7500-73-4Relevant articles and documents
Hydrogen borrowing catalysis using 1° and 2° alcohols: Investigation and scope leading to α and β branched products
Frost, James R.,Cheong, Choon Boon,Akhtar, Wasim M.,Caputo, Dimitri F.J.,Christensen, Kirsten E.,Stevenson, Neil G.,Donohoe, Timothy J.
, (2021/04/07)
The alkylation of a variety of ketones using 1° or 2° alcohols under hydrogen borrowing catalysis is described. Initial research focused on the α-alkylation of cyclopropyl ketones with higher 1° alcohols (i.e. larger than MeOH), leading to the formation of α-branched products. Our search for additional substrates with which to explore this chemistry led us to discover that di-ortho-substituted aryl ketones were also privileged scaffolds, with Ph? (C6Me5) ketones being the optimal choice. Further investigations revealed that this motif was crucial for alkylation with 2° alcohols forming β-branched products, which also provided an opportunity to study diastereoselective and intramolecular hydrogen borrowing processes.
Cross β-arylmethylation of alcohols catalysed by recyclable Ti-Pd alloys not requiring pre-activation
Utsunomiya, Masayoshi,Kondo, Ryota,Oshima, Toshinori,Safumi, Masatoshi,Suzuki, Takeyuki,Obora, Yasushi
supporting information, p. 5139 - 5142 (2021/05/31)
Ti-Pd alloy catalysts were developed for the cross β-arylmethylation between arylmethylalcohols and different primary alcohols via a hydrogen autotransfer mechanism. The alloy catalysts could be reused multiple times without the need for pre-activation. Analysis of the reaction solution by inductively coupled plasma atomic absorption spectroscopy indicated that only a minimal amount of Ti and no Pd was leached from the catalyst.
Enantioselective Formal α-Methylation and α-Benzylation of Aldehydes by Means of Photo-organocatalysis
Filippini, Giacomo,Silvi, Mattia,Melchiorre, Paolo
supporting information, p. 4447 - 4451 (2017/04/13)
Detailed herein is the photochemical organocatalytic enantioselective α-alkylation of aldehydes with (phenylsulfonyl)alkyl iodides. The chemistry relies on the direct photoexcitation of enamines to trigger the formation of reactive carbon-centered radicals from iodosulfones, while the ground-state chiral enamines provide effective stereochemical control over the radical trapping process. The phenylsulfonyl moiety, acting as a redox auxiliary group, facilitates the generation of radicals. In addition, it can eventually be removed under mild reducing conditions to reveal methyl and benzyl groups.