930-59-6Relevant academic research and scientific papers
Use of the 2-Pyridinesulfonyloxy Leaving Group for the Fast Copper-Catalyzed Coupling Reaction at Secondary Alkyl Carbons with Grignard Reagents
Shinohara, Riku,Morita, Masao,Ogawa, Narihito,Kobayashi, Yuichi
, p. 3247 - 3251 (2019/05/10)
Investigation of the copper-catalyzed coupling reaction of 2-pyridinesulfonates with Grignard reagents revealed that reactions with catalytic Cu(OTf)2 were completed in 40 min. The results differed from those of the previous CuI-catalyzed reactions of tosylates in the presence of additives (LiOMe and TMEDA) for 12-24 h. It was shown that the preferred coordination of the leaving group to the reagents accelerated the reaction. Successful reagents were MeMgCl and other RMgX. Complete inversion was established.
The Stereoselective Reductions of Ketones to the Most Thermodynamically Stable Alcohols Using Lithium and Hydrated Salts of Common Transition Metals
Kennedy, Nicole,Cohen, Theodore
, p. 8134 - 8141 (2015/09/02)
A simple method is presented for the highly stereoselective reductions of ketones to the most thermodynamically stable alcohols. In this procedure, the ketone is treated with lithium dispersion and either FeCl2·4H2O or CuCl2·2H2O in THF at room temperature. This protocol is applied to a large number and variety of ketones and is both more convenient and efficient than those commonly reported for the diastereoselective reduction of five- and six-membered cyclic ketones.
Transfer Hydrogenation of Ketones with (1-) as the Precatalyst
Bhaduri, Sumit,Sharma, Krishna,Mukesh, Doble
, p. 1191 - 1200 (2007/10/02)
The cluster 1a has been found to be an efficient precatalyst for the transfer hydrogenations of ketones and α,β-unsaturated ketones.With substrates such as (5S)-carvone , (3R)-methylcyclopentanone and (3R)-methylcyclohexanone, moderate to high diastereoselectivities were observed for reduction of the conjugated olefinic and ketonic functionalities respectively.Aromatisation of carvone to 5-isopropyl-2-methylphenol and disproportionation of cyclohex-2-en-1-one to phenol and cyclohexanone have also been found to be catalysed by 1a.Studies with radical inhibitors and other evidence suggest a radical mechanism for the transfer-hydrogenation and aromatisation reactions.In the transfer hydrogenation of cyclohex-2-en-1-one, the rate of conversion of 1a into other soluble species can be modelled accurately if autocatalysis is assumed.The time-dependent concentration profiles of cyclohex-2-en-1-one, cyclohexanone and cyclohexanol are simulated well if autocatalytic formation of an active intermediate followed by consecutive reactions leading to the formation of products is assumed.Such a model is also consistent with the proposed radical mechanism.
Use of Shift Reagent with MTPA Derivatives in 19F NMR Spectroscopy IV - Determination of Enantiomeric Composition for a Variety of Secondary Cycloalkanols. A Survey
Merckx, E. M.,Lepoivre, J. A.,Lemiere, G. L.,Alderweireldt, F. C.
, p. 380 - 387 (2007/10/02)
Chiral secondary cycloalkanols (monpocyclic alcohols) are derivatized to the corresponding (R)-α-methoxy-α-trifluoromethyl-α-phenylacetic acid esters and analysed by 19F NMR in the presence of tris(6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionato)europium(III) .Using this method the enantiomeric composition can be measured for severak cyclopentanols, cyclohexanols and cycloheptanols, with a variety of substitution patterns.It is shown that a mixture of four stereoisomeric cycloalkanols, such as cis and trans disubstituted alcohols, can be analysed simultaneously.
