76116-13-7Relevant academic research and scientific papers
Palladium-Catalyzed Chemo- and Enantioselective C?O Bond Cleavage of α-Acyloxy Ketones by Hydrogenolysis
Chen, Jianzhong,Zhang, Zhenfeng,Liu, Delong,Zhang, Wanbin
supporting information, p. 8444 - 8447 (2016/07/19)
A chemoselective C?O bond cleavage of the ester alkyl side-chain of α-acyloxy ketones was realized for the first time by a highly efficient palladium-catalyzed hydrogenolysis (S/C=6000, the highest catalytic efficiency by far). Furthermore, a kinetic resolution of α-acyloxy ketones was first developed by enantioselective hydrogenolysis with good yields and up to 99 % ee.
Cyclization of alkynyl benzoates and generation of dioxolenylium ions
Allen, Annette D.,Kitamura, Tsugio,McClelland,Stang, Peter J.,Tidwell, Thomas T.
, p. 8873 - 8878 (2007/10/02)
Reactions of l-ethynyl benzoates RC≡CO2CC6H4X in H2O and CH3OH have been studied. In neutral H2O, reaction rates for CH3C≡CO2CC6H4X depend on σp of X with p of 1.3. Reaction of CH3C≡CO2CPh (1) in 18O-labeled H2O gives CH3CH2CO2H and PhCO2H in 54% relative yield with 90 and 83%, respectively, incorporation of a single 18O in the acids and CH3COCH2O2CPh (2) in 46% relative yield with 100% incorporation of 18O in both carbonyl oxygens. These results arc explained by the hypothesis that at least 46% of 1 reacts by cyclization to an intermediate 2-hydroxy-1,3-dioxolene 18. Mcthanolysis of 1 and other alkynyl benzoates gives 2-methoxy-1,3-dioxolenes, confirming the cyclization pathway. Reaction in 44% H2SO4 of 2-methoxy-2-phenyl-4-tert-butyl-1,3-dioxol-4-ene (8), prepared in this way, gives the 2-phenyl-4-tert-butyl-1,3-dioxol-4-enylium cation (16), directly observable by UV, which hydrolyzes to t-BuCOCH2O2CPh (12).
