1092546-75-2Relevant academic research and scientific papers
Rh(III)-Catalyzed Annulation of 2-Biphenylboronic Acid with Diverse Activated Alkenes
Chang, Junbiao,Dong, Zhenzhen,Li, Xingwei,Liu, Bingxian,Yang, Lingyun
supporting information, p. 7199 - 7204 (2021/09/22)
Rhodium(III)-catalyzed annulation of 2-biphenylboronic acids with three classes of activated alkenes has been realized, leading to the synthesis of fused or bridged cyclic skeletons via transmetalation-initiated C-H activation. In the annulative coupling of 2-biphenylboronic acid with a CF3-substituted enone, the bulky cyclopentadienyl ligand (CptBu) in the catalyst proved effective to promote the reductive elimination process prior to protonolysis, affording the [4 + 2] annulated products instead of the simple 1,4-addition product. Seven-membered rings were obtained when disubstituted cyclopropenones were employed. Bridged cycles were isolated from the coupling of 2-biphenylboronic acid with benzoquinones as a result of 2-fold Michael additions. The substrate scopes were found to be broad with up to 99% yield under air-tolerant conditions.
Highly Enantioselective [3 + 2] Annulation of 3-Butynoates with β-Trifluoromethyl Enones Promoted by an Amine-Phosphine Binary Catalytic System
Ding, Kuiling,Han, Zhaobin,Lu, Yixin,Ni, Huanzhen,Wong, Yee Lin,Wu, Mingyue
supporting information, (2020/03/30)
We report a highly enantioselective [3 + 2] annulation between 3-butynoates and β-trifluoromethyl enones, furnishing trifluoromethylated cyclopentenes with three contiguous stereogenic centers in good yields, high diastereoselectivities, and excellent enantioselectivities. A unique catalytic system consisting of a simple amine and a chiral phosphine was devised, and the synergistic play of Lewis basic amine and phosphine was crucial for alkyne isomerization and subsequent cyclization. The protocol disclosed herein allows facile activation of 3-butynoates in phosphine-mediated asymmetric transformations.
Chiral Hydroxytetraphenylene-Catalyzed Asymmetric Conjugate Addition of Boronic Acids to Enones
Chai, Guo-Li,Sun, A-Qiang,Zhai, Dong,Wang, Juan,Deng, Wei-Qiao,Wong, Henry N.C.,Chang, Junbiao
supporting information, p. 5040 - 5045 (2019/07/03)
(S)-2,15-Br2-DHTP-catalyzed asymmetric conjugate addition of boronic acids to β-trifluoromethyl α,β-unsaturated ketones and enones was studied. The reaction afforded the corresponding Michael addition products in moderate to high yields with excellent enantioselectivities (up to 99:1 er). This catalytic system features mild reaction conditions, high efficiency, and tolerance to heteroarylboronic acids.
Rhodium(III)-catalyzed sp2 C-H bond addition to CF3-substituted unsaturated ketones
Jiang, Quanbin,Guo, Tenglong,Wu, Kaikai,Yu, Zhengkun
supporting information, p. 2913 - 2915 (2016/02/19)
Rhodium(iii)-catalyzed conjugate addition of aromatic and olefinic C-H bonds to CF3-substituted unsaturated ketones was efficiently achieved. Both arene and olefin substrates bearing a chelate assisted-directing group were coupled with a variet
