22362-60-3Relevant academic research and scientific papers
Nickel-Catalyzed Directed Cross-Electrophile Coupling of Phenolic Esters with Alkyl Bromides
Ding, Decai,Wang, chuan,Yang, feiyan
supporting information, p. 9203 - 9209 (2020/12/22)
Herein, we demonstrate the successful use of robust phenolic esters as an electrophilic acyl source in the reaction with diverse primary and secondary unactivated alkyl bromides. The cleavage of the relatively inert C-O bond is facilitated by the neighboring coordinating hydroxyl or sulfonamide moiety. By circumventing the use of pregenerated organometallics, this method allows efficient preparation of a variety of o-hydroxyl and tosyl-protected o-amino aryl ketones with high compatibility with a wide range of functionalities.
Rhodium-phosphoramidite catalyzed alkene hydroacylation: Mechanism and octaketide natural product synthesis
Von Delius, Max,Le, Christine M.,Dong, Vy M.
supporting information, p. 15022 - 15032 (2012/11/06)
We describe a method that allows salicylaldehyde derivatives to be coupled with a wide range of unactivated alkenes at catalyst loadings as low as 2 mol %. A chiral phosphoramidite ligand and the precise stoichiometry of heterogeneous base are key for high catalytic activity and linear regioselectivity. This protocol was applied in the atom- and step-economical synthesis of eight biologically active octaketide natural products, including anticancer drug candidate cytosporone B. Mechanistic studies provide insight on parameters affecting decarbonylation, a side reaction that limits the turnover number for catalytic hydroacylation. Deuterium labeling studies show that branched hydride insertion is fully reversible, whereas linear hydride insertion is largely irreversible and turnover-limiting. We propose that ligand (R a,R,R)-SIPHOS-PE effectively suppresses decarbonylation, and helps favor a turnover-limiting insertion, by lowering the barrier for reductive elimination in the linear-selective pathway. Together, these factors enable high reactivity and regioselectivity.
Nitrile-promoted Rh-catalyzed intermolecular hydroacylation of olefins with salicylaldehyde
Imai, Masanori,Tanaka, Masakazu,Nagumo, Shinji,Kawahara, Norio,Suemune, Hiroshi
, p. 2543 - 2546 (2008/02/02)
Rh-catalyzed intermolecular hydroacylation between salicylaldehyde and alkenylnitriles proceeded at room temperature to preferentially give normal-hydroacylated products. Addition of CH3CN and NaOAc accelerated the Rh-catalyzed hydroacylation of monoolefins to exclusively produce the normal-hydroacylated products under mild reaction conditions. Plausible mechanisms for the regioselections are also described.
Biodegradation of Nonionic Surfactants. I. Biotransformation of 4-(1-Nonyl)phenol by a Candida maltosa Isolate
Corti, A.,Frassinetti, S.,Vallini, G.,D'Antone, S.,Fichi, C.,Solaro, R.
, p. 83 - 88 (2007/10/03)
Results are reported concerning biodegradation of 4-(1-nonyl)phenol by cultures of a Candida maltosa strain isolated from aerobic sludge samples collected at a depuration plant treating wastewaters from a textile industry. The yeast was able to utilize 4-(1-nonyl)phenol as a sole carbon and energy source. Preliminary attempts to draw the actual metabolic pathway evidenced microbial attack on the alkyl chain with the production of 4-acetylphenol. To the best of our knowledge this is the first report describing a microorganism capable of attacking nonylphenol in axenic culture and at the same time allowing for the identification of its degradation products.
The Effect of Carbonyl Containing Groups in the Terminal Chains on Mesomorphic Properties in Aromatic Esters and Thioesters. I. α-Keto Groups on the Phenolic End
Neubert, Mary E.,Herlinger, Frank C.,Jirousek, Michael R.,Vries, Adriaan De
, p. 299 - 320 (2007/10/02)
The effect of inserting a ketone group in the α-position of the alkyl chain on the phenolic end of 4,4'-disubstituted phenylbenzoates and di-(4'-substituted phenyl)-trans-cyclohexane-1,4-dicarboxylates on mesomorphic properties as compared to those properties observed for the corresponding alkyl compounds was determined.Transition tempetatures were higher and mesophase ranges usually wider in the α-keto compounds in both series.Nematic phases were observed in both series, but a strong preference for a single smectic phase predominated with this being a smectic A phase in the phenylbenzoates and a smectic C phase in the cyclohexane diesters.A variety of crystal changes and a few complex melting transition were also observed in the cyclohexane diesters. - Keywords: liquid crystals; x-ray; phenylbenzoates; phase transistors; trans-cyclohexane-1,4-dicarboxylates.
