767-54-4Relevant articles and documents
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Peppiatt,Wicker
, p. 3122 (1955)
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Reaction of Lithium Aluminum Hydride with Hindered Phenols. Formation of Tricoordinate Aluminum Species
Haubenstock, Howard,Mester, Theodore A.,Zieger, Herman
, p. 3443 - 3448 (1980)
Lithium aluminum hydride reacts readily with 3 molar equiv of 2,4,6-tri-tert-butylphenol in refluxing ether.It has been demonstrated that the products resulting from this reaction cause the conversion of axial to equatorial cyclohexanols in the presence of a ketone.This behaviour is attributed to the formation of tricoordinate aluminum species.An ether solution of bis(2,4,6-tri-tert-butylphenoxy)aluminum hydride was prepared, and infrared spectra provide evidence for the existence of this species in solution resulting from the reaction of LiAlH4 with 3 molar equiv of 2,4,6-tri-tert-butylphenol.
On the Reaction of Lithium Aluminum Hydride with Alcohols
Haubenstock, H.,Mester, T.
, p. 945 - 948 (1983)
Infrared spectra of the reaction products of lithium aluminum hydride (LiAlH4) with 3 molar equiv of isobutyl alcohol, 2-propanol, and the more sterically hindered 2,4-dimethyl-3-pentanol, 4, in diethyl ether were examined.Alcohol 4 reacts with LiAlH4 in diethyl ether, giving a clear solution that is highly stereoselective in the reduction of 3,3,5-trimethylcyclohexanone, 1.The reaction of LiAlH4 with 4 does not lead to tricoordinate aluminum species.On the basis of infrared spectra and the stereochemistry of reduction of 1, it is concluded that LiAlH4 is presentin solution after its reaction with 3 molar equiv of isobutyl alcohol.LiAlH4 is also the initial reducing species in solution after reaction with 2-propanol.On the other hand, LiAlH4 reacts with methanol, ethanol, and 4, giving lithium alkoxyaluminum hydride species.Possible pathways for the reaction of LiAlH4 with alcohols are discussed.
Heterogeneous Hydroxyl-Directed Hydrogenation: Control of Diastereoselectivity through Bimetallic Surface Composition
Shumski, Alexander J.,Swann, William A.,Escorcia, Nicole J.,Li, Christina W.
, p. 6128 - 6134 (2021/05/29)
Directed hydrogenation, in which product selectivity is dictated by the binding of an ancillary directing group on the substrate to the catalyst, is typically catalyzed by homogeneous Rh and Ir complexes. No heterogeneous catalyst has been able to achieve equivalently high directivity due to a lack of control over substrate binding orientation at the catalyst surface. In this work, we demonstrate that Pd-Cu bimetallic nanoparticles with both Pd and Cu atoms distributed across the surface are capable of high conversion and diastereoselectivity in the hydroxyl-directed hydrogenation reaction of terpinen-4-ol. We postulate that the OH directing group adsorbs to the more oxophilic Cu atom while the olefin and hydrogen bind to adjacent Pd atoms, thus enabling selective delivery of hydrogen to the olefin from the same face as the directing group with a 16:1 diastereomeric ratio.
Selective reduction of organic compounds with Al- trifluoromethanesulfonyldiisobutylalane. Comparison of its reactivity with Al-methanesulfonyldiisobutylalane
Cha, Jin Soon
experimental part, p. 219 - 224 (2011/11/06)
The new MPV type reagent, Al-trifluoromethanesulfonyldiisobutylalane (DIBAO3SCF3), has been prepared and its reducing characteristics in the reduction of selected organic compounds containing representative functional groups have been examined, and compared its reactivity with that of Al-methanesulfonyldiisobutylalane (DIBAO3SCH 3) in order to understand the fluorine-substituent effect on its reactivity. In general, the reactivity of DIBAO3SCF3 appears to be much higher than that of DIBAO3SCH3, apparently due to the acidity increase by the electron-withdrawing fluorine-substituent. The reagent reduced aldehydes and ketones readily, but showed a perfect selectivity in the reduction of α,β-unsaturated aldehydes and ketones to produce the corresponding allylic alcohols in an absolutely 100% purity. In addition, the reagent achieved the regioselective cleavage of phenyl-or/and alkyl-substituted epoxides to the less substituted alcohols in a perfect regioselectivity. Moreover, the reagent also showed an high stereoselectivity in the reduction of substituted cycloalkanones to produce the thermodynamically more stable alcohol epimers exclusively.
Al-isopropoxydiisobutylalane: A study of the effect of solvent on the rate and stereoselectivity of cyclic ketone reduction
Bahia, Perdip S.,Jones, Matthew A.,Snaith, John S.
, p. 9289 - 9291 (2007/10/03)
The effect of solvent on the rate and stereoselectivity of cyclic ketone reduction by Al-isopropoxydiisobutylalane (DIBAiOPr) has been investigated. In dichloromethane, DIBAiOPr behaves as a bulky reducing agent, approaching the carbonyl group along an equatorial trajectory to produce the axial alcohol with > 10:1 stereoselectivity. In sharp contrast, reduction in toluene gives the complementary outcome, affording the thermodynamically more stable isomer with > 99:1 stereoselectivity.
