Parallel synthesis of modular chiral Schiff base ligands and evaluation in the titatium(IV) catalyzed asymmetric trimethylsilylcyanation of aldehydes
摘要:
Highly modular tridentate Schiff base ligands arising from enantiopure epoxyalcohols have been prepared and evaluated in catalysis using parallel methods. The key structural motifs and experimental parameters have been identified, allowing enantioselectivities of up to 77% ee in the titatium-catalyzed trimetbylsilyl cyanide addition to aldehydes. (c) 2005 Elsevier Ltd. All rights reserved.
Synthesis of enantiopure amino alcohols by ring-opening of epoxyalcohols and epoxyethers with ammonia
摘要:
Arylglycidols and their corresponding ethers undergo regioselective ring-opening with aqueous ammonia in the presence of organic co-solvents (isopropanol or 1,4-dioxane) to afford 1,2-amino alcohols in high yield. (C) 2003 Elsevier Ltd. All rights reserved.