Chiral amine catalyzed enantio- and diastereoselective Michael reaction in brine
摘要:
Simple pyrrolidine-based chiral amines were synthesized and used for the Michael addition of different ketones to a variety of nitro-olefins in brine. The effect of different surfactants and acids on the yields and stereochemical outcome of the Michael adducts was studied in detail. Chiral amine 1g was found to catalyze the formation of Michael adducts with high enantioselectivity (up to >99%), diastereoselectivity [up to 98:2 (syn:anti)] and yield (up to 94%). (C) 2012 Elsevier Ltd. All rights reserved.
Chiral amine catalyzed enantio- and diastereoselective Michael reaction in brine
作者:Sarbjit Singh、Swapandeep Singh Chimni
DOI:10.1016/j.tetasy.2012.06.026
日期:2012.7
Simple pyrrolidine-based chiral amines were synthesized and used for the Michael addition of different ketones to a variety of nitro-olefins in brine. The effect of different surfactants and acids on the yields and stereochemical outcome of the Michael adducts was studied in detail. Chiral amine 1g was found to catalyze the formation of Michael adducts with high enantioselectivity (up to >99%), diastereoselectivity [up to 98:2 (syn:anti)] and yield (up to 94%). (C) 2012 Elsevier Ltd. All rights reserved.
Isoxazolylpyrrolidinylpiperazine Ligands, a New Class for Dopamine D<sub>3</sub>and D<sub>4</sub>Receptor Antagonists
作者:Yoo Na Oh、Jumyung Kwak、Hun Yeong Koh、Sun Ho Jung
DOI:10.5012/bkcs.2012.33.12.4227
日期:2012.12.20
ines and their binding affinities for dopamine D3 and D4 receptors. The synthesis of isoxazolylpyrrolidinylpiperazine derivatives is shown in Schemes 1, 2 and 3. The key synthetic strategy to these compounds involved couplingbetween two buildingblocks 2 and 3 using reductive amination reaction. Preparation of buildingblock 2 is described in Scheme 2. Protection of the amino group of pyrrolidin-2-ylmethanol