22054-13-3Relevant articles and documents
Influence of Some Factors on the Progress of a New Reaction in the Chemistry of Organoaluminum Compounds
Ishmuratov, G. Yu.,Vydrina, V. A.,Yakovleva, M. P.
, p. 1353 - 1358 (2020)
Abstract: We earlier discovered a new reaction in the chemistry of organoaluminum compounds (OACs), specifically, the formation of O-isobutyl acetals on low-temperature (–70°C) treatment of seven-membered lactones with a double (or more) molar amount of diisobutylaluminum hydride (DIBAH) in methylene chloride. To assess the boundaries for the formation of isobutyl acetals depending on the ring size, we involved in the low-temperature hydride reduction six-, eight-, and thirteen-membered lactones. To determine how the scope of the new reaction depends on the nature of the organoaluminum reagent, we tested triisobutylaluminum (TIBA). To determine how the formation of isobutyl acetals on low-temperature (–70°C) reduction with excess DIBAH in CH2Cl2 depends on whether the starting ester is cyclic or acyclic and, if the former is the case, on the ring size in the ester, we used the acyclic methyl octadecanoate as the starting compound. It was found that the new reaction in the chemistry of AOC with DIBAH as the reducer is characteristic only of seven-membered lactones and atypical of acyclic methyl octadecanoate and ricinoleate (i.e. acids with the carbon chain length more than 6).
Photoenzymatic Generation of Unstabilized Alkyl Radicals: An Asymmetric Reductive Cyclization
Clayman, Phillip D.,Hyster, Todd K.
supporting information, p. 15673 - 15677 (2020/10/18)
Flavin-dependent "ene"-reductases can generate stabilized alkyl radicals when irradiated with visible light; however, they are not known to form unstabilized radicals. Here, we report an enantioselective radical cyclization using alkyl iodides as precursors to unstabilized nucleophilic radicals. Evidence suggests this species is accessed by photoexcitation of a charge-transfer complex that forms between flavin and substrate within the protein active site. Stereoselective delivery of a hydrogen atom from the flavin semiquinone to the prochiral radical formed after cyclization provides high levels of enantioselectivity across a variety of substrates. Overall, this transformation demonstrates that photoenzymatic catalysis can address long-standing selectivity challenges in the radical literature.
Tandem rhodium-catalyzed hydroformylation-hydrogenation of alkenes by employing a cooperative ligand system
Fuchs, Daniela,Rousseau, Geraldine,Diab, Lisa,Gellrich, Urs,Breit, Bernhard
supporting information; experimental part, p. 2178 - 2182 (2012/04/10)
Dual action: A multifunctional rhodium catalyst system enables the simultaneous catalysis of two distinct transformations, hydroformylation of an alkene and reduction of an aldehyde, in a highly selective manner. This one-pot/two-step process is controlled by the cooperative action of two different supramolecular ligand systems and transforms terminal alkenes into C1-chain-elongated linear alcohols. Copyright
