5333-83-5Relevant articles and documents
A lewis acid site-activated reaction in zeolites: Thiophene acylation by butyryl chloride
Isaev,Fripiat
, p. 257 - 263 (1999)
The acylation of thiophene by butyryl chloride has been studied in the liquid phase in the presence of 12 catalysts: HZSM-5, H-mordenite, and HY (ultrastable Y) with various framework Si/Al ratios, various numbers of Bronsted and Lewis sites, and various amounts of nonframework aluminum. The numbers of Bronsted and Lewis acid sites were obtained by FT-IR using chemisorbed ammonia, as described elsewhere. There is a correlation between the initial rates of reaction and the number of Lewis acid sites, whereas there is no correlation between the initial rates and the number of Bronsted sites. The correlation with the number of Lewis sites may be considered significant, since it expands on more than one order of magnitude. Poisoning of the catalyst probably results from the oligomerization on butyryl chloride. No carboxylic acid has been detected in the course of the reaction. No attempt has been made to determine the nature of the poisoning reaction.
Rh-Catalyzed Coupling of Aldehydes with Allylboronates Enables Facile Access to Ketones
Zhang, Kezhuo,Huang, Jiaxin,Zhao, Wanxiang
supporting information, (2022/02/21)
We present herein a novel strategy for the preparation of ketones from aldehydes and allylic boronic esters. This reaction involves the allylation of aldehydes with allylic boronic esters and the Rh-catalyzed chain-walking of homoallylic alcohols. The key to this successful development is the protodeboronation of alkenyl borylether intermediate via a tetravalent borate anion species in the presence of KHF2 and MeOH. This approach features mild reaction conditions, broad substrate scope, and excellent functional group tolerance. Mechanistic studies also supported that the tandem allylation and chain-walking process were involved.
Selective Oxidation of Benzylic sp3C-H Bonds using Molecular Oxygen in a Continuous-Flow Microreactor
Ma, Cunfei,Meng, Qingwei,Tang, Xiaofei,Yu, Zongyi,Yun, Lei,Zhao, Jingnan
, p. 1612 - 1618 (2021/07/21)
Selective aerobic oxidation of benzylic sp3 C-H bonds to generate the corresponding ketones was achieved under continuous-flow conditions. The catalysts N-hydroxyphthalimide (NHPI) and tert-butyl nitrite (TBN) as the precursor of the radical under aerobic conditions motivated this process. Flow microreactors operating under optimized conditions enabled this oxidation with higher efficiency and a shortened reaction time of 54 s (total time was 10 min), which was improved 466 times compared with the batch parallel reaction (7.0 h). Notably, the catalyst and solvent recycling (92.6 and 94.5%) and scale-up experiments (0.87 g h-1 in 28 h) demonstrated the practicability of the protocol. The high product selectivity and functional group tolerance of the process allowed the production of ketones in yields of 41.2 to 90.3%. To reveal the versatility and applicability of this protocol, the late-stage modification of an antiepileptic drug to obtain oxcarbazepine was further conducted.
Iodine promoted α-hydroxylation of ketones
Siddaraju, Yogesh,Prabhu, Kandikere Ramaiah
supporting information, p. 6749 - 6753 (2015/06/25)
A novel method for α-hydroxylation of ketones using substoichiometric amount of iodine under metal-free conditions is described. This method has been successfully employed in synthesizing a variety of heterocyclic compounds, which are useful precursors. α-Hydroxylation of diketones and triketones are illustrated. This strategy provides a novel, efficient, mild and inexpensive method for α-hydroxylation of aryl ketones using a sub-stoichiometric amount of molecular iodine.
