作者:Kui Zhang、Lingchao Cai、Zhongyue Yang、K. N. Houk、Ohyun Kwon
DOI:10.1039/c7sc04381c
日期:——
A novel bridged [2.2.1] bicyclic phosphineoxide, devised to circumvent the waste generation and burdens of purification that are typical of reactions driven by the generation of phosphineoxides, has been prepared in three steps from commercially available cyclopent-3-ene-1-carboxylic acid. The performance of this novel phosphineoxide was superior to those of current best-in-class counterparts, as
Rh<sup>III</sup>-Catalyzed [4 + 1] Annulations of 2-Hydroxy- and 2-Aminobenzaldehydes with Allenes: A Simple Method toward 3-Coumaranones and 3-Indolinones
method for the regio- and stereoselective synthesis of substituted 3-coumaranones from salicylaldehydes and allenes using a rhodium(III) catalyst has been developed. This procedure gives access to new 2-vinyl-substituted 3-coumaranone compounds. The method involves a RhIII-catalyzed aldehyde C–H activation and annulationreactions. Moreover, this RhIII-catalyzed [4 + 1] annulationreaction has been applied
1,2-Dihydroquinolines and a 1,2,3,4-tetrahydroquinoline were efficiently constructed using tandem Michael-aldol reaction starting from N-protected o-aminobenzaldehydes and α,β-unsaturated carbonyl compounds in good yield.
A highly enantioselective one-pot synthesis of cyclopropane-fused tetrahydroquinolines bearing carbonyl functionalities, which are difficult to synthesize using conventional methods, is reported. Employing readily accessible alkene-tethered anthranilaldehydes, hydrazone formation and subsequent Ru-catalyzed intramolecular cyclopropanation furnish the desired products in ≤87% yield and ≤95% ee under