Transition metal-free oxidation of ynamides for synthesis of α-keto-imides
摘要:
Transition metal-free double oxidation of triple bonds in ynamides for synthesis of alpha-keto-imides is described. The successful key was combination of NIS and DMSO under atmospheric air in CPME solvent, and the reaction quickly proceeds at 0 degrees C within 1 h. Although the yields and substrate generality are moderate, yet the prototype protocol avoids the use of expensive, moisture-sensitive, toxic, and explosive additives, which make it potentially and significantly greener than current alternatives. (C) 2014 Elsevier Ltd. All rights reserved.
Regio- and stereospecific synthesis of (E)-α-iodoenamide moieties from ynamides through iodotrimethylsilane-mediated hydroiodation
摘要:
A facile approach to (E)-alpha-haloenamide moieties from ynamides using bromo- or iodotrimethylsilane is described. The simple protocol enables a regio- and stereospecific hydrohalogenation of the triple bond in gram-scale and provides a general entry for synthesis of novel enamide analogues. (C) 2012 Elsevier Ltd. All rights reserved.
Regio-, and Stereoselective Iodobromination of Ynamides for Synthesis of (<i>E</i>)-1-Bromo-2-iodoenamides
作者:Masataka Ide、Yuta Yauchi、Tetsuo Iwasawa
DOI:10.1002/ejoc.201402057
日期:2014.5
One-step synthesis of vicinal bromoiodoenamides from ynamides through IBr addition is described. Two types of IBr were used: commercially available IBr, and in situ generated IBr. This simple protocol enables highly efficient regio- and stereoselective iodobromination of the triple bond on a gram scale in anti-mode, and provides a potentially diverse scaffold for preparation of tetrasubstituted olefins