A hydroxy group chelation‐assisted stereospecific oxidative cross‐coupling reaction between alkenes was developed under mild reaction conditions. In the presence of palladium catalyst, the alkenes tethered with hydroxy functionality can couple efficiently with electron‐deficient alkenes to form the corresponding multi‐substituted olefin products. The hydroxy group on the substrate could play dual roles
Copper-Mediated Trifluoromethylation–Allylation of Arynes
作者:Xinkan Yang、Gavin Chit Tsui
DOI:10.1021/acs.orglett.8b00101
日期:2018.2.16
An unprecedented three-component copper-mediated vicinal trifluoromethylation–allylation of arynes is described. A wide range of structurally diverse trifluoromethylated allylarenes can be quickly assembled in one step. The application of the method has been demonstrated in the expedient synthesis of the CF3-containing analogue of the antispasmodic drug papaverine. The new reactivity of the [CuCF3]
Stereocontrolled Synthesis of Sulfonyl 2,5-Diaryltetrahydrofurans
作者:M.-Y. Chang、Y.-C. Cheng
DOI:10.1055/s-0035-1560423
日期:——
BF 3 ·OEt 2 -mediated stereocontrolled annulation of 4-alkenols affords sulfonyl 2,5-diaryltetrahydrofurans in good yields. The key synthetic route combines the facile stereoselective reduction of α-styryl-β-ketosulfones and an intramolecular Friedel–Crafts electrophilic cyclization of the resulting 4-alkenols. A plausible mechanism has been studied and proposed.
Solvent-Dependent Enantiodivergence in the Chlorocyclization of Unsaturated Carbamates
作者:Atefeh Garzan、Arvind Jaganathan、Nastaran Salehi Marzijarani、Roozbeh Yousefi、Daniel C. Whitehead、James E. Jackson、Babak Borhan
DOI:10.1002/chem.201300189
日期:2013.7.1
A remarkable solvent‐controlled enantiodivergence is seen in the hydroquinidine 1,4‐phthalazinediyl diether ((DHQD)2PHAL)‐catalyzed chlorocyclization of unsaturatedcarbamates. Eyring plot analyses of this previously unreported reaction are used to probe and compare the R‐ and S‐selective pathways. In the CHCl3/hexanes solvent system, the pro‐R process shows a surprising increase in selectivity with
In this work, we developed a concise synthetic route for the synthesis of polysubstituted naphthalenes starting from commercially available isovanillin and its derivatives. Reaction with styryl bromide via O-styrylation, Claisen rearrangement, enereaction, and O-alkylation occurred in high yields. The key structures were confirmed by single-crystal X-ray diffraction.