TMSOTf-mediated approach to 1,3-oxazin-2-one skeleton through one-pot successive reduction-[4 + 2] cyclization process of imides with ynamides
作者:Chen-Chen Zhang、Zhi-Peng Huo、Mei-Lin Tang、Yong-Xi Liang、Xun Sun
DOI:10.1016/j.tetlet.2021.152946
日期:2021.3
A one-pot approach to access functionalized 1,3-oxazin-2-one skeleton has been developed through successive reduction and subsequent [4 + 2] cyclization process of N-Boc lactams with ynamides by TMSOTf. As a result, a number of five to seven membered ring fused bicyclic [1,2-c][1], [3]oxazin-1-ones 12a-m and tricyclic derivatives 13a-f were obtained in moderate to excellent yields with excellent regioselectivities
Tertiary Enamide-Triggered S<sub>E</sub>Ar: Domino Allylation and Enamine-Type Addition
作者:Frédéric Beltran、Laurence Miesch
DOI:10.1021/acs.orglett.8b03987
日期:2019.3.15
ketospiro-enesulfonamides. By treatment with ZrCl4 and allylsilane, an intramolecular electrophilic aromatic substitution and subsequent allylation is observed. By treatment with TiCl4 and allylsilane, a double enamine-type reaction takes place, thus creating simultaneously four contiguous stereogenic centers diastereoselectively.
Nickel-Catalyzed Difunctionalization of Alkynyl Bromides with Thiosulfonates and N-Arylthio Succinimides: A Convenient Synthesis of 1,2-Thiosulfonylethenes and 1,1-Dithioethenes
cesium carbonate is described. An operationally simple and highly regioselective atom transfer radical addition (ATRA) of alkynyl bromides provides a wide range of (E)-1,2-thiosulfonylethenes (α-aryl-β-thioarylvinyl sulfones) in moderate to high yields. The extensive substrate scope of both alkynyl bromides and thiosulfonates is explored with a broad range of functional groups. Indole-derived 1,1-bromoalkenes
A general atom‐economical approach for the synthesis of α‐halomethyl ketones is demonstrated through Ce(SO4)2/acid co‐catalyzed hydration of a wide range of haloalkynes. The reactions are conducted under convenient conditions and provide products with excellent regioselectivity in good to excellent yields, with broad substrate scope. This protocol is an alternative to conventional α‐halogenation of