Novel carbohydrate-based bifunctional organocatalysts for nucleophilic addition to nitroolefins and imines
作者:Alessandra Puglisi、Maurizio Benaglia、Laura Raimondi、Luigi Lay、Laura Poletti
DOI:10.1039/c0ob01240h
日期:——
cheap and readily available chiral scaffold for the synthesis of a series of novel enantiomerically pure bifunctional organocatalysts bearing a tertiary amino group in proximity to a (thio)urea group. The catalytic behaviour of these compounds, both as neutral and N-protonated species, was investigated using the addition of acetylacetone to β-nitrostyrene as a model reaction. Under optimized experimental
葡萄糖胺已被选择为便宜且容易获得的手性支架,用于合成一系列新颖的对映体纯的双官能的有机催化剂,其带有靠近(硫)脲基的叔氨基。研究了这些化合物作为中性和N质子化物质的催化行为,方法是加入乙酰丙酮 到 β-硝基苯乙烯作为模型反应。在优化的实验条件下,可获得高达93%的化学收率和高达89%的对映选择性。半经验(AM1)计算研究可以为所选催化剂的化学和立体化学行为找到理论依据。还对这些催化剂作为助催化剂进行了初步研究。丙二酸二乙酯的N -Boc亚胺苯甲醛,以高达81%ee的价格提供产品。