698-76-0Relevant articles and documents
Photo-induced radical borylation of hemiacetals via C–C bond cleavage
Liu, Qianyi,Zhang, Jianning,Zhang, Lei,Mo, Fanyang
supporting information, (2021/01/05)
In this study, we reported a photo-induced radical borylation of hemiacetal derivatives via C–C bond cleavage. This transformation can be realized under mild conditions with simple reaction settings and irradiation of visible light. A series of substrates, including both cyclic and linear hemiacetal derivatives, were effectively transformed to the borylation product in moderate to good yields. Finally, the mechanism was studied in detail by DFT calculations, suggesting insight of the radical borylation process.
New strategies in carbonylation chemistry: The synthesis of δ-lactones from saturated alcohols and CO
Tsunoi, Shinji,Ryu, Ilhyong,Okuda, Tohru,Tanaka, Minoru,Komatsu, Mitsuo,Sonoda, Noboru
, p. 8692 - 8701 (2007/10/03)
This paper describes the δ-carbonylation of saturated alcohols which uses a 1,5-hydrogen-transfer reaction of alkoxyl radicals and subsequent carbonylation at the δ-carbon atoms as the key. The carbonylation reactions of five classes of saturated alcohols, namely, primary alcohols having primary δ-carbons, primary alcohols having secondary δ-carbons, primary alcohols having tertiary δ-carbons, secondary alcohols having primary δ- carbons, secondary alcohols having secondary δ-carbons, were carded out, in which lead tetraacetate (LTA) was used as a one-electron oxidant to generate the alkoxyl radicals. Carbonylation of these saturated alcohols, except for primary alcohols having tertiary δ-carbons, took place to afford δ-lactones in moderate to good yields. The mechanism of the remote carbonylation likely involves (1) alkoxyl radical generation via LTA oxidation of a saturated alcohol, (2) conversion of this alkoxyl radical to a δ-hydroxyalkyl radical by a 1,5-hydrogen-transfer reaction, (3) CO trapping of the δ-hydroxyalkyl radical yielding an acyl radical, and (4) oxidation and cyclization of the acyl radical to give a δ-lactone. A metal salt-free system was also tested for a substrate derived from a tertiary alcohol having a secondary δ- carbon; the photolysis of an alkyl 4-nitrobenzenesulfenate under CO pressures gave a δ-lactone in moderate yield.
Biosynthesis of the Hypotensive Metabolite Oudenone by Oudemansiella radicata. 1. Intact Incorporation of a Tetraketide Chain Elongation Intermediate
Tsantrizos, Youla S.,Zhou, Fei,Famili, Parsa,Yang, Xianshu
, p. 6922 - 6929 (2007/10/03)
The biosynthesis of the fungal metabolite oudenone (1) was investigated in cultures of Oudemansiella radicata.Feeding experiments using 13C- and 2H-labeled precursors, as well as NMR analyses of the labeled metabolite, suggested a polyketide origin.The incorporation of six acetate units into the carbon skeleton of 1 was observed when cultures were fed the N-acetylcysteamine thioester derivative of 13C-labeled acetate.Labeling of oudenone (1) from succinate or L-glutamic acid was not observed, whereas the pattern of 13C labeling from succinate was identical to that observed with acetate.The proposed advanced intermediate (5S)-5-hydroxyoctanoic acid (2) was synthesized as the deuterium labeled N-acetylcysteamine thioester derivative (S)-19 and successfully incorporated into 1.A biosynthetic scheme and cyclization mechanism, consistent with the experimental data, is proposed.
