ketones via [1,2]-shift has been developed. This skeletal rearrangement shows a wide substrate scope and chemoselectivity profile while exhibiting an excellent [1,2]-aryl or [1,2]-alkyl shift selectivity that is easily switched by electronic effects.
CF3CO2ZnEt-mediated highly regioselective rearrangement of bromohydrins to aldehydes
Wang, Zhihui,Li, Meiyi,Zhang, Wenqin,Jia, Jiangnan,Wang, Fei,Xue, Song
, p. 5968 - 5971 (2011/11/29)
A highly efficient and selective rearrangement reaction of bromohydrins to aldehydes mediated by CF3CO2ZnEt was described. The secondary and tertiary aldehydes were prepared under mild conditions in good to excellent yields (85-99%). The scope and limitations of this rearrangement process were also investigated.
