Protective group-free synthesis of new chiral diamines via direct azidation of 1,1-diaryl-2-aminoethanols
作者:Harendra Nath Roy、Arigala Pitchaiah、Miri Kim、In Taek Hwang、Kee-In Lee
DOI:10.1039/c3ra23205k
日期:——
A direct azidation of tertiary alcohols using sodium azide–sulfuric acid is described; the present method provides an efficient and practical path for the synthesis of new chiral diamines from unmasked 1,1-diaryl-2-aminoethanols derived from natural amino acids.
A novel sulfonamide catalyst based on a room temperature ionic liquid (RTIL) has been developed for the enantioselective reduction of ketones in refluxing toluene. The optically active secondary alcohol products were obtained in good enantiomeric excess and excellent yields. The imidazolium-tagged sulfonamide catalyst can be readily recovered and reused four times without any significant loss of catalytic activity. (c) 2006 Elsevier Ltd. All rights reserved.
Proton-exchanged montmorillonite-mediated reactions of methoxybenzyl esters and ethers
作者:Dongyin Chen、Chang Xu、Jie Deng、Chunhuan Jiang、Xiaoan Wen、Lingyi Kong、Ji Zhang、Hongbin Sun
DOI:10.1016/j.tet.2014.01.064
日期:2014.3
Lewis Acid-Mediated Rearrangement of Activated Cyclic Amines: A Facile Synthetic Protocol for the Preparation of Amino Carbonyl Compounds
作者:Sermadurai Selvakumar、Sivaraj Baktharaman、Vinod K. Singh
DOI:10.1021/jo702044k
日期:2007.12.1
Ring opening of activated cyclic amines to produce amino carbonyl compounds has been studied in the presence of Lewis acids. Whereas five- and six-membered rings cleave and rearrange via a 1,2-hydride shift, reaction in three- and four-membered rings takes place via a C−C bond migration. In the case of a three-membered ring, a wide variety of Lewis acids proved to be effective for the reaction. Base-induced