catalyst for cyclopropanationreactions of diazoesters with various allylsilanes. Also, methyl(diazoacetoxy)acetate afforded in significantly enhanced yields, diastereoselectivities, and enantioselectivities. The cyclopropanationreactions with vinylsilanes with methyl (diazoacetoxy)acetate proceeded with excellent diastereoselectivities (>99 : 1 d.r.). Moreover, cyclopropylsilane derivatives could be successfully
In Situ Generation of Oxazole Ylide and Interception with Sulfonamide: Construction of Amidines Using Two Diazo Molecules
作者:Jijun Chen、Wenhao Long、Yanwei Zhao、Haiyan Li、Yonggao Zheng、Pengcheng Lian、Xiaobing Wan
DOI:10.1002/cjoc.201800208
日期:2018.9
A novel generation of oxazoleylide and interception with sulfonamide have been well developed to construct fully substituted amidines. This copper‐catalyzed four‐component reaction incorporates twodiazomolecules to target amidines and shows broad substrate scope, excellent functional groups tolerance and good to excellent yields.
Highly Stereoselective Cyclopropanation of α,β-Unsaturated Carbonyl Compounds with Methyl (Diazoacetoxy)acetate Catalyzed by a Chiral Ruthenium(II) Complex
Tantalizing triangles: The title reaction gives bicarbonyl cyclopropane products that can lead to versatile intermediates with high yields and stereoselectivities. This system was also applied to the enantioselective total synthesis of spiro cyclopropane oxindole, an HIV‐1 nonnucleoside reverse transcriptase inhibitor.