Brønsted Acid Assisted Regio- and Enantioselective Direct O-Nitroso Aldol Reaction Catalysed by α,α-Diphenylprolinol Trimethylsilyl Ether
作者:Antonia Mielgo、Irene Velilla、Enrique Gómez-Bengoa、Claudio Palomo
DOI:10.1002/chem.201000376
日期:2010.7.5
p‐nitrobenzoic acid, the O‐nitroso aldol reaction of nitrosobenzene with enolisable aldehydes may be promoted by commercially available α,α‐diphenylprolinol trimethylsilyl ether. The reaction proceeds with good yields and essentially complete enantioselectivity, with catalyst loadings in the 5–10 mol % range. The resulting α‐oxyaldehyde adducts may be transformed in situ into α‐oxyimines, which provide 1,2‐amino
在对硝基苯甲酸的存在下,亚硝基苯与可缩醛的邻硝基亚硝基羟醛反应可通过市售的α,α-二苯基脯氨醇三甲基甲硅烷基醚来促进。该反应以良好的收率和基本完全的对映选择性进行,催化剂的负载量为5-10 mol%。生成的α-氧醛加合物可以原位转化为α-氧亚胺,用格氏试剂处理后可提供1,2-氨基醇,总收率良好(45-59%),典型的非对映异构体比率≥95:5。