On the Ring-opening Reactions of the Furan Compounds. IV. The Condensation Products of Furfural with Methyl Propyl Ketone, Methyl Isopropyl Ketone and Pinacolin by Alkali
作者:Hiroshi Midorikawa
DOI:10.1246/bcsj.27.143
日期:1954.3
Methylpropylketone condensed with furfural by alkali both at the α-methyl and α-methylene groups of the ketone, giving 1-(2-furyl)-1-hexen-3-one (I) in a larger proportion and 3-ethyl-4-(2-furyl)-3-buten-2-one (II) in a much smaller proportion. The former furfurylidene ketone (I) gave γ, ζ-dioxocapric acid (III) on the ring-opening in alcoholic hydrochloric acid, and the latter (II) was oxidized
Asymmetric construction of spirocyclohexanonerhodanines catalyzed by simple diamine derived from chiral tert-leucine
作者:Wenbin Wu、Huicai Huang、Xiaoqian Yuan、Kailong Zhu、Jinxing Ye
DOI:10.1039/c2cc34321e
日期:——
A diamine-catalyzed asymmetric tandem reactionbetweenalpha,beta-unsaturatedketones and rhodanine derivatives has been developed to synthesize various spirocyclic compounds with high stereoselectivities (up to 99% ee and >20:1 dr). The products obtained contain two pharmaceutically relevant features: the biologically active rhodanine moiety embedded in a spirocyclic unit.
On the Ring-opening Reactions of the Furan Compounds. III. On the Condensation of Furfural with Methyl Ethyl Ketone by Alkali
作者:Hiroshi Midorikawa
DOI:10.1246/bcsj.26.460
日期:1953.8
furfural can react with methylethylketone in two ways by alkali. In the condensation at 0∼3°, the main product was 4-(2-furyl)-3-methyl-4-butanol-2-one. This aldol was easily dehydrated to 4-(2-furyl)-3-methyl-3-buten-2-one, which was oxidised to α-methyl-2-furanacrylic acid by sodium hypochlorite. In the condensation at 60∼3°, the main product was the furfurylidene ketone, which gave the semicabazone
Ligand-Enabled γ-C(sp<sup>3</sup>)–H Hydroxylation of Free Amines with Aqueous Hydrogen Peroxide
作者:Zhen Li、Jin-Quan Yu
DOI:10.1021/jacs.3c09340
日期:2023.12.6
of primary amines (1°), piperidines, and morpholines (2°) were hydroxylated at the γ-position with excellent monoselectivity. This method provides an avenue for the synthesis of a wide range of amines, including γ-amino alcohols, β-amino acids, and azetidines. The retention of chirality in the reaction allows rapid access to chiral amines starting from the abundant chiral amine pool.