178461-69-3Relevant articles and documents
Chiral ammonium hypoiodite salt-catalyzed enantioselective oxidative cycloetherification to 2-acyl tetrahydrofurans
Uyanik, Muhammet,Hayashi, Hiroki,Iwata, Hirokazu,Ishihara, Kazuaki
, p. 353 - 355 (2016)
2-Acyl tetrahydrofuran is a fundamental structure in natural products and pharmaceuticals. We achieved chiral quaternary ammonium hypoiodite salt-catalyzed enantioselective oxidative cycloetherification of δ-hydroxyketone derivatives. The corresponding 2-acyl tetrahydrofurans were obtained in high chemical yield with high enantioselectivity.
A scalable chemoenzymatic preparation of (R)-tetrahydrofuran-2-carboxylic acid
Fujima, Yoshito,Hirayama, Yoshihiro,Ikunaka, Masaya,Nishimoto, Yukifumi
, p. 1385 - 1391 (2007/10/03)
To develop a practical scalable approach to (R)-tetrahydrofuran-2-carboxylic acid (THFC) 1, a chiral building block for furopenem 2, enantioselective hydrolysis of its esters is explored: When ethyl (±)-tetrahydrofuran-2-carboxylate 3d (2 M, 288 g/L) is digested by an Aspergillus melleus protease {0.2% (w/v)} in a 1.5 M potassium phosphate buffer (pH 8) for 20 h, enantioselective hydrolysis proceeds with E=60 to give (R)-THFC 1 in 94.4% ee. On separation from the left-over antipodal ester (S)-3d by partition, (R)-THFC 1 is treated with N,N-dicyclohexylamine (DCHA) in methyl ethyl ketone/methanol (5:1) to precipitate the crystalline salt 4 that contains (R)-THFC 1 of >99% ee in 22% overall yield from (±)-3d.
