29600-47-3Relevant academic research and scientific papers
Ruthenium-Catalyzed Enantioselective Hydrogenation/Lactonization of 2-Acylarylcarboxylates: Direct Access to Chiral 3-Substituted Phthalides
Lu, Bin,Zhao, Mengmeng,Ding, Guangni,Xie, Xiaomin,Jiang, Lili,Ratovelomanana-Vidal, Virginie,Zhang, Zhaoguo
, p. 3989 - 3996 (2017/09/13)
Highly enantioselective tandem hydrogenation/lactonization of various 2-acylarylcarboxylates including 2-aroylarylcarboxylates were realized by using [RuCl(benzene)(S)-SunPhos]Cl as the catalyst under mild reaction conditions. Excellent enantioselectivities (up to 99.6 % ee) and activities (S/C=1000) were obtained. This convenient and practical method enables a direct access to a series of highly optically pure 3-substituted phthalides that are very important molecules as valuable pharmacological compounds and diversified synthons for medicinal chemistry. Moreover, a gram-scale reaction was performed to further demonstrate the practicality of this approach.
Reactions of Carbonyl Compounds in Basic Solutions. Part 9. Methoxide-catalysed Cyclization of Benzylidenephthalides and Methyl o-Phenylacetylbenzoates
Bowden, Keith,Chehel-Amiran, Mohsen
, p. 2031 - 2034 (2007/10/02)
The detailed mechanism of the methoxide-catalysed rearrangement of substituted benzylidenephthalides and both normal and pseudo methyl o-phenylacetylbenzoates to form 2-phenylindane-1,3-diones has been studied.A rate-acidity function correlation for the reactions in methanolic dimethyl sulphoxide (DMSO) shows a linear increase in rate with increasing H- to reach a maximum in rate before decreasing, except for the p-nitro substrate.This derivative shows a rate decrease throughout the H- range.The ρ values in methanol and in 94 mol percent methanolic DMSO are 1.7 and -1.6, respectively.The kinetic isotope effect has been observed with kH/kD 0.8-1.0.The equilibrium constants for ring-chain tautomerism of the methyl o-phenylacetylbenzoates have been determined and shown to be independent of substituent and solvent composition.The rate-determining step is the intramolecular attack of the anion of the normal ester on the ester carbonyl group.In methanol and methanolic DMSO of high methanol content this is preceded by the ionization equilibrium of the normal ester.In methanolic DMSO of low methanol content and for the p-nitro substrate, the initial state is the anion itself.
The Synthesis of 2-(5-Phenylthiazol-4-yl)benzoic Acids
Teitei, Tsutomu
, p. 605 - 611 (2007/10/02)
The four-step synthesis of 2-(5-phenylthiazol-4-yl)benzoic acid (2a), and its 2-amino derivatives (2b), required for testing as potential plant growth regulators, is described.The α-bromo ketone (9b) was conveniently prepared from commercially available 3
