Showing papers by "Masahiro Murakami published in 2020"
TL;DR: These reactions provide a straightforward pathway from readily available materials leading to valued structural motifs of pharmacological relevance.
Abstract: A photoinduced dehydrogenative coupling reaction between benzylic and aldehydic C-H bonds is reported. When a solution of an alkylbenzene and an aldehyde in ethyl acetate is irradiated with visible light in the presence of iridium and nickel catalysts, a coupled α-aryl ketone is formed with evolution of dihydrogen. An analogous C-C bond forming reaction occurs between a C-H bond next to the nitrogen of an N-methylamide and an aldehydic C-H bond to produce an α-amino ketone. These reactions provide a straightforward pathway from readily available materials leading to valued structural motifs of pharmacological relevance.
95 citations
TL;DR: A convenient method to specifically acylate phenolic hydroxyl groups through a radical pathway through the presence of iridium and nickel bromide catalysts to furnish an ester.
Abstract: A convenient method is reported to specifically acylate phenolic hydroxyl groups through a radical pathway. When a mixture of an aldehyde and a phenol in ethyl acetate is irradiated with blue light in the presence of iridium and nickel bromide catalysts at ambient temperature, phenoxyl and acyl radicals are transiently generated in situ and cross-couple to furnish an ester. Aliphatic hydroxy groups remain untouched under the reaction conditions.
28 citations
TL;DR: Unprotected aldoses in water undergo an isomerization reaction via a radical pathway when irradiated with light in the presence of water-soluble benzophenone, which generates 2-deoxy lactones, which are often contained in bioactive compounds.
Abstract: Unprotected aldoses in water undergo an isomerization reaction via a radical pathway when irradiated with light in the presence of water-soluble benzophenone. Whereas its anomeric carbon (C1) is oxidized to a carboxy group, the hydroxy group on the C2 carbon is replaced by hydrogen. The generated 2-deoxy lactones are readily reduced to the corresponding 2-deoxy aldoses, which are often contained in bioactive compounds.
25 citations
TL;DR: A Rh(II)-catalyzed reaction between 1-tosyl-1,2,3-triazoles and halohydrins to provide 2,6-substituted 3,4-dihydro-2H-1-4-oxazines under basic conditions is reported.
16 citations
TL;DR: Herein reported is a dehydrative coupling reaction of alkyl amines with allylic alcohols promoted by co-operation of photoredox and palladium catalysts promoting a range of homoallylic amines efficiently synthesized.
14 citations
TL;DR: An enantioselective Rh(II)-catalyzed cyclooligomerization reaction of thiophenes having triazolyl and vinyl substituents at the 2- and 4-positions is studied and Structurally interesting cyclic trimers whose chirality is ascribed only to the orientation of the 2,4-disubstituted thiophene rings are obtained.
Abstract: An chiral RhII -catalyzed cyclooligomerization reaction of thiophenes having triazolyl and vinyl substituents at the 2- and 4-positions was studied. Structurally interesting cyclic trimers, having chirality that is ascribed only to the orientation of the 2,4-disubstituted thiophene rings, are obtained. The 2,4-disubstitution of the starting thiophene monomer allows production of each of the enantiomers. The observed electronic circular-dichroism spectra are in accord with those simulated by density-functional theory calculations.
11 citations
TL;DR: In this paper, a dehydrative allylation reaction of 2-alkylbenzophenones with allylic alcohols promoted by light and palladium was reported, and the reaction was shown to generate nucleophilic s...
Abstract: Herein reported is a dehydrative allylation reaction of 2-alkylbenzophenones with allylic alcohols promoted by light and palladium. Photoirradiation of 2-alkylbenzophenones generates nucleophilic s...
4 citations
TL;DR: In this paper, a new synthetic method for alkyl sulfones through C-C bond formation between alkenes and tosylmethylphosphonium iodide was reported.
Abstract: A new synthetic method for alkyl sulfones through C–C bond formation between alkenes and tosylmethylphosphonium iodide is reported. A tosylmethyl radical is generated from the phosphonium iodide un...
1 citations
1 citations
TL;DR: Herein reported is a photoredox-catalyzed oxidative degradation reaction of unprotected aldohexonic acids, which are shortened by one-carbon to the corresponding aldopentoses.
Abstract: Herein reported is a photoredox-catalyzed oxidative degradation reaction of unprotected aldohexonic acids, which are shortened by one-carbon to the corresponding aldopentoses Oxygen including aeri
1 citations