Huguenot Florent, Billac Anne, Brigaud Thierry, Portella Charles
Institut de Chimie Moléculaire de Reims, CNRS - Université de Reims Champagne-Ardenne (UMR 6229), Faculté des Sciences, BP 1039, 51687 Reims Cedex 2, France.
J Org Chem. 2008 Apr 4;73(7):2564-9. doi: 10.1021/jo702328v. Epub 2008 Mar 11.
Difluoroenol silyl ethers, produced in situ from acylsilanes and CF3TMS, react as electrophiles with amines to give difluoroimines, via the corresponding hemiaminal adduct, as evidenced by 19F NMR spectroscopy. Reaction with (R)-phenylglycinol led to 2-difluoromethyloxazolidines. After separation of the diastereomers, reduction with LAH and Strecker-type synthesis gave enantiopure alpha-difluoromethylamines and alpha-difluoromethyl-alpha-amino acids, respectively.
由酰基硅烷和CF3TMS原位生成的二氟烯醇硅醚作为亲电试剂与胺反应,通过相应的半胺加合物生成二氟亚胺,19F NMR光谱证明了这一点。与(R)-苯基甘氨醇反应生成2-二氟甲基恶唑烷。分离非对映异构体后,用LAH还原并进行Strecker型合成,分别得到对映体纯的α-二氟甲基胺和α-二氟甲基-α-氨基酸。