A variety of novel imidazolidinone-based organocatalysts with bulky substituents were synthesized under mild reaction conditions starting from easily accessible substrates. Different natural and unnatural amino acid methyl amides were cyclized with aromatic carbaldehydes to yield two diastereomeric MacMillan-type catalysts. Special emphasis was put on bulky residues such as mesityl and pyrene moieties.
使用易得的底物,在温和的反应条件下合成了一系列具有庞大取代基的新型咪唑烷酮基有机催化剂。不同的天然和非天然氨基酸甲酰胺与芳香醛缩合环化,生成两种二对映异构的MacMillan型催化剂。特别强调了像二甲苯基和芘基这样的庞大取代基。