Stereospecific Electrophilic Fluorocyclization of α,β-Unsaturated Amides with Selectfluor
作者:Haiyang Fei、Zheyuan Xu、Hongmiao Wu、Lin Zhu、Hitesh B. Jalani、Guigen Li、Yao Fu、Hongjian Lu
DOI:10.1021/acs.orglett.0c00620
日期:2020.4.3
An efficient fluorocyclization of α,β-unsaturated amides through a formal halocyclization process is developed. The reaction proceeds undertransition-metal-freeconditions and leads to the formation of fluorinated oxazolidine-2,4-diones with excellent regio- and diastereoselectivity. The evaluation of the reaction mechanism based on preliminary experiments and density functional theory calculations
An unprecedented photocatalytic system consisting of benzimidazolium aryloxide betaines (BI+-ArO-) and stoichiometric hydride reducing reagents was developed for carrying out desulfonylation reactions of N-sulfonyl-indoles, -amides, and -amines, and α-sulfonyl ketones. Measurements of absorption spectra and cyclic voltammograms as well as density functional theory (DFT) calculations were carried out
Copper-catalyzeddecarboxylative thiolation using molecular oxygen as the sole oxidant was developed. A variety of aromaticcarboxylicacids including 2-nitrobenzoic acids, pentafluorobenzoic acid and several heteroaromatic carboxylicacids undergo efficient...
Photoinduced electrontransfer (PET) reactionspromoted by 2-aryl substituted 1,3-dimethylbenzimidazolines (Ar-DMBIH) were investigated. Excited states of Ar-DMBIH, formed by irradiation using light above 360 nm, initiatePETreductions of various organic substrates, including transformations of epoxy ketones to aldols, free radical rearrangements such as the Dowd-Beckwith ring-expansion and 5-exo
Palladium-Catalyzed Substitution and Cross-Coupling of Benzylic Fluorides
作者:George Blessley、Patrick Holden、Matthew Walker、John M. Brown、Véronique Gouverneur
DOI:10.1021/ol300977f
日期:2012.6.1
Benzylic fluorides are suitable substrates for Pd(0)-catalyzed Tsuji–Trost substitution using carbon, nitrogen, oxygen, and sulfur nucleophiles and for cross-coupling with phenylboronic acid. For the bifunctionalsubstrate 4-chlorobenzyl fluoride, fine-tuning of the reaction conditions allows for the regioselective displacement of either the chlorine or fluorine substituent. The leaving group ability
苯甲酸氟化物是使用碳,氮,氧和硫亲核试剂进行Pd(0)催化的Tsuji-Trost取代以及与苯基硼酸交叉偶联的合适底物。对于双官能底物4-氯苄基氟化物,反应条件的微调允许氯或氟取代基的区域选择性置换。的氟化物VS在替代移位其它基团的离去基团的能力是CF 3 CO 2 ≈ p -NO 2 ç 6 ħ 4 CO 2 ≈OCO 2 CH 3 >˚F> CH 3 CO 2,其排名与Pd催化下的烯丙基氟化物相似。