Cyclization and N-Iodosuccinimide-Induced Electrophilic Iodocyclization of 3-Aza-1,5-enynes To Synthesize 1,2-Dihydropyridines and 3-Iodo-1,2-dihydropyridines
摘要:
Metal-free cyclization and N-iodosuccinimide-induced electrophilic iodocyclization of readily available 3-aza-1,5-enynes have been developed. The reactions selectively give 1,2-dihydropyridines and 3-iodo-1,2-dihydropyridines involving an aza-Claisen rearrangement and a 6p-electrocyclization step. Furthermore, the reaction could be carried out in 10 g scale for the synthesis of 1,2-dihydropyridines.
Heteropoly Acid-catalyzed Direct Substitution of 2-Propynyl Alcohols with Sulfonamides
作者:J. S. Yadav、B. V. Subba Reddy、T. Srinivasa Rao、B. Bala. M. Krishna、G. G. K. S. Narayana Kumar
DOI:10.1246/cl.2007.1472
日期:2007.12.5
Directsubstitution of the hydroxygroup in 2-propynyl alcohols with sulfonamides has been achieved using 5 mol % of phosphomolybdic acid supported on silica gel (PMA/SiO2) under mild reaction cond...
A general and selective method for the direct amidation of secondary benzyl alcohols with both sulfonamides and carbamates is described. This method has been applied to a variety of substrates and the reaction proceeded smoothly at room temperature in the presence of 5 mol % molybdenum(V) chloride to give the desired products in good yields. (C) 2007 Elsevier Ltd. All rights reserved.
One-pot synthesis of pyridines from 3-aza-1,5-enynes
作者:Xiaoyi Xin、Dongping Wang、Xincheng Li、Boshun Wan
DOI:10.1016/j.tet.2013.10.038
日期:2013.12
Efficient one-pot transformation of 3-aza-1,5-enynes to poly-substituted pyridines in good to excellent yields has been developed. This reaction involved cyclization of 3-aza-enynes and elimination of sulfinyl acids steps. (C) 2013 Elsevier Ltd. All rights reserved.
Al(OTf)3: an efficient recyclable catalyst for direct nucleophilic substitution of the hydroxy group of propargylic alcohols with carbon- and heteroatom-centered nucleophiles to construct C–C, C–O, C–N and C–S bonds
A general and highly efficient Al(OTf)3-catalyzed methodology has been developed for the direct nucleophilic substitution of the hydroxygroup in propargylic alcohols with a variety of carbon- and heteroatom-centered nucleophiles such as alcohols, aromatic compounds, amides, and thiols, leading to the construction of C–C, C–O, C–N and C–S bonds.